JP3597178B2

JP3597178B2 - Wireless channel allocation control method, multiple system sharing system, and control device

Info

Publication number: JP3597178B2
Application number: JP2002152902A
Authority: JP
Inventors: 聖悟原野; 憲哉仲井間; 昭宏前原; 昌史増田
Original assignee: NTT Docomo Inc
Current assignee: NTT Docomo Inc
Priority date: 2002-05-27
Filing date: 2002-05-27
Publication date: 2004-12-02
Anticipated expiration: 2022-05-27
Also published as: JP2003348647A

Description

【０００１】
【発明の属する技術分野】
本発明は、複数方式共用システム、無線回線割り当て制御方法及び制御装置に係り、より詳しくは、複数の方式システムの各々に基づく通信を行うための無線回線の割り当て制御を行う各方式システム毎の制御装置と、複数の方式システムの各々に基づく通信を行うことが可能な共用移動局と、一の方式システムに基づく通信のみを行うことが可能な各方式システム毎の専用移動局とを含んで構成された複数方式共用システム、当該複数方式共用システムにて各制御装置が共用移動局に無線回線を割り当てる際の無線回線割り当て制御方法、及び当該複数方式共用システムを構成する制御装置に関する。
【０００２】
また、本発明は、１つの方式システムにおける複数の周波数帯域の各々について、当該周波数帯域で通信可能な移動局に対し無線回線を割り当てる無線回線の割り当て制御を行う各周波数帯域毎の制御装置と、複数の周波数帯域で通信可能な共用移動局と、１つの周波数帯域でのみ通信可能な各周波数帯域毎の専用移動局とを含んで構成された移動通信システムにて、各制御装置が前記共用移動局に無線回線を割り当てる際の無線回線割り当て制御方法に関する。更に、本発明は、制御装置について、各周波数帯域毎の制御装置でなく、複数の周波数帯域を制御対象とする制御装置が設けられている場合にも適用される。
【０００３】
【従来の技術】
複数の移動通信システム（本明細書では「方式システム」という）の代表的な例として、現在日本で商用サービスされているディジタル自動車電話方式（ＰｅｒｓｏｎａｌＤｉｇｉｔａｌＣｅｌｌｕｌａｒ：ＰＤＣ）における８００ＭＨｚ帯域システムと１５００ＭＨｚ帯域システムとがある。ＰＤＣの運用形態としては、８００ＭＨｚシステムと１５００ＭＨｚシステムとを別システムとして独立に運用する形態が一般的であったが、２つのシステムの各周波数帯を使用可能な移動局（以下「共用移動局」という）を導入した上で、それらの移動局を２つのシステムに振り分け、待ち受け中および通信開始時に２つのシステムに分散配置させることで、トラヒックや処理負荷を２つのシステムに分散させることにより、加入者容量の拡大を図ることを目的とした複数方式システムの共用方式が考えられている。
【０００４】
【発明が解決しようとする課題】
ところが、共用方式を実施した場合、各システムにおいて、専用移動局（８００ＭＨｚ帯域システムの周波数帯域のみを使用可能な移動局、または１５００ＭＨｚ帯域システムの周波数帯域のみを使用可能な移動局）と共用移動局とが混在することとなり、共用移動局が両システムヘの接続が可能であるのに対し、専用移動局は一つのシステムにのみ接続が制限されるため、各システムの容量および各システムに振り分けられた共用移動局の数によっては、共用移動局の回線使用によって、専用移動局が使用可能な回線が圧迫され、共用移動局の呼損率と比較して専用移動局の呼損率が著しく上昇するおそれがある。
【０００５】
本発明は、上記課題を解決するために成されたものであり、共用移動局の呼損率と比較して専用移動局の呼損率が上昇することを防止することができる複数方式共用システム、無線回線割り当て制御方法及び制御装置を提供することを目的とする。
【０００６】
【課題を解決するための手段】
【００１０】
上記目的を達成するために、本発明に係る無線回線割り当て制御方法は、複数の方式システムの各々に基づく通信を行うための無線回線の割り当て制御を行う各方式システム毎の制御装置と、複数の方式システムの各々に基づく通信を行うことが可能な共用移動局と、一の方式システムに基づく通信のみを行うことが可能な各方式システム毎の専用移動局とを含んで構成された複数方式共用システムにて、各制御装置が前記共用移動局に無線回線を割り当てる際の無線回線割り当て制御方法であって、各制御装置は、前記共用移動局への無線回線の割り当てを要求され且つ自装置が無線回線の割り当てを試みる最終候補の制御装置でない場合、所定条件に基づいて無線回線の割り当て可否を判定し、当該判定結果に基づいて無線回線の割り当てを制御し、前記共用移動局への無線回線の割り当てを要求され且つ自装置が無線回線の割り当てを試みる最終候補の制御装置である場合、無線回線の割り当て可否判定を回避し、前記共用移動局への無線回線の割り当てを行うことを特徴とする。
【００１１】
本発明に係る無線回線割り当て制御方法では、各制御装置は、共用移動局への無線回線の割り当てを要求され且つ自装置が無線回線の割り当てを試みる最終候補の制御装置でない場合に、所定条件に基づいて無線回線の割り当て可否を判定し、当該判定結果に基づいて無線回線の割り当てを制御する。このように、単に共用移動局への無線回線割り当て要求に応じて無条件に割り当てるのではなく、共用移動局への割り当て可否を判定した上で当該判定結果に基づいて無線回線の割り当てを制御することにより、共用移動機の回線使用によって、専用移動機が使用可能な回線が圧迫され、共用移動局の呼損率と比較して専用移動局の呼損率が上昇することを防止することができる。
【００１２】
その一方で、共用移動局への無線回線の割り当てを要求され且つ自装置が無線回線の割り当てを試みる最終候補の制御装置である場合には、無線回線の割り当て可否判定を回避し、共用移動局への無線回線の割り当てを行う。これにより、共用移動局についても著しい呼損率の上昇を防止することができ、専用移動局を使用するユーザおよび共用移動局を使用するユーザの双方に対し、可能な限り同等の接続品質を提供することができる。
【００１３】
なお、上記発明は、複数方式共用システムに係る発明、制御装置に係る発明としても記述することができる。即ち、本発明に係る複数方式共用システムは、複数の方式システムの各々に基づく通信を行うための無線回線の割り当て制御を行う各方式システム毎の制御装置と、複数の方式システムの各々に基づく通信を行うことが可能な共用移動局と、一の方式システムに基づく通信のみを行うことが可能な各方式システム毎の専用移動局とを含んで構成された複数方式共用システムであって、各制御装置が、前記共用移動局への無線回線の割り当て要求を当該共用移動局から受信する受信手段と、所定条件に基づいて無線回線の割り当て可否を判定する割り当て可否判定手段と、前記共用移動局への無線回線の割り当てを行う割り当て手段と、前記共用移動局への無線回線の割り当て要求を受信し且つ自装置が無線回線の割り当てを試みる最終候補の制御装置でない場合、前記割り当て可否判定手段により無線回線の割り当て可否を判定し、前記割り当て手段により当該判定結果に基づいて無線回線を割り当てるよう制御し、前記共用移動局への無線回線の割り当て要求を受信し且つ自装置が無線回線の割り当てを試みる最終候補の制御装置である場合、前記割り当て可否判定手段による無線回線の割り当て可否判定を回避し、前記割り当て手段により無線回線の割り当てを行うよう制御する制御手段とを備えたことを特徴とする。
【００１４】
また、本発明に係る制御装置は、複数の方式システムの各々に基づく通信を行うことが可能な共用移動局と、一の方式システムに基づく通信のみを行うことが可能な各方式システム毎の専用移動局とともに複数方式共用システムを構成し、複数の方式システムのうち所定の一の方式システムに基づく通信を行うための無線回線の割り当て制御を行う制御装置であって、前記共用移動局への無線回線の割り当て要求を当該共用移動局から受信する受信手段と、所定条件に基づいて無線回線の割り当て可否を判定する割り当て可否判定手段と、前記共用移動局への無線回線の割り当てを行う割り当て手段と、前記共用移動局への無線回線の割り当て要求を受信し且つ自装置が無線回線の割り当てを試みる最終候補の制御装置でない場合、前記割り当て可否判定手段により無線回線の割り当て可否を判定し、前記割り当て手段により当該判定結果に基づいて無線回線を割り当てるよう制御し、前記共用移動局への無線回線の割り当て要求を受信し且つ自装置が無線回線の割り当てを試みる最終候補の制御装置である場合、前記割り当て可否判定手段による無線回線の割り当て可否判定を回避し、前記割り当て手段により無線回線の割り当てを行うよう制御する制御手段とを備えたことを特徴とする。
【００１５】
ところで、ある制御装置が最終候補の制御装置であるか否かの判定は、当該制御装置（自装置）が行ってもよいし、共用移動局から割り当て要求を受信した制御装置（呼を受け付けた制御装置）が行ってもよいし、共用移動局が行ってもよい。これら３パターンについて、無線回線割り当て制御方法に係る発明及び複数方式共用システムに係る発明として、以下のように記述することができる。
【００１６】
ある制御装置が最終候補の制御装置であるか否かの判定を当該制御装置が行う態様は、以下のように記述できる。即ち、本発明に係る無線回線割り当て制御方法では、無線回線の割り当て要求には、前記共用移動局の通信可能な方式システム情報が含まれており、各制御装置は、当該共用移動局の通信可能な方式システム情報に基づいて、自装置が無線回線の割り当てを試みる最終候補の制御装置であるか否かを判定することを特徴とする。また、本発明に係る複数方式共用システムでは、無線回線の割り当て要求には、前記共用移動局の通信可能な方式システム情報が含まれており、各制御装置が、当該共用移動局の通信可能な方式システム情報に基づいて、自装置が無線回線の割り当てを試みる最終候補の制御装置であるか否かを判定する第１の最終候補判定手段をさらに備えたことを特徴とする。
【００１７】
ある制御装置が最終候補の制御装置であるか否かの判定を、共用移動局から割り当て要求を受信した制御装置が行う態様は、以下のように記述できる。即ち、本発明に係る無線回線割り当て制御方法では、共用移動局は、当該共用移動局の通信可能な方式システム情報を含む割り当て要求を出力し、前記割り当て要求を受信した一の制御装置は、所定条件に基づいて無線回線の割り当て可否を判定し、当該判定結果が割り当て不可の場合、前記共用移動局の通信可能な方式システム情報に基づいて、他の候補となる制御装置が無線回線の割り当てを試みる最終候補の制御装置であるか否かを判定し、当該最終候補の判定情報を前記割り当て要求に付加して、他の候補となる制御装置へ出力することを特徴とする。また、本発明に係る複数方式共用システムでは、共用移動局が、当該共用移動局の通信可能な方式システム情報を含む割り当て要求を出力し、前記制御装置が、前記割り当て可否判定手段により割り当て不可と判定された場合、前記共用移動局の通信可能な方式システム情報に基づいて、他の候補となる制御装置が無線回線の割り当てを試みる最終候補の制御装置であるか否かを判定する第２の最終候補判定手段と、当該最終候補の判定情報を前記割り当て要求に付加して、他の候補となる制御装置へ出力する要求出力手段と、をさらに備えたことを特徴とする。
【００１８】
ある制御装置が最終候補の制御装置であるか否かの判定を、共用移動局が行う態様は、以下のように記述できる。即ち、本発明に係る無線回線割り当て制御方法では、無線回線の割り当て要求を受信した一の制御装置は、所定条件に基づいて無線回線の割り当て可否を判定し、当該判定結果が割り当て不可の場合、当該判定結果を前記共用移動局へ通知し、当該共用移動局は、自局の通信可能な方式システム情報に基づいて、他の候補となる制御装置が無線回線の割り当てを試みる最終候補の制御装置であるか否かを判定し、当該最終候補の判定情報を前記割り当て要求に付加して、他の候補となる制御装置へ出力することを特徴とする。また、本発明に係る複数方式共用システムでは、前記制御装置が、前記割り当て可否判定手段により割り当て不可と判定された場合、当該判定結果を前記共用移動局へ通知する通知手段をさらに備え、前記共用移動局が、自局の通信可能な方式システム情報に基づいて、他の候補となる制御装置が無線回線の割り当てを試みる最終候補の制御装置であるか否かを判定する候補判定手段と、当該最終候補の判定情報を前記割り当て要求に付加して、他の候補となる制御装置へ出力する出力手段とをさらに備えたことを特徴とする。
【００１９】
ところで、各制御装置における無線回線の割り当て可否判定については、以下のような態様を採用することができる。
【００２０】
即ち、本発明では、各制御装置は、無線回線の割り当て可否の判定において、自装置の制御下の無線ゾーン内における全無線回線数に対する全移動局が使用中の無線回線数の割合を表す全移動局の回線使用率を、第１のしきい値と比較し、全移動局の回線使用率が第１のしきい値よりも低い場合に割り当て可能と判定し、全移動局の回線使用率が第１のしきい値以上の場合に割り当て不可と判定することを特徴とする。
【００２１】
また、本発明では、各制御装置は、無線回線の割り当て可否の判定において、自装置の制御下の無線ゾーン内における全無線回線数に対する共用移動局が使用中の無線回線数の割合を表す共用移動局の回線使用率を、第２のしきい値と比較し、共用移動局の回線使用率が第２のしきい値よりも低い場合に割り当て可能と判定し、共用移動局の回線使用率が第２のしきい値以上の場合に割り当て不可と判定することを特徴とする。
【００２２】
また、本発明では、各制御装置は、無線回線の割り当て可否の判定において、自装置の制御下の無線ゾーン内における全無線回線数に対する全移動局が使用中の無線回線数の割合を表す全移動局の回線使用率を第１のしきい値と比較するとともに、全無線回線数に対する共用移動局が使用中の無線回線数の割合を表す共用移動局の回線使用率を第２のしきい値と比較し、全移動局の回線使用率が第１のしきい値よりも低く且つ共用移動局の回線使用率が第２のしきい値よりも低い場合に割り当て可能と判定し、全移動局の回線使用率が第１のしきい値以上であるか又は共用移動局の回線使用率が第２のしきい値以上である場合に割り当て不可と判定することを特徴とする。
【００２３】
また、本発明では、各制御装置は、無線回線の割り当て可否の判定において、自装置の制御下の無線ゾーン内における全無線回線数に対する全移動局が使用中の無線回線数の割合を表す全移動局の回線使用率を第１のしきい値と比較するとともに、全無線回線数に対する共用移動局が使用中の無線回線数の割合を表す共用移動局の回線使用率を第２のしきい値と比較し、全移動局の回線使用率が第１のしきい値よりも低いか又は共用移動局の回線使用率が第２のしきい値よりも低い場合に割り当て可能と判定し、全移動局の回線使用率が第１のしきい値以上であり且つ共用移動局の回線使用率が第２のしきい値以上である場合に割り当て不可と判定することを特徴とする。
【００２４】
また、本発明では、各制御装置は、無線回線の割り当て可否の判定において、自装置の制御下の無線ゾーン内における一定時間内での専用移動局からの無線回線割り当て要求数に対する専用移動局への無線回線の割り当て失敗数の割合を表す専用移動局の呼損率を、第３のしきい値と比較し、専用移動局の呼損率が第３のしきい値よりも低い場合に割り当て可能と判定し、専用移動局の呼損率が第３のしきい値以上の場合に割り当て不可と判定することを特徴とする。
【００２５】
また、本発明では、各制御装置は、無線回線の割り当て可否の判定において、自装置の制御下の無線ゾーン内における一定時間内での専用移動局からの無線回線割り当て要求数に対する専用移動局への無線回線の割り当て失敗数の割合を表す専用移動局の呼損率を、前記無線ゾーン内における一定時間内での共用移動局からの無線回線割り当て要求数に対する共用移動局への無線回線の割り当て失敗数の割合を表す共用移動局の呼損率と比較し、専用移動局の呼損率が共用移動局の呼損率以下の場合に割り当て可能と判定し、専用移動局の呼損率が共用移動局の呼損率よりも高い場合に割り当て不可と判定することを特徴とする。
【００２６】
ところで、本発明は、前述した無線回線割り当て制御方法と同様の原理で、１つの方式システムにおける複数の周波数帯域の各々について、当該周波数帯域で通信可能な移動局に対し無線回線を割り当てる際にも、適用することができ、同様の作用・効果を得ることができる。
【００２７】
即ち、請求項１２に記載した無線回線割り当て制御方法は、１つの方式システムにおける複数の周波数帯域の各々について、当該周波数帯域で通信可能な移動局に対し無線回線を割り当てる無線回線の割り当て制御を行う制御装置と、複数の周波数帯域で通信可能な共用移動局と、１つの周波数帯域でのみ通信可能な各周波数帯域毎の専用移動局とを含んで構成された移動通信システムにて、前記制御装置が前記共用移動局に無線回線を割り当てる際の無線回線割り当て制御方法であって、前記制御装置は、前記共用移動局への無線回線の割り当てを要求された場合、所定条件に基づいて無線回線の割り当て可否を判定し、当該判定結果に基づいて無線回線の割り当てを制御することを特徴とする。
【００２８】
ここで、各周波数帯域毎に制御装置が存在する場合について、請求項１３のように記述することができる。即ち、請求項１３に記載した無線回線割り当て制御方法は、１つの方式システムにおける複数の周波数帯域の各々について、当該周波数帯域で通信可能な移動局に対し無線回線を割り当てる無線回線の割り当て制御を行う各周波数帯域毎の制御装置と、複数の周波数帯域で通信可能な共用移動局と、１つの周波数帯域でのみ通信可能な各周波数帯域毎の専用移動局とを含んで構成された移動通信システムにて、各制御装置が前記共用移動局に無線回線を割り当てる際の無線回線割り当て制御方法であって、各制御装置は、前記共用移動局への無線回線の割り当てを要求された場合、所定条件に基づいて無線回線の割り当て可否を判定し、当該判定結果に基づいて無線回線の割り当てを制御することを特徴とする。
【００２９】
即ち、本発明に係る無線回線割り当て制御方法は、１つの方式システムにおける複数の周波数帯域の各々について、当該周波数帯域で通信可能な移動局に対し無線回線を割り当てる無線回線の割り当て制御を行う各周波数帯域毎の制御装置と、複数の周波数帯域で通信可能な共用移動局と、１つの周波数帯域でのみ通信可能な各周波数帯域毎の専用移動局とを含んで構成された移動通信システムにて、各制御装置が前記共用移動局に無線回線を割り当てる際の無線回線割り当て制御方法であって、各制御装置は、前記共用移動局への無線回線の割り当てを要求され且つ自装置が無線回線の割り当てを試みる最終候補の制御装置でない場合、所定条件に基づいて無線回線の割り当て可否を判定し、当該判定結果に基づいて無線回線の割り当てを制御し、前記共用移動局への無線回線の割り当てを要求され且つ自装置が無線回線の割り当てを試みる最終候補の制御装置である場合、無線回線の割り当て可否判定を回避し、前記共用移動局への無線回線の割り当てを行うことを特徴とする。
【００３０】
また、本発明に係る無線回線割り当て制御方法では、無線回線の割り当て要求には、前記共用移動局の通信可能な周波数帯域情報が含まれており、各制御装置は、当該共用移動局の通信可能な周波数帯域情報に基づいて、自装置が無線回線の割り当てを試みる最終候補の制御装置であるか否かを判定することを特徴とする。
【００３１】
また、本発明に係る無線回線割り当て制御方法では、共用移動局は、当該共用移動局の通信可能な周波数帯域情報を含む割り当て要求を出力し、前記割り当て要求を受信した一の制御装置は、所定条件に基づいて無線回線の割り当て可否を判定し、当該判定結果が割り当て不可の場合、前記共用移動局の通信可能な周波数帯域情報に基づいて、他の候補となる制御装置が無線回線の割り当てを試みる最終候補の制御装置であるか否かを判定し、当該最終候補の判定情報を前記割り当て要求に付加して、他の候補となる制御装置へ出力することを特徴とする。
【００３２】
また、本発明に係る無線回線割り当て制御方法では、無線回線の割り当て要求を受信した一の制御装置は、所定条件に基づいて無線回線の割り当て可否を判定し、当該判定結果が割り当て不可の場合、当該判定結果を前記共用移動局へ通知し、当該共用移動局は、自局の通信可能な周波数帯域情報に基づいて、他の候補となる制御装置が無線回線の割り当てを試みる最終候補の制御装置であるか否かを判定し、当該最終候補の判定情報を前記割り当て要求に付加して、他の候補となる制御装置へ出力することを特徴とする。
【００３３】
ところで、各制御装置における無線回線の割り当て可否判定については、以下のような態様を採用することができる。
【００３４】
即ち、本発明では、前記制御装置は、無線回線の割り当て可否の判定において、自装置の制御対象の周波数帯域における全無線回線数に対する全移動局が使用中の無線回線数の割合を表す全移動局の回線使用率を、第１のしきい値と比較し、全移動局の回線使用率が第１のしきい値よりも低い場合に割り当て可能と判定し、全移動局の回線使用率が第１のしきい値以上の場合に割り当て不可と判定することを特徴とする。
【００３５】
また、本発明では、前記制御装置は、無線回線の割り当て可否の判定において、自装置の制御対象の周波数帯域における全無線回線数に対する共用移動局が使用中の無線回線数の割合を表す共用移動局の回線使用率を、第２のしきい値と比較し、共用移動局の回線使用率が第２のしきい値よりも低い場合に割り当て可能と判定し、共用移動局の回線使用率が第２のしきい値以上の場合に割り当て不可と判定することを特徴とする。
【００３６】
また、本発明では、前記制御装置は、無線回線の割り当て可否の判定において、自装置の制御対象の周波数帯域における全無線回線数に対する全移動局が使用中の無線回線数の割合を表す全移動局の回線使用率を、第１のしきい値と比較するとともに、全無線回線数に対する共用移動局が使用中の無線回線数の割合を表す共用移動局の回線使用率を、第２のしきい値と比較し、全移動局の回線使用率が第１のしきい値よりも低く且つ共用移動局の回線使用率が第２のしきい値よりも低い場合に割り当て可能と判定し、全移動局の回線使用率が第１のしきい値以上であるか又は共用移動局の回線使用率が第２のしきい値以上である場合に割り当て不可と判定することを特徴とする。
【００３７】
また、本発明では、前記制御装置は、無線回線の割り当て可否の判定において、自装置の制御対象の周波数帯域における全無線回線数に対する全移動局が使用中の無線回線数の割合を表す全移動局の回線使用率を、第１のしきい値と比較するとともに、全無線回線数に対する共用移動局が使用中の無線回線数の割合を表す共用移動局の回線使用率を、第２のしきい値と比較し、全移動局の回線使用率が第１のしきい値よりも低いか又は共用移動局の回線使用率が第２のしきい値よりも低い場合に割り当て可能と判定し、全移動局の回線使用率が第１のしきい値以上であり且つ共用移動局の回線使用率が第２のしきい値以上である場合に割り当て不可と判定することを特徴とする。
【００３８】
また、本発明では、前記制御装置は、無線回線の割り当て可否の判定において、自装置の制御対象の周波数帯域における一定時間内での専用移動局からの無線回線割り当て要求数に対する専用移動局への無線回線の割り当て失敗数の割合を表す専用移動局の呼損率を、第３のしきい値と比較し、専用移動局の呼損率が第３のしきい値よりも低い場合に割り当て可能と判定し、専用移動局の呼損率が第３のしきい値以上の場合に割り当て不可と判定することを特徴とする。
【００３９】
また、本発明では、前記制御装置は、無線回線の割り当て可否の判定において、自装置の制御対象の周波数帯域における一定時間内での専用移動局からの無線回線割り当て要求数に対する専用移動局への無線回線の割り当て失敗数の割合を表す専用移動局の呼損率を、前記無線ゾーン内における一定時間内での共用移動局からの無線回線割り当て要求数に対する共用移動局への無線回線の割り当て失敗数の割合を表す共用移動局の呼損率と比較し、専用移動局の呼損率が共用移動局の呼損率以下の場合に割り当て可能と判定し、専用移動局の呼損率が共用移動局の呼損率よりも高い場合に割り当て不可と判定することを特徴とする。
【００４０】
上記のように本発明は、複数の方式システムの各々に基づく通信を行うための移動局への無線回線の割り当て制御のみならず、１つの方式システムにおける複数の周波数帯域の各々について、当該周波数帯域で通信可能な移動局に対し無線回線を割り当てる際にも、適用することができる。
【００４１】
また、本発明は、各方式システムへの無線回線割り当て可否の判定に限定されず、各方式システムにおける複数の周波数帯域の各々について、当該周波数帯域で通信可能な移動局に対し無線回線を割り当てる際の割り当て可否の判定にも適用することができる。このように本発明は、汎用性が非常に高く有効な技術といえる。
【００４２】
【発明の実施の形態】
以下、図面を参照しながら、本発明に係る実施の形態について説明する。
【００４３】
［本実施形態の構成例］
図１には、本実施形態における複数方式共用システム１００の構成図を示す。この図１に示すように、複数方式共用システム１００には２つの方式システム（システムＡ、Ｂ）が共存している。システムＡについては、当該システムＡを制御する無線回線制御局１０２がコアネットワーク１０１に接続され、無線基地局１０３が無線回線制御局１０２に接続されている。無線基地局１０３によって形成される無線ゾーン１０４内には、システムＡでのみ通信可能な専用移動局１０５と、システムＡ、Ｂの各々で通信可能な共用移動局１０６とが存在している。システムＢについては、当該システムＢを制御する無線回線制御局１０７がコアネットワーク１０１に接続され、無線基地局１０８が無線回線制御局１０７に接続されている。無線基地局１０８によって形成される無線ゾーン１０９内には、システムＢでのみ通信可能な専用移動局１１０と、システムＡ、Ｂの各々で通信可能な共用移動局１０６とが存在している。なお、無線回線制御局１０２、１０７が、本発明に係る制御装置に相当する。
【００４４】
図２には、無線回線制御局１０２の構成図を示す。この図２に示すように、無線回線制御局１０２は、コアネットワーク１０１との信号の送受信を行うためにコアネットワーク１０１に接続された送受信部２０１と、無線基地局１０３、専用移動局１０５及び共用移動局１０６との信号の送受信を行うために無線基地局１０３に接続された送受信部２０２と、無線回線使用率に関するしきい値や呼損率に関するしきい値を含む多数の情報を記憶した情報記憶部２０４と、これらの各構成部の動作を制御及び監視する制御部２０３とを含んで構成されている。制御部２０３は、例えば、無線回線の管理、無線回線割り当ての要求回数、無線回線割り当ての成功回数および失敗回数のカウント等を行い、それらの情報を情報記憶部２０４に格納するとともに、後述の無線回線の割り当て制御等を行う。なお、無線回線制御局１０７の構成も図２と同様である。
【００４５】
［無線回線割り当て処理の一例］
以下、本実施形態における無線回線割り当てに関する処理を説明する。図３には、システムＡにて待ち受け中の共用移動局１０６が無線回線の割り当てを要求してから、割り当てられる無線回線が決定するまでの流れを示す。
【００４６】
この図３に示すように、まず、共用移動局１０６は、システムＡの無線回線制御局１０２に対して、無線基地局１０３を介して無線回線割り当ての要求信号を送信する（Ｓ０１）。無線回線制御局１０２は、共用移動局１０６から無線回線割り当ての要求信号を受信すると、まず自局（無線回線制御局１０２自身）が共用移動局１０６により通信可能なシステムのうちの最終候補システムであるか否かを判定する（Ｓ０２）。このとき無線回線制御局１０２は、例えば、無線回線割り当ての要求信号に含まれた共用移動局１０６の通信可能なシステム情報を参照し、当該要求信号が他の無線回線制御局からの転送でなく共用移動局１０６から直接受信したという事実より、システムＡ以外にシステムＢが候補システムとして残っていると判断し、自局は最終候補システムでないと判定する。
【００４７】
自局は最終候補システムでないと判定した場合、共用移動局１０６への無線回線の割り当て可否を判定する（Ｓ０３）。この割り当て可否判定処理としては、後述する図４〜図９のさまざまな処理を採用することができる。処理内容は後述する。
【００４８】
Ｓ０３の割り当て可否判定処理において無線回線の割り当て可能と判定された場合（Ｓ０４で肯定判定の場合）、割り当てるべき回線の選択を試み、空き回線が存在するか否かを確認し（Ｓ０６）、空き回線が存在する場合は、選択された空き回線を共用移動局１０６に割り当てる処理を行う（Ｓ０８）。なお、Ｓ０２で自局が最終候補システムの場合は、割り当て可否判定処理（Ｓ０３）を回避する流れを採用する。この利点は後述する。
【００４９】
一方、Ｓ０３の割り当て可否判定処理において無線回線の割り当て不可と判定された場合（Ｓ０４で否定判定の場合）又はＳ０６で空き回線が存在しない場合は、システムＡの回線を共用移動局１０６に割り当てることは不可能と判断できるため、他の候補システム（システムＢ）の回線の割り当てを行うべく、無線回線制御局１０２は、コアネットワーク１０１を介してシステムＢの無線回線制御局１０７に対して当該共用移動局１０６への無線回線割り当ての要求信号を送信する（Ｓ０５、Ｓ０７）。
【００５０】
なお、システムＡ以外に候補システムが存在しない場合は、図示を省略したが、割り当て可否判定処理（Ｓ０３）を回避して、割り当てるべき回線の選択を試み、空き回線が存在するか否かを確認する（Ｓ０６）。空き回線が存在する場合は、選択された空き回線を共用移動局１０６に割り当てる処理を行い（Ｓ０８）、空き回線が存在しない場合は、共用移動局１０６に無線回線割り当てができない旨を通知して（Ｓ１６に相当）、図３の処理を終了する。
【００５１】
無線回線制御局１０７は、無線回線制御局１０２から無線回線割り当ての要求信号を受信すると、まず自局（無線回線制御局１０７自身）が共用移動局１０６により通信可能なシステムのうちの最終候補システムであるか否かを判定する（Ｓ０９）。このとき無線回線制御局１０７は、例えば、無線回線割り当ての要求信号に含まれた共用移動局１０６の通信可能なシステム情報（ここではシステムＡ、Ｂ）を参照し、当該要求信号がシステムＡの無線回線制御局１０２から受信したという事実より、自局のシステムＢ以外に候補システムは残っていないと判断できるため、自局は最終候補システムであると判定する。なお、共用移動局１０６の通信可能なシステム情報については、無線回線制御局１０２が、Ｓ０５又はＳ０７で無線回線制御局１０７に無線回線割り当ての要求信号を送信する前にシステムＡの情報を削除し、システムＢの情報のみを残すよう動作させてもよい。
【００５２】
Ｓ０９で自局は最終候補システムであると判定した場合、割り当て可否判定処理（Ｓ１０）を回避して、割り当てるべき回線の選択を試み、空き回線が存在するか否かを確認し（Ｓ１２）、空き回線が存在する場合は、空き回線が存在する旨の応答を無線回線制御局１０２に送信し（Ｓ１３）、無線回線制御局１０２が、選択された空き回線を共用移動局１０６に割り当てる処理を行う（Ｓ１４）。一方、Ｓ１２で空き回線が存在しない場合、システムＢの回線を共用移動局１０６に割り当てることは不可能と判断できるため、無線回線制御局１０７は、空き回線が存在しない旨の応答を無線回線制御局１０２に送信する（Ｓ１５）。この応答を受けた無線回線制御局１０２は、共用移動局１０６に無線回線割り当てができない旨を通知して（Ｓ１６）、図３の処理を終了する。
【００５３】
一方、Ｓ０９でシステムＢが最終候補システムでなく他の候補システム（例えばシステムＣ）が存在する場合、上述した無線回線制御局１０２での処理と同様に、無線回線の割り当て可否判定処理を行う（Ｓ１０）。判定処理の結果、割り当て可能と判定された場合（Ｓ１１で肯定判定の場合）、割り当てるべき回線の選択を試み、空き回線が存在するか否かを確認し（Ｓ１２）、空き回線が存在する場合は、空き回線が存在する旨の応答を無線回線制御局１０２に送信し（Ｓ１３）、無線回線制御局１０２が、選択された空き回線を共用移動局１０６に割り当てる処理を行う（Ｓ１４）。ただし、Ｓ１０の判定処理の結果、割り当て不可能と判定された場合（Ｓ１１で否定判定の場合）又はＳ１２で空き回線が存在しない場合は、システムＢの回線を共用移動局１０６に割り当てることは不可能と判断できるため、無線回線制御局１０７は、システムＣの回線の割り当てを行うべく、コアネットワーク１０１を介してシステムＣの無線回線制御局に対して共用移動局１０６への無線回線割り当ての要求信号を送信する。
