JP3851505B2 - FH communication signal analyzing apparatus and FH communication signal analyzing method - Google Patents

Description

【００２７】
ただし、Ｔｓは、ＦＨ通信の開始時刻を示す。また、各ＦＨ通信を最初から観測できるとは限らないので、その開始時刻を知ることが困難な場合がある。この場合、ある時刻Ｔｓ’を規準として、この後、ｉ’番目にトーン周波数を変更する時刻は次式で表される。
【００２８】
【数２】

【００２９】
ただし、整数Ｎは、ｉ’＝０の場合に、上式の右辺が時刻Ｔｓ’よりも過去となる最大の整数である。また、φは、Ｔｃをトーン周波数を変更した時刻の１つとして、φ＝mod（Ｔｃ，Ｔｈ）として求めることができる。ここではφを位相と呼ぶ。
【００３０】
実施の形態１．
まず、本発明の実施の形態１を説明する。図１に本実施の形態１におけるＦＨ通信信号分析装置のブロック図を示す。図において、１０−１，１０−２，…，１０−Ｎは、予め設定された周波数の信号のみを通過させるＢＰＦ、１１は、検波を行うタイミングを設定し、後述する検波手段を制御する検波タイミング発生手段、１２−１，１２−２，…，１２−Ｎは、検波タイミング発生手段１１が制御する時刻に、各ＢＰＦ１０−１，１０−２，…，１０−Ｎの出力信号の強度を計測する検波手段、２０は、これまでの各ＢＰＦの出力信号強度の系列と、これまでに推定したトーン周波数の系列から、ホッピング速度などのＦＨ通信の特徴を推定するＦＨ特徴推定手段、２１は、ＦＨ特徴と各ＢＰＦの出力信号強度から、ＦＨ通信が現在用いている周波数を推定するトーン推定手段である。
【００３１】
以下、図２に示すフローチャートに沿って、図１に示すＦＨ通信信号分析装置の動作を説明する。
【００３２】
ＢＰＦ１０―１〜１０―Ｎ、検波タイミング発生手段１１、検波手段１２―１〜１２―Ｎは、従来と同様の働きをする。（ステップＳＴ１０、ＳＴ１１、ＳＴ１２）。
【００３３】
次に、ＦＨ特徴推定手段２０は、各検波手段１２―１〜１２―Ｎが出力する各ＢＰＦの出力信号強度とトーン推定手段２１が出力するトーン周波数を入力として、まず、これらを蓄積する。そして、蓄積された各ＢＰＦの出力信号強度の系列と、蓄積されたトーン周波数の系列から、ＦＨ特徴としてＦＨ通信のホッピング速度Ｔｈ、もしくは、ホッピング速度Ｔｈと位相φを推定し、これをトーン推定手段２１に出力する（ステップＳＴ２０）。
【００３４】
例えば、トーン周波数の系列から、トーン周波数を変更した回数を求めることができる。そして、このＦＨ通信を観測している時間を、この回数で割れば、ホッピング速度Ｔｈを推定できる。
また、ある時刻に推定したトーン周波数と、次の時刻で推定したトーン周波数が異なっていれば、この時間内にトーン周波数を変更したと考えられる。よって、トーン周波数を変更した時刻範囲の系列を求めることができる。
上記の式（１）もしくは式（２）に推定されたホッピング速度Ｔｈを与え、さらに、０以上Ｔｈ以下の任意の値をφに代入して、位相φがその値である場合に、トーン周波数を変更する時刻Ｔｉ（もしくはＴｉ’）の系列を求める。これらの時刻が先に求めたトーン周波数を変更した時刻範囲の系列に含まれるか否かを判定し、含まれる数Nｔを求める。そして、φを変更することにより、Nｔが最大となるφを求める。ただし、含まれる数Nｔが同数となるφが複数存在すると考えられるので、この場合、その範囲を求め、例えば、その中心値をφとする。
【００３５】
トーン推定手段２１では、まず、ＦＨ特徴推定手段２０から入力されたＦＨ特徴から、トーン周波数を変更する時刻の系列を求める。次に、先にトーン周波数を推定した時刻から現在までにトーン周波数を変更する時刻を通過したか否かを求める。最後に、通過していなければ先と同じトーン周波数を出力し、通過していれば、各ＢＰＦの出力信号強度を比較し、最も強度が強いＢＰＦの周波数をトーン周波数として出力する（ステップＳＴ２１）。
【００３６】
以上のように、本実施の形態においては、トーン周波数の変更時刻を考慮することによって、トーン周波数を変更する時刻前でトーン周波数が変更されていないにも関わらず、誤ってノイズを検出してトーン周波数が変更されたと推定する危険性をなくすことができ、高い推定精度を得ることができる。
【００３７】
実施の形態２．
次に、本発明の実施の形態２を説明する。図３に本実施の形態２におけるＦＨ通信信号分析装置のブロック図を示す。図において、３０は、ＦＨ通信が用いた周波数の系列に関して複数の候補を考え、これらの候補を仮説として生成する仮説生成手段、３１は、これまでの各ＢＰＦの出力信号強度の系列と、仮説生成手段３０により生成された各仮説における周波数の系列の候補とから、各仮説においてホッピング速度などのＦＨ通信の特徴を推定し、その仮説の評価値を求めるＦＨ特徴更新手段、３２は、入力された複数の仮説の中から、それぞれの仮説の評価値を指標としていくつかの仮説を選択し、その他の仮説を除去する仮説除去手段、３３は、入力された複数の仮説からＦＨ通信が現在用いている周波数を推定する仮説選択手段である。他の構成については、実施の形態１で示したものと同一であるため、同一符号を付して示し、説明を省略する。
【００３８】
以下、図４に示すフローチャートに沿って、図３に示すＦＨ通信信号分析装置の動作を説明する。なお、検波を行った時刻をｔ↓ｉ（1≦ｉ≦Nm）とする。この装置では、ＦＨ通信に関して、各時刻におけるＦＨ通信のトーン周波数ｆ（ｔ↓ｉ ）の系列｛ｆ｝＝｛ｆ（ｔ↓１），ｆ（ｔ↓２），…，ｆ（ｔ↓Ｎｍ）｝、および、その信号強度ｐ（ｔ↓ｉ）の系列｛ｐ｝＝｛ｐ（ｔ↓１），ｐ（ｔ↓２），…，ｐ（ｔ↓Ｎｍ）｝、および、ＦＨ特徴Ｔｈ、φを求める。そのため、これらに何らかの値を仮定すると、解の候補となる。この解の候補を仮説と呼ぶ。
【００３９】
ＢＰＦ１０−１〜１０−Ｎ、検波タイミング発生手段１１、検波手段１２−１〜１２−Ｎは、実施の形態１と同様の働きをする。（ステップＳＴ１０、ＳＴ１１、ＳＴ１２）。
【００４０】
仮説生成手段３０は、仮説除去手段３２からフィードバックされる仮説、および、各検波手段が出力するＢＰＦの出力信号強度を入力とする。まず、各検波手段が出力するＢＰＦの出力信号強度から、レーダにおける目標検出手法などを用いて、ＦＨ通信信号が含まれると考えるＢＰＦを選択する。このような検出手法を用いた場合、複数のＢＰＦが選択されたり、一つもＢＰＦが選択されない場合がある。一つも選択されなかった場合は、各ＢＰＦの出力信号強度のうち、最も強いものを探し、その信号を出力しているＢＰＦを選択する。
【００４１】
次に、仮説除去手段３２から仮説が入力されていない場合には、選択されたＢＰＦそれぞれにおいて、そのＢＰＦの周波数が現在のトーン周波数であり、選択されたＢＰＦの信号強度がそのトーン周波数の信号強度であるとする仮説を生成する。よって、仮説は、選択したＢＰＦの数だけ生成される。
例えば、選択されたＢＰＦが２つで、その周波数がｆ１、ｆ２で、信号強度がｐ１，ｐ２である場合、トーン周波数の系列が｛ｆ｝＝｛ｆ１｝，受信強度の系列が｛ｐ｝＝｛ｐ１｝で、ＦＨ特徴が不明の仮説と、トーン周波数の系列が｛ｆ｝＝｛ｆ２｝，受信強度の系列が｛ｐ｝＝｛ｐ２｝で、ＦＨ特徴が不明の仮説の合計２つの仮説が生成される。
【００４２】