【００５４】
そして、最終的に、割り当て可能な回線が有った時点で、そのシステムの無線回線制御局がシステムＡの無線回線制御局１０２へ通知して（Ｓ１３に相当）、当該無線回線制御局１０２が回線を割り当てる（Ｓ１４に相当）。一方、最終的に、割り当て可能な回線が無かった場合は、最後のシステムがシステムＡの無線回線制御局１０２に空き回線無しを通知し（Ｓ１５に相当）、当該無線回線制御局１０２が共用移動局１０６に回線割り当てができない旨を通知して（Ｓ１６に相当）、図３の処理を終了する。
【００５５】
以上のような図３の処理により、共用移動局１０６からの無線回線割り当て要求に基づき各システムに対して順番に、空き回線が探索され共用移動局１０６に割り当てられることとなる。
【００５６】
［割り当て可否判定処理に関する各種の実施態様］
ところで、本発明は、空き回線を単に共用移動局１０６に割り当てるのではなく、Ｓ０３、Ｓ１０で、後述の割り当て可否判定処理を行い、その判定結果に基づいて共用移動局１０６への割り当てを制御することを特徴とする。以下、図４〜図９を用いて割り当て可否判定処理のさまざまな態様を説明する。
【００５７】
図４の処理例では、全移動局の回線使用率を所定の第１のしきい値と比較し、全移動局の回線使用率が当該第１のしきい値よりも低いか否かを判定する（Ｓ４１）。ここで、全移動局の回線使用率とは、無線ゾーン内における全無線回線数に対する全移動局で使用中の回線数の割合である。そして、Ｓ４１で全移動局の回線使用率が第１のしきい値よりも低い場合は、無線回線の割り当て可能と判定し（Ｓ４２）、全移動局の回線使用率が第１のしきい値以上の場合は、無線回線の割り当て不可と判定する（Ｓ４３）。このような判定処理を行うことにより、共用移動局１０６に対して相対的に専用移動局１０５等が無線回線を確保する確率が高まり、専用移動局１０５等の呼損率の上昇を防止することができる。
【００５８】
図５の処理例では、共用移動局の回線使用率を所定の第２のしきい値と比較し、共用移動局の回線使用率が当該第２のしきい値よりも低いか否かを判定する（Ｓ５１）。ここで、共用移動局の回線使用率とは、無線ゾーン内における全無線回線数に対する、共用移動局が使用中の回線数の割合である。そして、Ｓ５１で共用移動局の回線使用率が第２のしきい値よりも低い場合は、無線回線の割り当て可能と判定し（Ｓ５２）、共用移動局の回線使用率が第２のしきい値以上の場合は、無線回線の割り当て不可と判定する（Ｓ５３）。このような判定処理を行うことにより、共用移動局１０６に対して相対的に専用移動局１０５等が無線回線を確保する確率が高まり、専用移動局１０５等の呼損率の上昇を防止することができる。
【００５９】
図６の処理例では、まず全移動局の回線使用率を所定の第１のしきい値と比較し、全移動局の回線使用率が当該第１のしきい値よりも低いか否かを判定する（Ｓ６１）。ここで、全移動局の回線使用率とは、無線ゾーン内における全無線回線数に対する全移動局で使用中の回線数の割合である。Ｓ６１で全移動局の回線使用率が第１のしきい値よりも低い場合は、Ｓ６２へ進み、共用移動局の回線使用率を所定の第２のしきい値と比較し、共用移動局の回線使用率が当該第２のしきい値よりも低いか否かを判定する。ここで、共用移動局の回線使用率とは、無線ゾーン内における全無線回線数に対する、共用移動局が使用中の回線数の割合である。Ｓ６２で共用移動局の回線使用率が第２のしきい値よりも低い場合は、無線回線の割り当て可能と判定する（Ｓ６３）。
【００６０】
一方、Ｓ６１で全移動局の回線使用率が第１のしきい値以上の場合、又はＳ６２で共用移動局の回線使用率が第２のしきい値以上の場合は、無線回線の割り当て不可と判定する（Ｓ６４）。このような判定処理を行うことにより、全移動局の回線使用率が第１のしきい値よりも低く且つ共用移動局の回線使用率が第２のしきい値よりも低い場合に、無線回線の割り当て可能と判定され、全移動局の回線使用率が第１のしきい値以上の場合又は共用移動局の回線使用率が第２のしきい値以上の場合に、無線回線の割り当て不可と判定されることとなり、共用移動局１０６に対して相対的に専用移動局１０５等が無線回線を確保する確率が高まり、専用移動局１０５等の呼損率の上昇を防止することができる。
【００６１】
図７の処理例では、まず全移動局の回線使用率を所定の第１のしきい値と比較し、全移動局の回線使用率が当該第１のしきい値よりも低いか否かを判定する（Ｓ７１）。ここで、全移動局の回線使用率とは、無線ゾーン内における全無線回線数に対する全移動局で使用中の回線数の割合である。Ｓ７１で全移動局の回線使用率が第１のしきい値よりも低い場合は、Ｓ７３へ進み、無線回線の割り当て可能と判定する。一方、Ｓ７１で全移動局の回線使用率が第１のしきい値以上の場合は、Ｓ７２へ進み、共用移動局の回線使用率を所定の第２のしきい値と比較し、共用移動局の回線使用率が当該第２のしきい値よりも低いか否かを判定する。ここで、共用移動局の回線使用率とは、無線ゾーン内における全無線回線数に対する、共用移動局が使用中の回線数の割合である。Ｓ７２で、共用移動局の回線使用率が第２のしきい値よりも低い場合は、無線回線の割り当て可能と判定する（Ｓ７３）。
【００６２】
また、Ｓ７２で共用移動局の回線使用率が第２のしきい値以上の場合は、無線回線の割り当て不可と判定する（Ｓ７４）。このような判定処理を行うことにより、全移動局の回線使用率が第１のしきい値よりも低いか又は共用移動局の回線使用率が第２のしきい値よりも低い場合に、無線回線の割り当て可能と判定され、全移動局の回線使用率が第１のしきい値以上であり且つ共用移動局の回線使用率が第２のしきい値以上の場合に、無線回線の割り当て不可と判定されることとなり、共用移動局１０６に対して相対的に専用移動局１０５等が無線回線を確保する確率が高まり、専用移動局１０５等の呼損率の上昇を防止することができる。
【００６３】
図８の処理例では、専用移動局の呼損率を所定の第３のしきい値と比較し、専用移動局の呼損率が当該第３のしきい値よりも低いか否かを判定する（Ｓ８１）。ここで、専用移動局の呼損率とは、無線ゾーン内における一定時間内での専用移動局からの無線回線の割り当て要求数に対する専用移動局への無線回線割り当ての失敗回数の割合である。そして、Ｓ８１で専用移動局の呼損率が第３のしきい値よりも低い場合は、無線回線の割り当て可能と判定し（Ｓ８２）、専用移動局の呼損率が第３のしきい値以上の場合は、無線回線の割り当て不可と判定する（Ｓ８３）。このような判定処理を行うことにより、専用移動局の呼損率が許容された一定値以下に収まるようになり、専用移動局の呼損率上昇を防止することができる。
【００６４】
図９の処理例では、専用移動局の呼損率と共用移動局の呼損率とを比較し、専用移動局の呼損率が共用移動局の呼損率以下であるか否かを判定する（Ｓ９１）。ここで、専用移動局の呼損率とは、無線ゾーン内における一定時間内での専用移動局からの無線回線の割り当て要求数に対する専用移動局への無線回線割り当ての失敗回数の割合であり、共用移動局の呼損率とは、無線ゾーン内における一定時間内での共用移動局からの無線回線の割り当て要求数に対する共用移動局への無線回線割り当ての失敗回数の割合である。Ｓ９１で専用移動局の呼損率が共用移動局の呼損率以下である場合に無線回線の割り当て可能と判定し（Ｓ９２）、専用移動局の呼損率が共用移動局の呼損率よりも高い場合に無線回線の割り当て不可と判定する（Ｓ９３）。このような判定処理を行うことにより、専用移動局の呼損率が共用移動局の呼損率以下となり、専用移動局と共用移動局の接続品質を可能な限り同等に保つことができる。
【００６５】
以上のような図３の無線回線割り当て処理及び図４〜図９の判定処理により、無線ゾーン内における回線使用率または呼損率に応じて、共用移動局に対する回線割り当ての可否を決定するため、共用移動機の回線使用により専用移動機が使用可能である回線が圧迫され、共用移動局の呼損率と比較して専用移動局の呼損率が上昇することを防止することができる。
【００６６】
また、共用移動局への無線回線割り当てを試みる最終候補システム（図３でのシステムＢ）においては、割り当て可否判定処理（図３のＳ１０）を回避して専用移動局と同様に空き無線回線を割り当てるため、共用移動局についても著しい呼損率の上昇を防止することができ、専用移動局を使用するユーザ、および共用移動局を使用するユーザに対し、可能な限り同等の接続品質を提供することができる。
【００６７】
［無線回線割り当て処理に関する別の実施態様］
ところで、図３の無線回線割り当て処理については、図１０、図１１のような別の処理態様を採用することができる。以下、これらの処理を図面に沿って説明する。
【００６８】
図１０の処理例は、最初に共用移動局１０６から要求を受けた無線回線制御局１０２が無線回線の割り当てをとりまとめる態様である。即ち、無線回線制御局１０２が自局での無線回線の割り当て不可と判定し他のシステム（システムＢ）の無線回線制御局１０７に無線回線割り当て要求を送信するに際し、事前に当該相手方（システムＢ）が最終候補システムか否かを判定し、最終候補システムの場合には、システムＢが最終候補システムであることを告知する情報（最終候補情報）を無線回線割り当て要求に付加して送信する態様である。
【００６９】
即ち、図１０に示すように、まず、共用移動局１０６は、システムＡの無線回線制御局１０２に対して、無線基地局１０３を介して無線回線割り当ての要求信号を送信する（Ｓ２１）。無線回線制御局１０２は、共用移動局１０６から無線回線割り当ての要求信号を受信する。ここで図示は省略したが、無線回線制御局１０２は、まず自局（無線回線制御局１０２自身）が共用移動局１０６により通信可能なシステムのうちの最終候補システムであるか否かを判定する。このとき例えば、無線回線割り当ての要求信号に含まれた共用移動局１０６の通信可能なシステム情報を参照し、当該要求信号が他の無線回線制御局からの転送でなく共用移動局１０６から直接受信したという事実より、システムＡ以外にシステムＢが候補システムとして残っていると判断し、自局は最終候補システムでないと判定することができる。
【００７０】
そして、無線回線制御局１０２は、前述のような割り当て可否判定処理を行う（Ｓ２２）。この割り当て可否判定処理において無線回線の割り当て可能と判定された場合（Ｓ２３で肯定判定の場合）、割り当てるべき回線の選択を試み、空き回線が存在するか否かを確認し（Ｓ２４）、空き回線が存在する場合は、選択された空き回線を共用移動局１０６に割り当てる処理を行う（Ｓ２５）。
【００７１】
一方、Ｓ２２の割り当て可否判定処理において無線回線の割り当て不可と判定された場合（Ｓ２３で否定判定の場合）又はＳ２４で空き回線が存在しない場合は、システムＡの回線を共用移動局１０６に割り当てることは不可能と判断できるため、他の候補システム（システムＢ）の回線の割り当てを行うべく、無線回線制御局１０２は、システムＢが共用移動局１０６により通信可能なシステムのうちの最終候補システムであるか否かを判定する（Ｓ２６）。このとき無線回線制御局１０２は、例えば、無線回線割り当ての要求信号に含まれた共用移動局１０６の通信可能なシステム情報（システムＡとＢ）を参照することで、システムＢが最終候補システムであると判断し、送信相手のシステムＢが最終候補システムであることを告知する情報（最終候補情報）を無線回線割り当て要求に付加して（Ｓ２７）、コアネットワーク１０１を介してシステムＢの無線回線制御局１０７へ割り当て要求信号を送信する（Ｓ２８）。
【００７２】
なお、システムＡ以外に候補システムが存在しない場合は、図示を省略したが、割り当て可否判定処理（Ｓ２２）を回避して、割り当てるべき回線の選択を試み、空き回線が存在するか否かを確認する（Ｓ２４）。空き回線が存在する場合は、選択された空き回線を共用移動局１０６に割り当てる処理を行い（Ｓ２５）、空き回線が存在しない場合は、共用移動局１０６に無線回線割り当てができない旨を通知して（Ｓ３６に相当）、図１０の処理を終了する。
【００７３】
さて、無線回線制御局１０７は、無線回線制御局１０２から割り当て要求信号を受信すると、まず自局（無線回線制御局１０７自身）が最終候補システムであるか否かを、要求信号に最終候補情報が付加されているか否かによって判定する（Ｓ２９）。このとき無線回線制御局１０７は、上記の最終候補情報が割り当て要求信号に含まれているため、当該最終候補情報によって自局は最終候補システムであることを認識する。
【００７４】
Ｓ２９で自局は最終候補システムであると判定した場合、割り当て可否判定処理（Ｓ３０）を回避して、割り当てるべき回線の選択を試み、空き回線が存在するか否かを確認し（Ｓ３２）、空き回線が存在する場合は、空き回線が存在する旨の応答を無線回線制御局１０２に送信し（Ｓ３３）、無線回線制御局１０２が、選択された空き回線を共用移動局１０６に割り当てる処理を行う（Ｓ３４）。一方、Ｓ３２で空き回線が存在しない場合、システムＢの回線を共用移動局１０６に割り当てることは不可能と判断できるため、無線回線制御局１０７は、空き回線が存在しない旨の応答を無線回線制御局１０２に送信する（Ｓ３５）。この応答を受けた無線回線制御局１０２は、無線回線を割り当てる候補システムが尽きたため、共用移動局１０６に無線回線割り当てができない旨を通知して（Ｓ３６）、図１０の処理を終了する。
【００７５】
一方、Ｓ２９でシステムＢが最終候補システムでなく他の候補システム（例えばシステムＣ）が存在する場合、上述した無線回線制御局１０２での処理と同様に、無線回線の割り当て可否判定処理を行う（Ｓ３０）。判定処理の結果、割り当て可能と判定された場合（Ｓ３１で肯定判定の場合）、割り当てるべき回線の選択を試み、空き回線が存在するか否かを確認し（Ｓ３２）、空き回線が存在する場合は、空き回線が存在する旨の応答を無線回線制御局１０２に送信し（Ｓ３３）、無線回線制御局１０２が、選択された空き回線を共用移動局１０６に割り当てる処理を行う（Ｓ３４）。ただし、Ｓ３０の判定処理の結果、割り当て不可能と判定された場合（Ｓ３１で否定判定の場合）又はＳ３２で空き回線が存在しない場合は、システムＢの回線を共用移動局１０６に割り当てることは不可能と判断できるため、無線回線制御局１０７は、空き回線が存在しない旨の応答を無線回線制御局１０２に送信する（Ｓ３５）。そして、無線回線制御局１０２は、Ｓ３５で空き回線が存在しない旨の応答を受信した後、システムＣを相手の候補システムとしてＳ２６〜Ｓ２８と同様の処理を行い、システムＣの無線回線制御局がＳ２９〜Ｓ３３、Ｓ３５と同様の処理を行う。
【００７６】
そして、最終的には無線回線制御局１０２は、割り当て可能な回線が有った時点で当該選択された空き回線を共用移動局１０６に割り当てる処理を行う（Ｓ３４に相当）。一方、最終的に、割り当て可能な回線が無かった場合、無線回線制御局１０２は、共用移動局１０６に無線回線割り当てができない旨を通知して（Ｓ３６に相当）、図１０の処理を終了する。
【００７７】
以上のような図１０の処理により、共用移動局１０６からの無線回線割り当て要求に基づき各システムに対して順番に、空き回線が探索され共用移動局１０６に割り当てられることとなる。
【００７８】
次の図１１の処理例は、システムＡにて接続不可であった場合に、システムＢでの接続を試みる制御を、共用移動局１０６が自律的に、システムＢの無線回線制御局１０７へ無線回線割り当て要求を送信することによって行う態様である。
【００７９】
即ち、図１１に示すように、まず、共用移動局１０６は、システムＡの無線回線制御局１０２に対して、無線基地局１０３を介して無線回線割り当ての要求信号を送信する（Ｓ１０１）。無線回線制御局１０２は、共用移動局１０６から無線回線割り当ての要求信号を受信すると、前述のような割り当て可否判定処理を行う（Ｓ１０２）。この割り当て可否判定処理において無線回線の割り当て可能と判定された場合（Ｓ１０３で肯定判定の場合）、割り当てるべき回線の選択を試み、空き回線が存在するか否かを確認し（Ｓ１０４）、空き回線が存在する場合は、選択された空き回線を共用移動局１０６に割り当てる処理を行う（Ｓ１０５）。
【００８０】
一方、Ｓ１０２の割り当て可否判定処理において無線回線の割り当て不可と判定された場合（Ｓ１０３で否定判定の場合）又はＳ１０４で空き回線が存在しない場合は、システムＡの回線を共用移動局１０６に割り当てることは不可能と判断できるため、無線回線制御局１０２は共用移動局１０６に無線回線割り当てができない旨を通知する（Ｓ１０６）。
【００８１】
なお、システムＡ以外に候補システムが存在しない場合は、図示を省略したが、割り当て可否判定処理（Ｓ１０２）を回避して、割り当てるべき回線の選択を試み、空き回線が存在するか否かを確認する（Ｓ１０４）。空き回線が存在する場合は、選択された空き回線を共用移動局１０６に割り当てる処理を行い（Ｓ１０５）、空き回線が存在しない場合は、共用移動局１０６に無線回線割り当てができない旨を通知して（Ｓ１１５に相当）、図１１の処理を終了する。
【００８２】
さて、Ｓ１０６での通知を受けた共用移動局１０６は、自局が通信可能なシステムのうち次のシステム（システムＢ）が最終候補システムであるか否かを判定する（Ｓ１０７）。このとき共用移動局１０６は、自局の通信可能なシステム情報（システムＡとＢ）を参照することで、システムＢが最終候補システムであると判断し、送信相手のシステムＢが最終候補システムであることを告知する情報（最終候補情報）を無線回線割り当て要求に付加して（Ｓ１０８）、システムＢの無線回線制御局１０７へ割り当て要求信号を送信する（Ｓ１０９）。
【００８３】
無線回線制御局１０７は、共用移動局１０６から割り当て要求信号を受信すると、まず自局（無線回線制御局１０７自身）が最終候補システムであるか否かを、要求信号に最終候補情報が付加されているか否かによって判定する（Ｓ１１０）。このとき無線回線制御局１０７は、上記の最終候補情報が割り当て要求信号に含まれているため、当該最終候補情報によって自局は最終候補システムであることを認識する。
【００８４】
Ｓ１１０で自局は最終候補システムであると判定した場合、割り当て可否判定処理（Ｓ１１１）を回避して、割り当てるべき回線の選択を試みて空き回線が存在するか否かを確認し（Ｓ１１３）、空き回線が存在する場合は、当該無線回線制御局１０７が、選択された空き回線を共用移動局１０６に割り当てる処理を行う（Ｓ１１４）。一方、Ｓ１１３で空き回線が存在しない場合、システムＢの回線を共用移動局１０６に割り当てることは不可能と判断でき、無線回線を割り当てる候補システムが尽きたため、無線回線制御局１０７は、共用移動局１０６に無線回線割り当てができない旨を通知して（Ｓ１１５）、図１１の処理を終了する。
【００８５】
一方、Ｓ１１０でシステムＢが最終候補システムでなく他の候補システム（例えばシステムＣ）が存在する場合、上述した無線回線制御局１０２での処理と同様に、無線回線の割り当て可否判定処理を行う（Ｓ１１１）。判定処理の結果、割り当て可能と判定された場合（Ｓ１１２で肯定判定の場合）、割り当てるべき回線の選択を試み、空き回線が存在するか否かを確認し（Ｓ１１３）、空き回線が存在する場合は、当該無線回線制御局１０７が、選択された空き回線を共用移動局１０６に割り当てる処理を行う（Ｓ１１４）。ただし、Ｓ１１１の判定処理の結果、割り当て不可能と判定された場合（Ｓ１１２で否定判定の場合）又はＳ１１３で空き回線が存在しない場合は、システムＢの回線を共用移動局１０６に割り当てることは不可能と判断できるため、無線回線制御局１０７は、空き回線が存在しない旨の応答を共用移動局１０６に送信する。そして、共用移動局１０６は、システムＢの空き回線が存在しない旨の応答を受信した後、システムＣを相手の候補システムとしてＳ１０７〜Ｓ１０９と同様の処理を行い、システムＣの無線回線制御局がＳ１１０〜Ｓ１１５と同様の処理を行う。
【００８６】
そして、最終的に、割り当て可能な回線が有った時点で、そのシステムの無線回線制御局が空き回線を共用移動局１０６に割り当てる処理を行う（Ｓ１１３に相当）。一方、最終的に、割り当て可能な回線が無かった場合、共用移動局１０６は、無線回線割り当てを中止し、図１１の処理を終了する。
【００８７】
以上のような図１１の処理により、共用移動局１０６からの無線回線割り当て要求に基づき各システムに対して順番に、空き回線が探索され共用移動局１０６に割り当てられることとなる。
【００８８】
ところで、上記の各実施形態での無線回線割り当て制御方法は、１つの方式システムにおける複数の周波数帯域の各々について、当該周波数帯域で通信可能な移動局に対し無線回線を割り当てる際にも、適用することができ、同様の作用・効果を得ることができる。
【００８９】
また、図４〜図９の判定処理は、各方式システムへの無線回線割り当て可否の判定に限定されず、各方式システムにおける複数の周波数帯域の各々について、当該周波数帯域で通信可能な移動局に対し無線回線を割り当てる際にも、適用することができ、同様の作用・効果を得ることができる。
【００９０】
【発明の効果】
以上説明したように、本発明によれば、各方式システムでは、無線ゾーン内における回線使用率、または呼損率に応じて、共用移動局に対する回線割り当ての可否を決定するため、共用移動機の回線使用により専用移動機が使用可能である回線が圧迫され、共用移動局の呼損率と比較して専用移動局の呼損率が上昇することを防止することができる。
【００９１】
また、共用移動局への無線回線割り当てを試みる最終候補の方式システムにおいては、専用移動局と同様に空き無線回線を割り当てるため、共用移動局についても著しい呼損率の上昇を防止することができ、専用移動局を使用するユーザ、および共用移動局を使用するユーザに対し、可能な限り同等の接続品質を提供することができる。
【００９２】
また、本発明は、複数の方式システムの各々に基づく通信を行うための移動局への無線回線の割り当て制御のみならず、１つの方式システムにおける複数の周波数帯域の各々について、当該周波数帯域で通信可能な移動局に対し無線回線を割り当てる際にも、適用することができる。
【００９３】
また、本発明は、各方式システムへの無線回線割り当て可否の判定に限定されず、各方式システムにおける複数の周波数帯域の各々について、当該周波数帯域で通信可能な移動局に対し無線回線を割り当てる際の割り当て可否の判定にも適用することができる。このように本発明は、汎用性が非常に高く有効な技術といえる。
【図面の簡単な説明】
【図１】発明の実施形態に係る複数方式共用システムの構成図である。
【図２】無線回線制御局の構成図である。
【図３】無線回線割り当てに関する処理の第１の例を示す図である。
【図４】割り当て可否判定処理の第１の例を示す流れ図である。
【図５】割り当て可否判定処理の第２の例を示す流れ図である。
【図６】割り当て可否判定処理の第３の例を示す流れ図である。
【図７】割り当て可否判定処理の第４の例を示す流れ図である。
【図８】割り当て可否判定処理の第５の例を示す流れ図である。
【図９】割り当て可否判定処理の第６の例を示す流れ図である。
【図１０】
無線回線割り当てに関する処理の第２の例を示す図である。
【図１１】
無線回線割り当てに関する処理の第３の例を示す図である。
【符号の説明】
１００…複数方式共用システム、１０１…コアネットワーク、１０２、１０７…無線回線制御局、１０３、１０８…無線基地局、１０４、１０９…無線ゾーン、１０５、１１０…専用移動局、１０６…共用移動局、２０１、２０２…送受信部、２０３…制御部、２０４…情報記憶部。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a multiple system sharing system, a wireless line allocation control method and a control device, and more particularly, to a control for each system for performing wireless line allocation control for performing communication based on each of the multiple system systems. The system includes a device, a shared mobile station capable of performing communication based on each of a plurality of system systems, and a dedicated mobile station for each system capable of performing only communication based on one system. The present invention relates to a multi-method shared system, a radio channel assignment control method when each control device assigns a radio channel to a shared mobile station in the multi-method shared system, and a control device constituting the multi-method shared system.
[0002]
Further, the present invention, for each of a plurality of frequency bands in one system, a control device for each frequency band that performs radio channel allocation control to allocate a radio channel to a mobile station that can communicate in the frequency band, In a mobile communication system configured to include a shared mobile station capable of communicating in a plurality of frequency bands and a dedicated mobile station for each frequency band capable of communicating only in one frequency band, each of the control devices may be configured to control the shared mobile station. The present invention relates to a wireless channel assignment control method when assigning a wireless channel to a station. Furthermore, the present invention is also applied to a case where a control device that controls a plurality of frequency bands is provided instead of a control device for each frequency band.
[0003]
[Prior art]
As a typical example of a plurality of mobile communication systems (referred to as "system system" in the present specification), 800 MHz band system and 1500 MHz band system in a digital car telephone system (PDC) currently commercially provided in Japan. There is. As an operation mode of the PDC, a mode in which an 800 MHz system and a 1500 MHz system are independently operated as separate systems was generally used. However, a mobile station capable of using each frequency band of the two systems (hereinafter, a “shared mobile station”) ), The mobile stations are distributed to the two systems, and the mobile stations are distributed and arranged in the two systems at the time of standby and at the start of communication, thereby distributing the traffic and the processing load to the two systems. A shared system of a plurality of systems for the purpose of increasing the user capacity has been considered.
[0004]
[Problems to be solved by the invention]
However, when the sharing scheme is implemented, in each system, a dedicated mobile station (a mobile station that can use only the frequency band of the 800 MHz band system or a mobile station that can use only the frequency band of the 1500 MHz band system) and a shared mobile station are used. And the shared mobile station can be connected to both systems, whereas the dedicated mobile station is limited to only one system, so the capacity of each system and the capacity of each system are allocated. Depending on the number of shared mobile stations used, the use of the shared mobile station's line may squeeze the line that can be used by the dedicated mobile station, and the call loss rate of the dedicated mobile station may be significantly increased as compared to the call loss rate of the shared mobile station. .
[0005]
SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and has a multi-system sharing system capable of preventing an increase in a call loss rate of a dedicated mobile station as compared with a call loss rate of a shared mobile station. It is an object to provide a control method and a control device.
[0006]
[Means for Solving the Problems]
[0010]
In order to achieve the above object, a wireless channel allocation control method according to the present invention Has multiple A control device for each of the system systems that performs radio channel allocation control for performing communication based on each of the system systems; a shared mobile station capable of performing communication based on each of the plurality of system systems; In a multi-system shared system including a dedicated mobile station for each system capable of performing only system-based communication, a radio channel when each controller assigns a radio channel to the shared mobile station An allocation control method, wherein each control device is requested to allocate a wireless channel to the shared mobile station, and if the own device is not a final candidate control device that attempts to allocate a wireless channel, the wireless device is controlled based on predetermined conditions. Is determined, and based on the determination result, the assignment of the wireless channel is controlled. When the assignment of the wireless channel to the shared mobile station is requested, If a control device of the final candidate attempts to allocate a line, to avoid the allocation determination radio channel, and performs allocation of radio line to the shared mobile station.
[0011]
In the radio channel allocation control method according to the present invention, each control device is required to allocate a radio channel to a shared mobile station, and when the device itself is not a final candidate control device that attempts to allocate a radio channel, a predetermined condition is satisfied. Based on the result of the determination, the assignment of the wireless channel is determined, and the assignment of the wireless channel is controlled based on the determination result. Thus, instead of simply unconditionally allocating to a shared mobile station in response to a wireless channel allocation request, it is determined whether or not allocation to the shared mobile station is possible, and the allocation of the wireless channel is controlled based on the determination result. Thus, it is possible to prevent a line that can be used by the dedicated mobile station from being squeezed due to the use of the line of the shared mobile station, thereby preventing the call loss rate of the dedicated mobile station from being increased as compared with the call loss rate of the shared mobile station.
[0012]
On the other hand, when the assignment of the wireless channel to the shared mobile station is requested and the own device is the final candidate control device that attempts to assign the wireless channel, the determination as to whether the wireless channel can be assigned is avoided and the shared mobile station is avoided. Allocate a wireless line to. As a result, it is possible to prevent a remarkable increase in the call blocking rate for the shared mobile station, and to provide the same connection quality as possible to both the user using the dedicated mobile station and the user using the shared mobile station. Can be.
[0013]
The above invention can be described as an invention relating to a multiple system sharing system and an invention relating to a control device. That is, a multiple system sharing system according to the present invention. Has multiple A control device for each of the system systems that performs radio channel allocation control for performing communication based on each of the system systems; a shared mobile station capable of performing communication based on each of the plurality of system systems; A multi-system shared system including a dedicated mobile station for each system capable of performing only system-based communication, wherein each control device transmits a request for allocating a wireless channel to the shared mobile station. Receiving means for receiving, from the shared mobile station, assignability determining means for determining whether wireless channels can be assigned based on predetermined conditions, allocating means for allocating a wireless channel to the shared mobile station, and When receiving the request for allocating a wireless line to the station, and when the own device is not the final candidate control device for allocating the wireless line, Determines whether wireless channels can be allocated, controls the allocation by the allocation unit based on the determination result, receives a wireless channel allocation request to the shared mobile station, and causes the own device to allocate a wireless channel. When the control device is the final candidate control device to be attempted, the control device controls the wireless communication device so as to avoid the wireless link allocation availability determination by the allocation availability determination device and to perform the wireless channel allocation by the allocation device. .
[0014]
Also, the control device according to the present invention Has multiple And a shared mobile station capable of performing communication based on each of the system systems, and a dedicated mobile station for each system capable of performing only communication based on one system, forming a multiple system shared system. A control apparatus for performing radio channel allocation control for performing communication based on a predetermined one of the system systems, and receiving a radio channel allocation request to the shared mobile station from the shared mobile station. Receiving means, assignability determining means for determining whether wireless channels can be allocated based on predetermined conditions, allocating means for allocating a wireless channel to the shared mobile station, and requesting allocation of a wireless channel to the shared mobile station. Is received, and if the own device is not the control device of the final candidate that attempts to allocate the wireless line, To determine whether or not a wireless channel is to be allocated based on the determination result by the allocating means, to receive a request for allocating a wireless channel to the shared mobile station, and to make a final candidate for the device to try to allocate a wireless channel. The control device is characterized in that control means is provided for controlling the assignment of wireless channels by the assignment availability determination means so as to avoid assignment determination of the wireless channels by the assignment availability determination means.
[0015]
Incidentally, the determination as to whether or not a certain control device is the control device of the final candidate may be performed by the control device (own device), or may be performed by the control device that has received the allocation request from the shared mobile station (the call has been accepted. Control device) or a shared mobile station. These three patterns can be described as the invention relating to the wireless channel allocation control method and the invention relating to the multiple system sharing system as follows.
[0016]
An aspect in which the control device determines whether a certain control device is a final candidate control device, below Can be described as follows. That is, According to the present invention In the wireless channel allocation control method, the wireless channel allocation request includes information on a communicable system of the shared mobile station, and each control device performs communication based on the communicable system information of the shared mobile station. It is characterized in that it is determined whether or not the own device is a final candidate control device to try to allocate a wireless channel. Also, According to the present invention In the multi-system shared system, the wireless channel allocation request includes information on a communicable system of the shared mobile station, and each control device performs communication based on the communicable system information of the shared mobile station. And a first final candidate determining means for determining whether or not the own device is a final candidate control device that attempts to allocate a wireless channel.
[0017]
A mode in which the control device that has received the assignment request from the shared mobile station determines whether or not a certain control device is the final candidate control device, below Can be described as follows. That is, According to the present invention In the wireless channel assignment control method, the shared mobile station outputs an assignment request including information on a communicable system of the shared mobile station, and one controller that has received the assignment request transmits a wireless link based on a predetermined condition. And if the result of the determination is unassignable, based on the system information that the shared mobile station can communicate with, based on the system information of the other candidates, the control device of the final candidate which attempts to allocate a radio channel by another candidate control device. Is determined, and the determination information of the final candidate is added to the allocation request and output to another candidate control device. Also, According to the present invention In the multiple-method shared system, the shared mobile station outputs an assignment request including information on a communicable system of the shared mobile station, and when the control device determines that the assignment is not possible by the assignment availability determination unit, A second final candidate determining unit that determines whether or not the other candidate control device is a final candidate control device that attempts to allocate a wireless channel, based on information on a communicable system system of the shared mobile station; Request output means for adding the final candidate determination information to the assignment request and outputting the information to another candidate control device.
[0018]
The form in which the shared mobile station determines whether or not a certain control device is the final candidate control device is below Can be described as follows. That is, According to the present invention In the wireless channel assignment control method, one control device that has received the wireless channel assignment request determines whether or not the wireless channel assignment is possible based on a predetermined condition, and if the determination result indicates that assignment is impossible, the shared result is shared. Notifying the mobile station, the shared mobile station determines whether the other candidate control device is the final candidate control device that attempts to allocate a radio channel based on the communicable system information of its own station. The determination is made, the final candidate determination information is added to the allocation request, and the information is output to another candidate control device. Also, According to the present invention In the multiple-system shared system, the control device further includes a notifying unit that notifies the shared mobile station of the determination result when the allocation is determined by the allocation availability determination unit, wherein the shared mobile station includes: Candidate determining means for determining whether or not the other candidate control device is a final candidate control device that attempts to allocate a wireless channel, based on the communicable system information, and the final candidate determination information. Output means for outputting to the other candidate control devices in addition to the assignment request.
[0019]
By the way, as for the determination as to whether or not the wireless channel can be allocated in each control device, the following aspects can be adopted.
[0020]
That is, In the present invention In each of the control devices, when determining whether or not a wireless line can be allocated, the line usage of all mobile stations indicating the ratio of the number of wireless lines used by all mobile stations to the number of all wireless lines in the wireless zone under the control of the own device. The rate is compared with a first threshold value, and if the line usage rates of all mobile stations are lower than the first threshold value, it is determined that allocation is possible, and the line usage rates of all mobile stations are set to the first threshold. It is characterized in that it is determined that the assignment is impossible when the threshold value is exceeded.
[0021]
Also, In the present invention Each control device determines whether wireless channels can be allocated, and determines whether or not the shared mobile station uses the number of wireless channels used by the shared mobile station with respect to the total number of wireless channels in the wireless zone under its control. The ratio is compared with a second threshold value, and if the line usage rate of the shared mobile station is lower than the second threshold value, it is determined that allocation is possible, and the line usage rate of the shared mobile station is set to the second threshold value. It is characterized in that it is determined that the assignment is impossible when the threshold value is exceeded.
[0022]
Also, In the present invention In each of the control devices, when determining whether or not a wireless line can be allocated, the line usage of all mobile stations indicating the ratio of the number of wireless lines used by all mobile stations to the number of all wireless lines in the wireless zone under the control of the own device. Comparing the rate with the first threshold, and comparing the line usage rate of the shared mobile station, which represents the ratio of the number of wireless links in use by the shared mobile station to the total number of wireless links, with the second threshold, When the line usage rate of all mobile stations is lower than the first threshold value and the line usage rate of the shared mobile station is lower than the second threshold value, it is determined that assignment is possible, and the line usage rate of all mobile stations is determined. Is greater than or equal to a first threshold, or if the line usage rate of the shared mobile station is greater than or equal to a second threshold, it is determined that assignment is impossible.