また、仮説除去手段３２から仮説が入力された場合には、各仮説に対して、選択されたＢＰＦのいずれかの周波数が現在のトーン周波数であり、そのＢＰＦの信号強度がそのトーン周波数の信号強度であるということを追加し、それぞれを仮説とする。よって、入力された仮説がNｉ個、選択されたＢＰＦがN ｆ個あると、合計Nｉ×Nｆ個の、現在のトーン周波数までを記した新たな仮説が生成される。
例えば、選択されたＢＰＦが２つで、その周波数がｆ１、ｆ２、信号強度がｐ１，ｐ２である場合に、トーン周波数の系列が｛ｆ｝↓１、その信号強度の系列が｛ｐ｝↓１、ＦＨ特徴Ｔｈ↓１、φ↓１である仮説に対して、上記の処理を行うと、トーン周波数の系列が｛｛ｆ｝↓１、ｆ１｝、その信号強度の系列が｛｛ｐ｝↓１、ｐ１｝、ＦＨ特徴Ｔｈ↓１、φ↓１である仮説と、トーン周波数の系列が｛｛ｆ｝↓１、ｆ２｝、その信号強度の系列が｛｛ｐ｝↓１、ｐ２｝、ＦＨ特徴Ｔｈ↓１、φ↓１である仮説の合計２つの仮説が生成される。
【００４３】
このように仮説を生成した後、最後に、これらの仮説をＦＨ特徴更新手段３１に出力する（ステップＳＴ３０）。
【００４４】
ＦＨ特徴更新手段３１は、仮説生成手段から１つ以上の仮説を入力される。まず、入力された各仮説において、実施の形態１における特徴推定手段と同様にして、ＦＨ特徴を求める。
次に、各仮説について、その評価値を求め、これを各仮説に付加する。例えば、位相φを求める際に求めたNtや、仮説に記された信号強度の系列｛ｐ｝に含まれる信号強度ｐ（ｔ↓ｉ）の総和Σを評価値としたり、Nｔ×Σを評価値とすることなどが考えられる。
最後に、ＦＨ特徴を求め、評価値を付加した仮説を出力する（ステップＳＴ３１）。
【００４５】
仮説除去手段３２では、ＦＨ特徴推定手段３１から出力される１つ以上の仮説を入力として、これらの仮説に付加された評価値を比較し、評価値の良い仮説をいくつか選択して、これらを出力し、その他の仮説を除去する（ステップＳＴ３２）。
この選択の仕方としては、事前に決めておいた数だけの仮説を、評価値の良い順に選択する方法や、ある事前に決められた評価値より良い評価値が付加されている仮説のみを選択する方法などが考えられる。
【００４６】
仮説選択手段３３では、仮説除去手段３２が出力する仮説を入力として、これらの仮説から、トーン周波数を推定して出力する（ステップＳＴ３３）。
このトーン周波数の推定方法としては、付加された評価値が最も良い仮説を選択し、この仮説における現在のトーン周波数を、本装置が推定した現在のトーン周波数とする方法や、各仮説における現在のトーン周波数を調べ、最も多くの仮説でトーン周波数であるとされていた周波数を、本装置が推定した現在のトーン周波数とする方法などが考えられる。
【００４７】
以上のように、本実施の形態においては、複数の仮説を生成し、かつ、保持しながら、トーン周波数を推定していくので、いったん、誤った仮説の評価値が良くなり、誤ったトーン周波数やＦＨ特徴が推定されても、後の観測結果から正しい仮説の評価値が良くなるため、その誤りを修正できる。よって、より正しいトーン周波数の推定が可能となる。
【００４８】
実施の形態３．
次に、本発明の実施の形態３を説明する。図５に本実施の形態３にかかるＦＨ通信信号分析装置のブロック図を示す。図において、３５は、複数のＦＨ通信が存在することを考慮し、ＦＨ通信の数や、各ＦＨ通信が用いた周波数の系列に関して複数の候補を考え、これらの候補を仮説として生成する複数目標仮説生成手段、３６は、これまでの各ＢＰＦの出力信号強度の系列と、複数目標仮説生成手段３５により生成された各仮説における周波数の系列の候補とから、各仮説において各ＦＨ通信のホッピング速度などのＦＨ通信の特徴を推定し、その仮説の評価値を求める複数目標のＦＨ特徴更新手段である。なお、他の構成については、実施の形態１及び実施の形態２で示したものと同一であるため、同一符号を付して示し、説明を省略する。