[0023]
Also, In the present invention In each of the control devices, when determining whether or not a wireless line can be allocated, the line usage of all mobile stations indicating the ratio of the number of wireless lines used by all mobile stations to the number of all wireless lines in the wireless zone under the control of the own device. Comparing the rate with the first threshold, and comparing the line usage rate of the shared mobile station, which represents the ratio of the number of wireless links in use by the shared mobile station to the total number of wireless links, with the second threshold, If the line usage rate of all mobile stations is lower than the first threshold or the line usage rate of the shared mobile station is lower than the second threshold, it is determined that assignment is possible, and the line usage of all mobile stations is determined. When the rate is equal to or higher than a first threshold and the line usage rate of the shared mobile station is equal to or higher than a second threshold, it is determined that assignment is impossible.
[0024]
Also, In the present invention In each of the control devices, when determining whether or not the wireless channel can be allocated, the control device allocates the wireless channel to the dedicated mobile station in response to the number of wireless channel allocation requests from the dedicated mobile station within a fixed time within the wireless zone under the control of the control device. The loss probability of the dedicated mobile station, which represents the ratio of the number of failures, is compared with a third threshold, and if the loss probability of the dedicated mobile station is lower than the third threshold, it is determined that assignment is possible. When the call loss rate is equal to or more than a third threshold value, it is determined that assignment is impossible.
[0025]
Also, In the present invention In each of the control devices, when determining whether or not the wireless channel can be allocated, the control device allocates the wireless channel to the dedicated mobile station in response to the number of wireless channel allocation requests from the dedicated mobile station within a fixed time within the wireless zone under the control of the control device. The call loss rate of the dedicated mobile station, which represents the ratio of the number of failures, is represented by the ratio of the number of failures in allocating a wireless line to the shared mobile station to the number of wireless line allocation requests from the shared mobile station within a fixed time within the wireless zone. Compared to the loss probability of the mobile station, if the loss probability of the dedicated mobile station is equal to or less than the loss probability of the shared mobile station, it is determined that assignment is possible. If the loss probability of the dedicated mobile station is higher than the loss probability of the shared mobile station, it is determined that assignment is impossible. It is characterized by the following.
[0026]
By the way, the present invention is based on the same principle as that of the above-described radio channel assignment control method, and also assigns a radio channel to a mobile station that can communicate in the frequency band for each of a plurality of frequency bands in one system. , And the same operation and effect can be obtained.
[0027]
That is, in the wireless channel allocation control method according to the twelfth aspect, for each of a plurality of frequency bands in one system, wireless channel allocation control is performed to allocate a wireless channel to a mobile station that can communicate in the frequency band. A mobile communication system including a control device, a shared mobile station capable of communicating in a plurality of frequency bands, and a dedicated mobile station for each frequency band capable of communicating in only one frequency band; Is a radio channel allocation control method when allocating a radio channel to the shared mobile station, wherein the controller, when requested to allocate a radio channel to the shared mobile station, based on a predetermined condition, It is characterized in that whether or not the assignment is possible is determined, and the assignment of the wireless channel is controlled based on the determination result.
[0028]
Here, the case where a control device exists for each frequency band can be described as claim 13. That is, in the wireless channel allocation control method according to the thirteenth aspect, for each of a plurality of frequency bands in one system, wireless channel allocation control for allocating a wireless channel to a mobile station communicable in the frequency band is performed. A mobile communication system including a control device for each frequency band, a shared mobile station capable of communicating in a plurality of frequency bands, and a dedicated mobile station for each frequency band capable of communicating only in one frequency band. A control method for assigning a radio channel to the shared mobile station, wherein each control device, when requested to assign a radio channel to the shared mobile station, satisfies a predetermined condition. It is characterized in that whether or not the wireless channel can be allocated is determined based on the determination, and the allocation of the wireless channel is controlled based on the determination result.
[0029]
That is, according to the present invention, A wireless channel allocation control method includes, for each of a plurality of frequency bands in one system, a control device for each frequency band that performs wireless channel allocation control for allocating a wireless channel to a mobile station that can communicate in the frequency band. In a mobile communication system configured to include a shared mobile station capable of communicating in a plurality of frequency bands and a dedicated mobile station for each frequency band capable of communicating only in one frequency band, What is claimed is: 1. A wireless channel assignment control method for assigning a wireless channel to a mobile station, wherein each control device is requested to assign a wireless channel to the shared mobile station and controls a final candidate for which the own device attempts to assign a wireless channel. If the device is not a device, the wireless communication device determines whether wireless channels can be allocated based on predetermined conditions, and controls wireless channel allocation based on the determination result. When the assignment of a wireless line to a station is requested and the own device is a final candidate control device that attempts to assign a wireless line, it is possible to avoid determining whether or not to assign a wireless line, and to assign the wireless line to the shared mobile station. It is characterized by performing.
[0030]
Also, According to the present invention In the wireless channel allocation control method, the wireless channel allocation request includes information on a communicable frequency band of the shared mobile station, and each control device performs communication based on the communicable frequency band information of the shared mobile station. It is characterized in that it is determined whether or not the own device is a final candidate control device to try to allocate a wireless channel.
[0031]
Also, According to the present invention In the wireless channel assignment control method, the shared mobile station outputs an assignment request including information on a communicable frequency band of the shared mobile station, and one control device that has received the assignment request transmits a wireless link based on a predetermined condition. Is determined, if the determination result indicates that allocation is not possible, based on the communicable frequency band information of the shared mobile station, based on the information of the communicable frequency band of the shared mobile station, the control device of the final candidate which attempts to allocate a wireless channel by another candidate control device Is determined, and the determination information of the final candidate is added to the allocation request and output to another candidate control device.
[0032]
Also, According to the present invention In the wireless channel assignment control method, one control device that has received the wireless channel assignment request determines whether or not the wireless channel assignment is possible based on a predetermined condition, and if the determination result indicates that assignment is impossible, the shared result is shared. Notify the mobile station, the shared mobile station, based on the communicable frequency band information of its own station, whether or not the other candidate control device is the final candidate control device to try to allocate the radio line whether or not The determination is made, the final candidate determination information is added to the allocation request, and the information is output to another candidate control device.
[0033]
By the way, as for the determination as to whether or not the wireless channel can be allocated in each control device, the following aspects can be adopted.
[0034]
That is, In the present invention In the determination of the applicability of the radio channel, the control device determines the ratio of the number of radio channels used by all the mobile stations to the number of all radio channels in the frequency band to be controlled by the control device. Is compared with a first threshold value, and when the line usage rates of all mobile stations are lower than the first threshold value, it is determined that assignment is possible, and the line usage rates of all mobile stations are equal to a first threshold. When the value is equal to or larger than the value, it is determined that assignment is impossible.
[0035]
Also, In the present invention In the determination of the applicability of the radio channel, the control device determines the ratio of the number of radio channels used by the shared mobile station to the total number of radio channels in the frequency band to be controlled by the control device. Is compared with a second threshold value, and if the line usage rate of the shared mobile station is lower than the second threshold value, it is determined that assignment is possible, and the line usage rate of the shared mobile station is set to the second threshold. When the value is equal to or larger than the value, it is determined that assignment is impossible.
[0036]
Also, In the present invention In the determination of the applicability of the radio channel, the control device determines the ratio of the number of radio channels used by all the mobile stations to the number of all radio channels in the frequency band to be controlled by the control device. Is compared with the first threshold value, and the line usage rate of the shared mobile station, which represents the ratio of the number of wireless lines used by the shared mobile station to the total number of wireless lines, is compared with the second threshold value. If the line usage rate of all mobile stations is lower than the first threshold value and the line usage rate of the shared mobile station is lower than the second threshold value, it is determined that assignment is possible, and the line usage rate of all mobile stations is determined. If the rate is equal to or greater than a first threshold or the line usage rate of the shared mobile station is equal to or greater than a second threshold, it is determined that assignment is impossible.
[0037]
Also, In the present invention In the determination of the applicability of the radio channel, the control device determines the ratio of the number of radio channels used by all the mobile stations to the number of all radio channels in the frequency band to be controlled by the control device. Is compared with the first threshold value, and the line usage rate of the shared mobile station, which represents the ratio of the number of wireless lines used by the shared mobile station to the total number of wireless lines, is compared with the second threshold value. If the line usage rate of all mobile stations is lower than the first threshold value or the line usage rate of the shared mobile station is lower than the second threshold value, it is determined that assignment is possible, When the usage rate is equal to or higher than the first threshold value and the line usage rate of the shared mobile station is equal to or higher than the second threshold value, it is determined that assignment is impossible.
[0038]
Also, In the present invention In the determination of whether or not the wireless channel can be allocated, the control device fails to allocate the wireless channel to the dedicated mobile station in response to the number of wireless channel allocation requests from the dedicated mobile station within a certain time in the frequency band to be controlled by the control device. The loss probability of the dedicated mobile station, which represents the ratio of the number, is compared with a third threshold, and if the loss probability of the dedicated mobile station is lower than the third threshold, it is determined that allocation is possible, and the loss probability of the dedicated mobile station is determined. Is determined to be unassignable when the threshold value is greater than or equal to a third threshold value.
[0039]
Also, In the present invention In the determination of whether or not the wireless channel can be allocated, the control device fails to allocate the wireless channel to the dedicated mobile station in response to the number of wireless channel allocation requests from the dedicated mobile station within a certain time in the frequency band to be controlled by the control device. The call loss rate of the dedicated mobile station, which represents the ratio of the number of dedicated mobile stations, is defined as the ratio of the number of failures in allocating a wireless channel to the shared mobile station to the number of wireless channel allocation requests from the shared mobile station within a fixed time within the wireless zone. Compared to the loss probability of the station, it is determined that assignment is possible when the loss probability of the dedicated mobile station is equal to or less than the loss probability of the shared mobile station, and it is determined that allocation is not possible when the loss probability of the dedicated mobile station is higher than the loss probability of the shared mobile station. It is characterized by.
[0040]
As described above, the present invention not only controls the assignment of a radio channel to a mobile station for performing communication based on each of a plurality of system systems, but also controls each of a plurality of frequency bands in one system. The present invention can also be applied to the case where a wireless channel is allocated to a mobile station that can communicate with the mobile station.
[0041]
Further, the present invention is not limited to the determination as to whether or not a wireless channel can be allocated to each scheme system. For each of a plurality of frequency bands in each scheme system, when assigning a wireless channel to a mobile station that can communicate in the frequency band. Can also be applied to the determination of the assignment availability. As described above, the present invention can be said to be a highly versatile and effective technology.
[0042]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0043]
[Configuration example of the present embodiment]
FIG. 1 shows a configuration diagram of a multiple system sharing system 100 in the present embodiment. As shown in FIG. 1, two system systems (systems A and B) coexist in the multiple system sharing system 100. As for the system A, the radio network controller 102 that controls the system A is connected to the core network 101, and the radio base station 103 is connected to the radio network controller 102. In a wireless zone 104 formed by the wireless base station 103, there are a dedicated mobile station 105 that can communicate only with the system A and a shared mobile station 106 that can communicate with each of the systems A and B. As for the system B, the radio network controller 107 that controls the system B is connected to the core network 101, and the radio base station 108 is connected to the radio network controller 107. In a wireless zone 109 formed by the wireless base station 108, there are a dedicated mobile station 110 that can communicate only with the system B and a shared mobile station 106 that can communicate with each of the systems A and B. Note that the radio network controllers 102 and 107 correspond to the control device according to the present invention.
[0044]
FIG. 2 shows a configuration diagram of the radio network controller 102. As shown in FIG. 2, the radio network controller 102 includes a transmitting / receiving unit 201 connected to the core network 101 for transmitting / receiving signals to / from the core network 101, a radio base station 103, a dedicated mobile station 105, A transmission / reception unit 202 connected to the radio base station 103 for transmitting / receiving signals to / from the mobile station 106, and an information storage unit storing a large amount of information including a threshold value relating to a radio channel usage rate and a threshold value relating to a call loss rate And a control unit 203 that controls and monitors the operation of each of these components. The control unit 203 performs, for example, the management of the wireless channel, the number of requests for wireless channel allocation, the number of successful and failed wireless channel allocations, and stores the information in the information storage unit 204 and the wireless communication described later. It performs line allocation control and the like. The configuration of the radio network controller 107 is the same as that of FIG.
[0045]
[Example of wireless line assignment processing]
Hereinafter, processing related to wireless channel assignment in the present embodiment will be described. FIG. 3 shows a flow from when the shared mobile station 106 waiting in the system A requests assignment of a wireless channel to when the assigned wireless channel is determined.
[0046]
As shown in FIG. 3, first, shared mobile station 106 transmits a request signal for radio channel assignment to radio network controller 102 of system A via radio base station 103 (S01). Upon receiving the request signal for radio channel assignment from shared mobile station 106, radio channel control station 102 first determines that it is the last candidate system among the systems with which radio station control station 102 itself can communicate with shared mobile station 106. It is determined whether or not there is (S02). At this time, the radio network controller 102 refers to, for example, the communicable system information of the shared mobile station 106 included in the radio channel assignment request signal, and determines that the request signal is not a transfer from another radio network controller. Based on the fact that the system B is directly received from the shared mobile station 106, it is determined that the system B other than the system A remains as a candidate system, and that the own station is not a final candidate system.
[0047]
If the own station determines that the system is not the final candidate system, it determines whether wireless channels can be allocated to the shared mobile station 106 (S03). Various processes shown in FIGS. 4 to 9 to be described later can be adopted as the assignment availability determination process. The processing content will be described later.
[0048]
If it is determined in the allocation availability determination process in S03 that the wireless channel can be allocated (if the determination is affirmative in S04), an attempt is made to select a line to be allocated, and it is checked whether or not there is a free line (S06). If a line exists, a process of allocating the selected free line to the shared mobile station 106 is performed (S08). In the case where the own station is the final candidate system in S02, a flow for avoiding the assignment availability determination processing (S03) is adopted. This advantage will be described later.
[0049]
On the other hand, if it is determined that the wireless channel cannot be allocated in the allocation availability determination processing in S03 (if the determination is negative in S04) or if there is no free line in S06, the line of the system A is allocated to the shared mobile station 106. Therefore, the radio network controller 102 transmits the shared channel to the radio network controller 107 of the system B via the core network 101 in order to allocate a channel of another candidate system (system B). A request signal for wireless channel allocation is transmitted to the mobile station 106 (S05, S07).
[0050]
In the case where there is no candidate system other than the system A, the illustration is omitted. However, the assignment availability determination processing (S03) is avoided, a line to be assigned is selected, and it is confirmed whether or not there is a free line. (S06). If there is a free line, a process of allocating the selected free line to the shared mobile station 106 is performed (S08). If there is no free line, the shared mobile station 106 is notified that the wireless line cannot be allocated. (Corresponding to S16), and the processing in FIG. 3 ends.
[0051]
Upon receiving the radio channel assignment request signal from the radio network controller 102, the radio network controller 107 first determines that the local station (the radio network controller 107 itself) is the final candidate system among the systems that can be communicated by the shared mobile station 106. Is determined (S09). At this time, the radio network controller 107 refers to, for example, the communicable system information (here, systems A and B) of the shared mobile station 106 included in the radio channel assignment request signal, and Based on the fact that it has been received from the radio network controller 102, it can be determined that no candidate system remains other than the system B of the own station, so that the own station is determined to be the final candidate system. Regarding the system information with which the shared mobile station 106 can communicate, the radio network controller 102 deletes the information of the system A before transmitting the radio channel assignment request signal to the radio network controller 107 in S05 or S07. , May be operated to leave only the information of the system B.
[0052]
If the own station is determined to be the final candidate system in S09, the assignment feasibility determination process (S10) is bypassed, an attempt is made to select a line to be allocated, and it is confirmed whether or not there is a free line (S12). If there is a free line, a response to the effect that there is a free line is transmitted to the radio network controller 102 (S13), and the radio network controller 102 performs a process of allocating the selected free channel to the shared mobile station 106. Perform (S14). On the other hand, if there is no free line in S12, it can be determined that it is impossible to allocate the system B line to the shared mobile station 106, so the radio network controller 107 sends a response to the effect that there is no free line to the radio line control. The data is transmitted to the station 102 (S15). Upon receiving this response, the radio network controller 102 notifies the shared mobile station 106 that the radio channel cannot be allocated (S16), and ends the processing in FIG.
[0053]
On the other hand, when the system B is not the final candidate system but another candidate system (for example, the system C) exists in S09, the wireless channel allocation availability determination process is performed in the same manner as the above-described process in the wireless network control station 102 ( S10). As a result of the determination processing, when it is determined that allocation is possible (in the case of an affirmative determination in S11), an attempt is made to select a line to be allocated, and it is confirmed whether or not there is a free line (S12). Transmits a response to the effect that there is an idle line to the radio network controller 102 (S13), and the radio network controller 102 performs a process of allocating the selected empty line to the shared mobile station 106 (S14). However, as a result of the determination processing in S10, when it is determined that allocation is not possible (in the case of a negative determination in S11) or when there is no free line in S12, it is not possible to allocate the system B line to the shared mobile station 106. Since it can be determined that it is possible, the radio network controller 107 requests the radio network controller of the system C via the core network 101 to allocate the radio network to the shared mobile station 106 in order to allocate the channel of the system C. Send a signal.
[0054]
Finally, when there is a line that can be allocated, the radio network controller of the system notifies the radio network controller 102 of the system A (corresponding to S13), and the radio network controller 102 A line is allocated (corresponding to S14). On the other hand, if there is finally no line that can be allocated, the last system notifies the radio network controller 102 of the system A that there is no available channel (corresponding to S15), and the radio network controller 102 The station 106 is notified that the line cannot be allocated (corresponding to S16), and the processing in FIG. 3 ends.
[0055]
According to the processing of FIG. 3 as described above, a free line is searched for each system in order based on the wireless channel allocation request from the shared mobile station 106 and assigned to the shared mobile station 106.
[0056]
[Various Embodiments Regarding Assignment Availability Determination Processing]
By the way, the present invention does not simply allocate an empty line to the shared mobile station 106, but performs an allocation availability determination process described later in S03 and S10, and controls the allocation to the shared mobile station 106 based on the determination result. It is characterized by the following. Hereinafter, various aspects of the assignment availability determination processing will be described with reference to FIGS. 4 to 9.
[0057]
In the processing example of FIG. 4, the line usage rates of all the mobile stations are compared with a predetermined first threshold value, and it is determined whether the line usage rates of all the mobile stations are lower than the first threshold value. (S41). Here, the line usage rate of all mobile stations is the ratio of the number of lines used by all mobile stations to the number of all wireless lines in the wireless zone. If the line usage rates of all the mobile stations are lower than the first threshold value in S41, it is determined that the wireless channels can be allocated (S42), and the line usage rates of all the mobile stations are reduced to the first threshold value. In the above case, it is determined that the wireless channel cannot be allocated (S43). By performing such a determination process, the probability that the dedicated mobile station 105 or the like secures a wireless channel relative to the shared mobile station 106 increases, and it is possible to prevent an increase in the call blocking rate of the dedicated mobile station 105 or the like. .
[0058]
In the processing example of FIG. 5, the line usage rate of the shared mobile station is compared with a predetermined second threshold value, and it is determined whether the line usage rate of the shared mobile station is lower than the second threshold value. (S51). Here, the line usage rate of the shared mobile station is a ratio of the number of lines used by the shared mobile station to the total number of wireless lines in the wireless zone. If the line usage rate of the shared mobile station is lower than the second threshold value in S51, it is determined that the wireless channel can be allocated (S52), and the line usage rate of the shared mobile station is reduced to the second threshold value. In the above case, it is determined that the wireless channel cannot be allocated (S53). By performing such a determination process, the probability that the dedicated mobile station 105 or the like secures a wireless channel relative to the shared mobile station 106 increases, and it is possible to prevent an increase in the call blocking rate of the dedicated mobile station 105 or the like. .
[0059]
In the processing example of FIG. 6, first, the line usage rates of all the mobile stations are compared with a predetermined first threshold value, and it is determined whether the line usage rates of all the mobile stations are lower than the first threshold value. A determination is made (S61). Here, the line usage rate of all mobile stations is the ratio of the number of lines used by all mobile stations to the number of all wireless lines in the wireless zone. If the line usage rates of all mobile stations are lower than the first threshold value in S61, the process proceeds to S62, where the line usage rate of the shared mobile station is compared with a predetermined second threshold value, and the shared mobile station It is determined whether the line usage rate is lower than the second threshold value. Here, the line usage rate of the shared mobile station is a ratio of the number of lines used by the shared mobile station to the total number of wireless lines in the wireless zone. If the line usage rate of the shared mobile station is lower than the second threshold value in S62, it is determined that a wireless channel can be allocated (S63).
[0060]
On the other hand, if the line usage rate of all mobile stations is equal to or more than the first threshold value in S61, or if the line usage rate of the shared mobile station is equal to or more than the second threshold value in S62, it is determined that the wireless channel cannot be allocated. A determination is made (S64). By performing such determination processing, when the line usage rate of all mobile stations is lower than the first threshold value and the line usage rate of the shared mobile station is lower than the second threshold value, Is determined to be assignable, and when the line usage rate of all mobile stations is equal to or higher than the first threshold value or when the line usage rate of the shared mobile station is equal to or higher than the second threshold value, it is determined that the wireless channel cannot be allocated. As a result, the probability that the dedicated mobile station 105 or the like secures a wireless channel relative to the shared mobile station 106 is increased, and an increase in the call loss rate of the dedicated mobile station 105 or the like can be prevented.
[0061]
In the processing example of FIG. 7, first, the line usage rates of all the mobile stations are compared with a predetermined first threshold value, and it is determined whether the line usage rates of all the mobile stations are lower than the first threshold value. A determination is made (S71). Here, the line usage rate of all mobile stations is the ratio of the number of lines used by all mobile stations to the number of all wireless lines in the wireless zone. If the line usage rates of all the mobile stations are lower than the first threshold value in S71, the process proceeds to S73, and it is determined that the wireless channel can be allocated. On the other hand, if the line usage rates of all the mobile stations are equal to or higher than the first threshold value in S71, the process proceeds to S72, where the line usage rates of the shared mobile stations are compared with a predetermined second threshold value. It is determined whether or not the line usage rate is lower than the second threshold value. Here, the line usage rate of the shared mobile station is a ratio of the number of lines used by the shared mobile station to the total number of wireless lines in the wireless zone. If the line usage rate of the shared mobile station is lower than the second threshold value in S72, it is determined that the wireless channel can be allocated (S73).
[0062]
If the line usage rate of the shared mobile station is equal to or higher than the second threshold value in S72, it is determined that the wireless channel cannot be allocated (S74). By performing such determination processing, when the line usage rate of all mobile stations is lower than the first threshold value or the line usage rate of the shared mobile station is lower than the second threshold value, If it is determined that the line can be allocated and the line usage rate of all mobile stations is equal to or higher than the first threshold value and the line usage rate of the shared mobile station is equal to or higher than the second threshold value, the wireless line cannot be allocated. Therefore, the probability that the dedicated mobile station 105 or the like secures a wireless channel relative to the shared mobile station 106 increases, and it is possible to prevent the call loss rate of the dedicated mobile station 105 or the like from increasing.
[0063]
In the processing example of FIG. 8, the loss probability of the dedicated mobile station is compared with a predetermined third threshold value, and it is determined whether the loss probability of the dedicated mobile station is lower than the third threshold value (S81). . Here, the call loss rate of the dedicated mobile station is the ratio of the number of failures in allocating a wireless channel to a dedicated mobile station to the number of requests for allocating a wireless channel from the dedicated mobile station within a fixed time in a wireless zone. If the call loss rate of the dedicated mobile station is lower than the third threshold value in S81, it is determined that the radio channel can be allocated (S82). If the call loss rate of the dedicated mobile station is equal to or more than the third threshold value, Then, it is determined that the wireless channel cannot be allocated (S83). By performing such a determination process, the call loss rate of the dedicated mobile station falls within the allowable fixed value or less, and an increase in the call loss rate of the dedicated mobile station can be prevented.
[0064]
In the processing example of FIG. 9, the call loss rate of the dedicated mobile station is compared with the call loss rate of the shared mobile station, and it is determined whether the call loss rate of the dedicated mobile station is equal to or less than the call loss rate of the shared mobile station (S91). Here, the call blocking rate of the dedicated mobile station is a ratio of the number of times of failure of wireless channel assignment to the dedicated mobile station to the number of wireless channel assignment requests from the dedicated mobile station within a certain time in the wireless zone, and The station call loss rate is the ratio of the number of failures in allocating a wireless channel to a shared mobile station to the number of requests for allocating a wireless channel from a shared mobile station within a fixed time within a wireless zone. If the call loss rate of the dedicated mobile station is equal to or less than the call loss rate of the shared mobile station in S91, it is determined that the wireless channel can be assigned (S92). If the call loss rate of the dedicated mobile station is higher than the call loss rate of the shared mobile station, the wireless channel is assigned. It is determined to be impossible (S93). By performing such determination processing, the call loss rate of the dedicated mobile station becomes equal to or less than the call loss rate of the shared mobile station, and the connection quality between the dedicated mobile station and the shared mobile station can be kept as equal as possible.
[0065]
According to the above-described wireless channel assignment process of FIG. 3 and the determination processes of FIGS. 4 to 9, the shared mobile station is used to determine whether or not to assign a shared mobile station according to the line usage rate or the call blocking rate in the wireless zone. It is possible to prevent a line in which the dedicated mobile station can be used from being pressed by the use of the line of the mobile station, thereby preventing the call loss rate of the dedicated mobile station from increasing as compared with the call loss rate of the shared mobile station.
[0066]
Also, in the final candidate system (system B in FIG. 3) that attempts to allocate a wireless channel to the shared mobile station, the allocation availability determination process (S10 in FIG. 3) is avoided, and an idle wireless channel is allocated in the same manner as the dedicated mobile station. Because of the allocation, it is possible to prevent a remarkable rise in the call blocking rate even for the shared mobile station, and to provide the same connection quality as possible to the user using the dedicated mobile station and the user using the shared mobile station. it can.
[0067]
[Another Embodiment Regarding Wireless Line Assignment Processing]
By the way, for the wireless channel assignment processing in FIG. 3, another processing mode as shown in FIGS. 10 and 11 can be adopted. Hereinafter, these processes will be described with reference to the drawings.
[0068]
The processing example of FIG. 10 is a mode in which the radio network controller 102 that first receives a request from the shared mobile station 106 manages the allocation of radio channels. That is, when the wireless network control station 102 determines that the wireless channel cannot be allocated by itself, and transmits a wireless channel allocation request to the wireless network control station 107 of another system (system B), the other party (system B) ) Is a final candidate system, and in the case of a final candidate system, information notifying that system B is a final candidate system (final candidate information) is added to the wireless channel allocation request and transmitted. It is.
[0069]
That is, as shown in FIG. 10, first, the shared mobile station 106 transmits a wireless channel assignment request signal to the wireless network control station 102 of the system A via the wireless base station 103 (S21). The radio network controller 102 receives a radio channel assignment request signal from the shared mobile station 106. Although not shown here, the radio network controller 102 first determines whether or not its own station (the radio network controller 102 itself) is the final candidate system among the systems with which the shared mobile station 106 can communicate. . At this time, for example, referring to the communicable system information of the shared mobile station 106 included in the request signal for wireless channel assignment, the request signal is directly received from the shared mobile station 106 instead of being transferred from another wireless channel control station. It can be determined from the fact that the system B other than the system A remains as a candidate system, and the own station can be determined not to be the final candidate system.
[0070]
Then, the radio network controller 102 performs the assignment availability determination processing as described above (S22). If it is determined in this allocation availability determination process that the wireless line can be allocated (if the determination is affirmative in S23), the selection of the line to be allocated is attempted, and it is confirmed whether or not there is a free line (S24). If there is, a process of allocating the selected free line to the shared mobile station 106 is performed (S25).
[0071]
On the other hand, if it is determined in the allocation availability determination process in S22 that the wireless channel cannot be allocated (in the case of a negative determination in S23) or if there is no free channel in S24, the system A line is allocated to the shared mobile station 106. Therefore, in order to allocate a line of another candidate system (system B), the radio network controller 102 determines that the system B is the final candidate system among the systems that can be communicated by the shared mobile station 106. It is determined whether or not there is (S26). At this time, the radio network controller 102 refers to the communicable system information (systems A and B) of the shared mobile station 106 included in the request signal for radio channel allocation, so that the system B is the final candidate system. It is determined that there is, and information (final candidate information) notifying that the system B of the transmission partner is the final candidate system is added to the wireless channel allocation request (S27), and the wireless channel of the system B is transmitted via the core network 101. An assignment request signal is transmitted to the control station 107 (S28).
[0072]
In the case where there is no candidate system other than the system A, although illustration is omitted, the assignment availability determination processing (S22) is avoided, a line to be assigned is tried, and it is confirmed whether or not there is a free line. (S24). If there is a free line, a process of allocating the selected free line to the shared mobile station 106 is performed (S25), and if there is no free line, the shared mobile station 106 is notified that radio lines cannot be allocated. (Corresponding to S36), the processing in FIG. 10 ends.
[0073]
When the radio network controller 107 receives the assignment request signal from the radio network controller 102, it first determines whether or not its own station (the radio network controller 107 itself) is a final candidate system in the request signal. Is determined (S29). At this time, since the final candidate information is included in the allocation request signal, the radio network controller 107 recognizes that the own station is a final candidate system based on the final candidate information.
[0074]
When the own station is determined to be the final candidate system in S29, the assignment avoidance determination processing (S30) is bypassed, an attempt is made to select a line to be assigned, and it is confirmed whether or not there is a free line (S32). If there is a free line, a response to the effect that there is a free line is transmitted to the radio network controller 102 (S33), and the radio network controller 102 performs a process of allocating the selected free channel to the shared mobile station 106. Perform (S34). On the other hand, if there is no free line in S32, it can be determined that it is impossible to allocate the system B line to the shared mobile station 106. Therefore, the radio line control station 107 sends a response to the effect that there is no free line to the radio line control. The data is transmitted to the station 102 (S35). Upon receiving this response, the radio network controller 102 notifies the shared mobile station 106 that radio channels cannot be allocated due to the exhaustion of candidate systems for radio channel allocation (S36), and ends the processing in FIG.
[0075]
On the other hand, if the system B is not the final candidate system but another candidate system (for example, the system C) exists in S29, the wireless channel allocation availability determination process is performed in the same manner as the above-described process in the wireless network control station 102 ( S30). As a result of the determination processing, when it is determined that allocation is possible (in the case of an affirmative determination in S31), selection of a line to be allocated is attempted, and it is confirmed whether or not there is a free line (S32). Transmits a response to the effect that an empty line exists to the radio network controller 102 (S33), and the radio network controller 102 performs a process of allocating the selected empty channel to the shared mobile station 106 (S34). However, as a result of the determination processing in S30, when it is determined that allocation is not possible (in the case of negative determination in S31) or when there is no free line in S32, it is not possible to allocate the system B line to the shared mobile station 106. Since it can be determined that it is possible, the radio network controller 107 transmits a response to the effect that there is no free channel to the radio network controller 102 (S35). Then, after receiving the response indicating that there is no vacant line in S35, the radio network controller 102 performs the same processing as in S26 to S28 with the system C as a partner candidate system, and the radio network controller of the system C The same processing as in S29 to S33 and S35 is performed.
[0076]
Finally, when there is a line that can be allocated, the radio network controller 102 performs a process of allocating the selected free channel to the shared mobile station 106 (corresponding to S34). On the other hand, when there is finally no line that can be assigned, the radio network controller 102 notifies the shared mobile station 106 that the radio channel cannot be allocated (corresponding to S36), and ends the processing of FIG. .
[0077]
According to the processing of FIG. 10 described above, a free line is searched for and sequentially assigned to each shared system for each system based on the wireless channel assignment request from the shared mobile station 106.
[0078]
In the following processing example of FIG. 11, when connection is not possible in system A, shared mobile station 106 autonomously performs control to attempt connection in system B to radio circuit control station 107 in system B. In this mode, the request is transmitted by transmitting a line assignment request.
[0079]
That is, as shown in FIG. 11, first, the shared mobile station 106 transmits a radio channel assignment request signal to the radio network controller 102 of the system A via the radio base station 103 (S101). Upon receiving the wireless channel assignment request signal from the shared mobile station 106, the radio network controller 102 performs the above-described assignment availability determination processing (S102). If it is determined in this allocation availability determination processing that the wireless channel can be allocated (if the determination is affirmative in S103), an attempt is made to select a line to be allocated, and it is confirmed whether or not there is a free line (S104). If there is, a process of allocating the selected free line to the shared mobile station 106 is performed (S105).
[0080]
On the other hand, when it is determined that the wireless channel cannot be allocated in the allocation permission determination process in S102 (in the case of a negative determination in S103) or when there is no free line in S104, the line of the system A is allocated to the shared mobile station 106. Therefore, the radio network controller 102 notifies the shared mobile station 106 that the radio channel cannot be allocated (S106).
[0081]
In the case where there is no candidate system other than the system A, although illustration is omitted, the assignment availability determination processing (S102) is bypassed, an attempt is made to select a line to be assigned, and it is confirmed whether or not there is a free line. (S104). If there is a free line, a process of allocating the selected free line to the shared mobile station 106 is performed (S105). If there is no free line, the shared mobile station 106 is notified that the wireless line cannot be allocated. (Corresponding to S115), and the processing in FIG. 11 ends.
[0082]
The shared mobile station 106 that has received the notification in S106 determines whether the next system (system B) among the systems with which the mobile station can communicate is the final candidate system (S107). At this time, the shared mobile station 106 determines that the system B is the final candidate system by referring to the system information (systems A and B) with which the mobile station 106 can communicate, and the system B of the transmission partner is the final candidate system. The information (final candidate information) notifying the presence is added to the wireless channel assignment request (S108), and an assignment request signal is transmitted to the wireless channel control station 107 of the system B (S109).
[0083]
Upon receiving the allocation request signal from the shared mobile station 106, the radio network controller 107 first determines whether or not the own station (the radio network controller 107 itself) is a final candidate system by adding final candidate information to the request signal. It is determined based on whether or not there is (S110). At this time, since the final candidate information is included in the allocation request signal, the radio network controller 107 recognizes that the own station is a final candidate system based on the final candidate information.
[0084]
If the own station is determined to be the final candidate system in S110, the assignment avoidance determination process (S111) is bypassed, a line to be assigned is selected, and it is confirmed whether or not there is a free line (S113). If there is a free line, the radio network controller 107 performs a process of allocating the selected free line to the shared mobile station 106 (S114). On the other hand, if there is no free line in S113, it can be determined that it is impossible to allocate the system B line to the shared mobile station 106, and since the candidate system for allocating the wireless line is exhausted, the wireless channel control station 107 Notifying to 106 that wireless channel allocation is not possible (S115), the processing in FIG. 11 ends.
[0085]
On the other hand, when the system B is not the final candidate system but another candidate system (for example, the system C) exists in S110, the wireless channel allocation availability determination process is performed in the same manner as the above-described process in the wireless channel control station 102 ( S111). As a result of the determination processing, when it is determined that allocation is possible (in the case of a positive determination in S112), an attempt is made to select a line to be allocated, and it is confirmed whether or not there is a free line (S113). Performs a process in which the radio network controller 107 allocates the selected free channel to the shared mobile station 106 (S114). However, as a result of the determination processing in S111, when it is determined that allocation is not possible (in the case of negative determination in S112) or when there is no free line in S113, it is not possible to allocate the system B line to the shared mobile station 106. Since it can be determined that it is possible, the radio network controller 107 sends a response to the effect that no free channel exists to the shared mobile station 106. Then, after receiving a response indicating that there is no free line in system B, shared mobile station 106 performs the same processing as in steps S107 to S109 with system C as a candidate system of the other party, and the radio line control station of system C The same processing as S110 to S115 is performed.
[0086]
Finally, when there is a line that can be allocated, the radio network controller of the system performs a process of allocating an empty line to the shared mobile station 106 (corresponding to S113). On the other hand, when there is finally no line that can be assigned, shared mobile station 106 stops the wireless line assignment and ends the processing in FIG.
[0087]
According to the processing of FIG. 11 as described above, a free line is searched for and sequentially assigned to the shared mobile station 106 for each system based on the wireless channel allocation request from the shared mobile station 106.
[0088]
By the way, the radio channel allocation control method in each of the above embodiments is also applied to each of a plurality of frequency bands in one system when radio channels are allocated to mobile stations communicable in the frequency band. The same operation and effect can be obtained.
[0089]
4 to 9 is not limited to the determination as to whether or not a wireless channel can be allocated to each scheme system. For each of a plurality of frequency bands in each scheme system, a mobile station that can communicate in the frequency band is determined. On the other hand, the present invention can be applied to the case of allocating a wireless line, and similar operations and effects can be obtained.
[0090]
【The invention's effect】
As described above, according to the present invention, in each system, in order to determine whether or not a line can be allocated to a shared mobile station in accordance with the line usage rate in the wireless zone or the call blocking rate, the line usage of the shared mobile station is determined. As a result, it is possible to prevent a line in which the dedicated mobile station can be used from being squeezed, thereby preventing the call loss rate of the dedicated mobile station from increasing compared to the call loss rate of the shared mobile station.
[0091]
Further, in the system of the final candidate which attempts to allocate a wireless line to the shared mobile station, a vacant wireless line is allocated in the same manner as the dedicated mobile station. As much as possible connection quality can be provided to users using mobile stations and users using shared mobile stations.
[0092]
In addition, the present invention not only controls allocation of a radio channel to a mobile station for performing communication based on each of a plurality of system systems, but also performs communication in each of a plurality of frequency bands in one system system in the frequency band. The present invention can also be applied when assigning a radio line to a possible mobile station.
[0093]
Further, the present invention is not limited to the determination as to whether or not a wireless channel can be allocated to each scheme system. For each of a plurality of frequency bands in each scheme system, when assigning a wireless channel to a mobile station that can communicate in the frequency band. Can also be applied to the determination of the assignment availability. As described above, the present invention can be said to be a highly versatile and effective technology.
[Brief description of the drawings]
FIG. 1 is a configuration diagram of a multiple system sharing system according to an embodiment of the present invention.
FIG. 2 is a configuration diagram of a radio network controller.
FIG. 3 is a diagram illustrating a first example of a process related to wireless channel assignment.
FIG. 4 is a flowchart illustrating a first example of an assignment availability determination process;
FIG. 5 is a flowchart showing a second example of the assignment availability determination processing.
FIG. 6 is a flowchart showing a third example of the assignment availability determination processing.
FIG. 7 is a flowchart showing a fourth example of the assignment availability determination processing.
FIG. 8 is a flowchart showing a fifth example of the assignment availability determination processing.
FIG. 9 is a flowchart showing a sixth example of the assignment availability determination processing.
FIG. 10
FIG. 9 is a diagram illustrating a second example of a process related to wireless channel assignment.
FIG. 11
FIG. 14 is a diagram illustrating a third example of a process related to wireless channel assignment.
[Explanation of symbols]
100: Multiple system sharing system, 101: Core network, 102, 107: Radio network controller, 103, 108: Radio base station, 104, 109: Radio zone, 105, 110: Dedicated mobile station, 106: Shared mobile station, 201, 202: transmission / reception unit, 203: control unit, 204: information storage unit.

Claims

A control device for each of the system systems that controls radio channel allocation for performing communication based on each of the plurality of system systems; a shared mobile station that can perform communication based on each of the plurality of system systems; In a multiple system shared system configured to include a dedicated mobile station for each system capable of performing only communication based on the system of the above, when each control device allocates a radio line to the shared mobile station, A wireless line allocation control method,
Each controller is
If the assignment of a wireless channel to the shared mobile station is requested and the own device is not the final candidate control device that attempts to assign the wireless channel, it is determined whether or not the wireless channel can be assigned based on predetermined conditions, and based on the determination result, To control the assignment of wireless lines,
When requested to allocate a wireless channel to the shared mobile station and the own device is the final candidate control device that attempts to allocate the wireless channel, avoiding the determination of wireless channel allocation availability and avoiding wireless channel allocation to the shared mobile station. Make an assignment,
A wireless channel assignment control method characterized by the above-mentioned.

The wireless channel assignment request includes information on a communicable system of the shared mobile station,
Each control device determines, based on the communicable system information of the shared mobile station, whether or not the own device is a final candidate control device that attempts to allocate a wireless channel.
Radio channel allocation control method according to claim 1, wherein a.

The shared mobile station outputs an assignment request including information on a communicable system of the shared mobile station,
One control device that has received the assignment request,
Determine whether wireless lines can be assigned based on predetermined conditions,
If the determination result indicates that allocation is impossible, it is determined whether or not the other candidate control device is the final candidate control device that attempts to allocate a radio channel based on the system information on the communicable system of the shared mobile station. And
Adding the determination information of the final candidate to the allocation request, and outputting the information to the other candidate control device,
Radio channel allocation control method according to claim 1, wherein a.

One control device that has received the wireless line assignment request,
Determine whether wireless lines can be assigned based on predetermined conditions,
If the determination result is unassignable, notify the shared mobile station of the determination result,
The shared mobile station is
Based on system information capable of communicating with the own station, it is determined whether or not the other candidate control device is the final candidate control device that attempts to allocate a radio line,
Adding the determination information of the final candidate to the allocation request, and outputting the information to the other candidate control device,
Radio channel allocation control method according to claim 1, wherein a.

Each control device determines whether or not the wireless line can be assigned,
Comparing the line usage rate of all mobile stations representing the ratio of the number of wireless lines used by all mobile stations to the total number of wireless lines in the wireless zone under the control of the own device with a first threshold value,
When the line usage rate of all the mobile stations is lower than the first threshold, it is determined that the mobile station can be assigned,
If the line usage rate of all mobile stations is equal to or greater than the first threshold, it is determined that assignment is impossible.
The method according to any one of claims 1 to 4 , wherein:

Each control device determines whether or not the wireless line can be assigned,
Comparing the line usage rate of the shared mobile station, which represents the ratio of the number of wireless links used by the shared mobile station to the total number of wireless links in the wireless zone under the control of the own apparatus, with a second threshold value;
When the line usage rate of the shared mobile station is lower than the second threshold value, it is determined that assignment is possible,
When the line usage rate of the shared mobile station is equal to or more than the second threshold, it is determined that assignment is impossible.
The method according to any one of claims 1 to 4 , wherein:

Each control device determines whether or not the wireless line can be assigned,
The line usage rate of all mobile stations, which represents the ratio of the number of radio lines in use by all mobile stations to the total number of radio lines in the radio zone under the control of the own device, is compared with a first threshold value. Comparing the line usage rate of the shared mobile station, which represents the ratio of the number of wireless lines used by the shared mobile station to the number of lines, with a second threshold value;
When the line usage rate of all mobile stations is lower than the first threshold value and the line usage rate of the shared mobile station is lower than the second threshold value, it is determined that allocation is possible,
If the line usage rate of all mobile stations is equal to or higher than the first threshold or the line usage rate of the shared mobile station is equal to or higher than the second threshold, it is determined that assignment is impossible.
The method according to any one of claims 1 to 4 , wherein:

Each control device determines whether or not the wireless line can be assigned,
The line usage rate of all mobile stations, which represents the ratio of the number of radio lines in use by all mobile stations to the total number of radio lines in the radio zone under the control of the own device, is compared with a first threshold value. Comparing the line usage rate of the shared mobile station, which represents the ratio of the number of wireless lines used by the shared mobile station to the number of lines, with a second threshold value;
If the line usage rate of all mobile stations is lower than the first threshold value or the line usage rate of the shared mobile station is lower than the second threshold value, it is determined that assignment is possible;
If the line usage rate of all mobile stations is equal to or higher than the first threshold and the line usage rate of the shared mobile station is equal to or higher than the second threshold, it is determined that assignment is impossible.
The method according to any one of claims 1 to 4 , wherein:

Each control device determines whether or not the wireless line can be assigned,
The loss probability of the dedicated mobile station, which represents the ratio of the number of failures in allocating a wireless channel to a dedicated mobile station to the number of wireless channel allocation requests from the dedicated mobile station within a fixed time within a wireless zone under the control of the own device, is expressed by a third Compared to the threshold of
When the call blocking rate of the dedicated mobile station is lower than the third threshold, it is determined that the dedicated mobile station can be assigned,
When the call loss rate of the dedicated mobile station is equal to or more than the third threshold value, it is determined that assignment is impossible.
The method according to any one of claims 1 to 4 , wherein:

Each control device determines whether or not the wireless line can be assigned,
The loss probability of the dedicated mobile station, which represents the ratio of the number of failed wireless channel assignments to the dedicated mobile station to the number of wireless channel assignment requests from the dedicated mobile station within a fixed time within the wireless zone under the control of the own device, Compared with the call loss rate of the shared mobile station, which represents the ratio of the number of wireless channel allocation failures to the shared mobile station to the number of wireless channel allocation requests from the shared mobile station within a certain time in the zone,
If the call loss rate of the dedicated mobile station is equal to or less than the call loss rate of the shared mobile station, it is determined that assignment is possible,
If the call loss rate of the dedicated mobile station is higher than the call loss rate of the shared mobile station, it is determined that assignment is impossible,
The method according to any one of claims 1 to 4 , wherein:

For each of a plurality of frequency bands in one system, communication is performed with a control device for each frequency band that performs radio channel allocation control for allocating a radio channel to a mobile station capable of communicating in the frequency band, in a plurality of frequency bands In a mobile communication system including a possible shared mobile station and a dedicated mobile station for each frequency band that can communicate only in one frequency band, each control device allocates a radio channel to the shared mobile station. Wireless line allocation control method,
Each controller is
If the assignment of a wireless channel to the shared mobile station is requested and the own device is not the final candidate control device that attempts to assign the wireless channel, it is determined whether or not the wireless channel can be assigned based on predetermined conditions, and based on the determination result, To control the assignment of wireless lines,
When requested to allocate a wireless channel to the shared mobile station and the own device is the final candidate control device that attempts to allocate the wireless channel, avoiding the determination of wireless channel allocation availability and avoiding wireless channel allocation to the shared mobile station. Make an assignment,
A wireless channel assignment control method characterized by the above-mentioned.

The request to allocate a wireless line includes information on a frequency band in which the shared mobile station can communicate,
Each control device determines, based on the communicable frequency band information of the shared mobile station, whether or not the own device is a final candidate control device that attempts to allocate a wireless channel.
The method according to claim 11, wherein:

The shared mobile station outputs an allocation request including information on a communicable frequency band of the shared mobile station,
One control device that has received the assignment request,
Determine whether wireless lines can be assigned based on predetermined conditions,
If the determination result indicates that allocation is impossible, it is determined whether or not another candidate control device is a final candidate control device that attempts to allocate a radio channel based on the communicable frequency band information of the shared mobile station. And
Adding the determination information of the final candidate to the allocation request, and outputting the information to the other candidate control device,
The method according to claim 11, wherein:

One control device that has received the wireless line assignment request,
Determine whether wireless lines can be assigned based on predetermined conditions,
If the determination result is unassignable, notify the shared mobile station of the determination result,
The shared mobile station is
Based on the communicable frequency band information of the own station, it is determined whether or not the other candidate control device is the final candidate control device that attempts to allocate a radio line,
Adding the determination information of the final candidate to the allocation request, and outputting the information to the other candidate control device,
The method according to claim 11, wherein:

The control device is configured to determine whether or not the wireless line can be assigned,
A line usage rate of all mobile stations, which represents a ratio of the number of wireless lines used by all mobile stations to the total number of wireless lines in the frequency band controlled by the own device, is compared with a first threshold value,
When the line usage rate of all the mobile stations is lower than the first threshold, it is determined that the mobile station can be assigned,
If the line usage rate of all mobile stations is equal to or greater than the first threshold, it is determined that assignment is impossible.
The wireless channel allocation control method according to claim 11 , wherein:

The control device is configured to determine whether or not the wireless line can be assigned,
Comparing the line usage rate of the shared mobile station, which represents the ratio of the number of wireless links used by the shared mobile station to the total number of wireless links in the frequency band controlled by the own apparatus, with a second threshold value;
When the line usage rate of the shared mobile station is lower than the second threshold value, it is determined that assignment is possible,
When the line usage rate of the shared mobile station is equal to or more than the second threshold, it is determined that assignment is impossible.
The wireless channel allocation control method according to claim 11 , wherein:

The control device is configured to determine whether or not the wireless line can be assigned,
The line usage ratio of all mobile stations, which represents the ratio of the number of wireless lines used by all mobile stations to the total number of wireless lines in the frequency band controlled by the own device, is compared with a first threshold value. Comparing the line usage rate of the shared mobile station, which represents a ratio of the number of wireless lines used by the shared mobile station to the number of lines, with a second threshold value,
When the line usage rate of all mobile stations is lower than the first threshold value and the line usage rate of the shared mobile station is lower than the second threshold value, it is determined that allocation is possible,
If the line usage rate of all mobile stations is equal to or higher than the first threshold or the line usage rate of the shared mobile station is equal to or higher than the second threshold, it is determined that assignment is impossible.
The wireless channel allocation control method according to claim 11 , wherein:

The control device is configured to determine whether or not the wireless line can be assigned,
The line usage ratio of all mobile stations, which represents the ratio of the number of wireless lines used by all mobile stations to the total number of wireless lines in the frequency band controlled by the own device, is compared with a first threshold value. Comparing the line usage rate of the shared mobile station, which represents a ratio of the number of wireless lines used by the shared mobile station to the number of lines, with a second threshold value,
If the line usage rate of all mobile stations is lower than the first threshold value or the line usage rate of the shared mobile station is lower than the second threshold value, it is determined that assignment is possible;
If the line usage rate of all mobile stations is equal to or higher than the first threshold and the line usage rate of the shared mobile station is equal to or higher than the second threshold, it is determined that assignment is impossible.
The wireless channel allocation control method according to claim 11 , wherein:

The control device is configured to determine whether or not the wireless line can be assigned,
A third specific mobile station call loss rate, which represents the ratio of the number of failures in allocating a wireless channel to a dedicated mobile station to the number of wireless channel allocation requests from the dedicated mobile station within a fixed time in a frequency band controlled by the own device, Compare with the threshold,
When the call blocking rate of the dedicated mobile station is lower than the third threshold, it is determined that the dedicated mobile station can be assigned,
When the call loss rate of the dedicated mobile station is equal to or more than the third threshold value, it is determined that assignment is impossible.
The wireless channel allocation control method according to claim 11 , wherein:

The control device is configured to determine whether or not the wireless line can be assigned,
The blocking rate of the dedicated mobile station, which represents the ratio of the number of failed wireless channel assignments to the dedicated mobile station with respect to the number of wireless channel assignment requests from the dedicated mobile station within a fixed time in the frequency band controlled by the own apparatus, In comparison with the call loss rate of the shared mobile station, which represents the ratio of the number of failed wireless channel assignments to the shared mobile station with respect to the number of wireless line assignment requests from the shared mobile station within a certain period of time,
If the call loss rate of the dedicated mobile station is equal to or less than the call loss rate of the shared mobile station, it is determined that assignment is possible,
If the call loss rate of the dedicated mobile station is higher than the call loss rate of the shared mobile station, it is determined that assignment is impossible,
The wireless channel allocation control method according to claim 11 , wherein:

A control device for each of the system systems that controls radio channel allocation for performing communication based on each of the plurality of system systems; a shared mobile station that can perform communication based on each of the plurality of system systems; A multi-system shared system including a dedicated mobile station for each system capable of performing only communication based on the system,
Each controller is
Receiving means for receiving from the shared mobile station a request to allocate a wireless channel to the shared mobile station,
Assignment availability determination means for determining availability of wireless lines based on predetermined conditions,
Allocating means for allocating a radio line to the shared mobile station,
When receiving the request for allocating a wireless channel to the shared mobile station and if the own device is not the final candidate control device that attempts to allocate the wireless channel, the allocation determining unit determines whether or not the wireless channel can be allocated, and the allocating unit determines Control to allocate a wireless line based on the determination result, receiving a request to allocate a wireless line to the shared mobile station, and if the device itself is a final candidate control device to try to allocate a wireless line, the allocation Control means for controlling whether or not the wireless line can be assigned by the availability determination means, and controlling the assignment of the wireless line by the assignment means;
A multi-system sharing system comprising:

The wireless channel assignment request includes information on a communicable system of the shared mobile station,
Each controller is
Further comprising a first final candidate determining means for determining whether or not the own device is a final candidate control device that attempts to allocate a wireless channel based on the communicable system information of the shared mobile station.
22. The multiple system sharing system according to claim 21, wherein:

The shared mobile station outputs an assignment request including information on a communicable system of the shared mobile station,
The control device,
If it is determined that the allocation is not possible by the allocation permission / non-permission determination unit, the control device serving as another candidate is a control device of a final candidate that attempts to allocate a radio channel based on information on a communicable system of the shared mobile station. Second final candidate determining means for determining whether or not
Request output means for adding the determination information of the final candidate to the allocation request, and outputting the information to another candidate control device;
22. The multiple system sharing system according to claim 21 , further comprising:

The control device,
When it is determined that the allocation is not possible by the allocation permission / non-permission determination unit, the mobile terminal further includes a notification unit that notifies the shared mobile station of the determination result,
The shared mobile station,
Candidate determination means for determining whether or not the other candidate control device is a final candidate control device that attempts to allocate a wireless channel, based on system information capable of communicating with the own station,
Output means for adding the determination information of the final candidate to the allocation request, and outputting the information to another candidate control device.
22. The multiple system sharing system according to claim 21, wherein:

A multi-system shared system is configured with a shared mobile station capable of performing communication based on each of the plurality of system systems and a dedicated mobile station for each system capable of performing communication based on only one system. A control device that performs wireless channel allocation control for performing communication based on a predetermined one of the plurality of system systems,
Receiving means for receiving from the shared mobile station a request to allocate a wireless channel to the shared mobile station,
Assignment availability determination means for determining availability of wireless lines based on predetermined conditions,
Allocating means for allocating a radio line to the shared mobile station,
When receiving the request for allocating a wireless channel to the shared mobile station and if the own device is not the final candidate control device that attempts to allocate the wireless channel, the allocation determining unit determines whether or not the wireless channel can be allocated, and the allocating unit determines Control to allocate a wireless line based on the determination result, receiving a request to allocate a wireless line to the shared mobile station, and if the device itself is a final candidate control device to try to allocate a wireless line, the allocation Control means for controlling whether or not the wireless line can be assigned by the availability determination means, and controlling the assignment of the wireless line by the assignment means;
The control device provided with.