【００４９】
ここでは、複数のＦＨ通信が同時に行われる可能性があるものとして、ＦＨ通信の数Ｎｃ、および、検波を行った各時刻ｔ↓ｉ（1≦ｉ≦Nｍ）における、それぞれのＦＨ通信ｊ（１≦ｊ≦Nｃ）のトーン周波数ｆ↓ｊ（ｔ↓ｉ）の系列｛ｆ↓ｊ｝、および、その信号強度ｐ↓ｊ（ｔ↓ｉ）の系列｛ｐ↓ｊ｝、および、それぞれのＦＨ通信のＦＨ特徴Ｔｈ↓ｊ、φ↓ｊについてある値を仮定した解の候補を仮説と呼ぶ。
【００５０】
以下、図６に示すフローチャートに沿って、図５に示すＦＨ通信信号分析装置の動作を説明する。
【００５１】
ＢＰＦ１０―１〜１０―Ｎ、検波タイミング発生手段１１、検波手段１２−１〜１２―Ｎ、仮説除去手段３２、仮説選択手段３３は、実施の形態２と同様の働きをする。（ステップＳＴ１０、ＳＴ１１、ＳＴ１２、ＳＴ３２、ＳＴ３３）。
【００５２】
複数目標仮説生成手段３５は、仮説除去手段３２からフィードバックされる仮説、および、各検波手段が出力する各ＢＰＦの出力信号強度を入力とする。まずは、実施の形態２における仮説生成手段と同様にして、通信信号が含まれる信号を出力していると考えられるＢＰＦを１つ以上選択する。
【００５３】
次に、仮説除去手段３２から仮説が入力されていない場合には、選択されたＢＰＦの周波数の数がNｆであれば、それぞれのＢＰＦの出力信号が、あるＦＨ通信のトーン周波数の信号であるか、ノイズを誤って検出したものであるかとして全ての組合せを考え、２のNf乗個の仮説を生成する。
【００５４】
例えば、選択されたＢＰＦが２つで、その周波数がｆ１、ｆ２、その信号強度がｐ１，ｐ２である場合、ＦＨ通信数Ｎｃが２で、１つめのＦＨ通信のトーン周波数の系列が｛ｆ｝＝｛ｆ１｝，受信強度の系列が｛ｐ｝＝｛ｐ１｝であり、２つめのＦＨ通信のトーン周波数の系列が｛ｆ｝＝｛ｆ２｝，受信強度の系列が｛ｐ｝＝｛ｐ２｝であり、それぞれのＦＨ特徴が不明の仮説と、ＦＨ通信数Ｎｃが１で、トーン周波数の系列が｛ｆ｝＝｛ｆ１｝， 受信強度の系列が｛ｐ｝＝｛ｐ１｝であり、ＦＨ特徴が不明の仮説と、ＦＨ通信数Ｎｃが１で、トーン周波数の系列が｛ｆ｝＝｛ｆ２｝，受信強度の系列が｛ｐ｝＝｛ｐ２｝であり、ＦＨ特徴が不明の仮説と、ＦＨ通信数Ｎｃが０である仮説の併せて４（＝２の２乗）個の仮説が生成される。
【００５５】
また、仮説除去手段３２から、Nｉ個の仮説が入力された場合には、それぞれの仮説に対して以下の処理を行い、複数の仮説を生成する。各仮説で仮定されているＦＨ通信のトーン周波数が、選択されたＢＰＦのいずれかの周波数であるか、もしくは、このＦＨ通信はすでに通信を終了したかとして、全ての場合を考え、さらに、各場合において、これまでのどのＦＨ通信のトーン周波数でもないとされたＢＰＦの周波数は、ノイズを誤って検出したものか、もしくは、新規ＦＨ通信のトーン周波数であるとして、各場合から、さらに詳細な組合せを考える。そして、各組合せにおいて仮定している各ＦＨ通信のトーン周波数とその信号強度を、元の仮説に追加し、それぞれを仮説として生成する。
【００５６】
選択されたＢＰＦが２つで、その周波数がｆ１、ｆ２であり、その信号強度がｐ１, ｐ２である場合に、ＦＨ通信数Nｃが１であり、そのトーン周波数の系列が｛ｆ｝↓１、その信号強度の系列が｛ｐ｝↓１、ＦＨ特徴Ｔｈ↓１、φ↓１である仮説に対して、上記の処理を行う例を説明する。
【００５７】
まず、この仮説で仮定されているＦＨ通信Cの現在のトーン周波数が、ｆ１である場合と、ｆ２である場合と、ＦＨ通信Ｃがすでに終了している場合の３通りの場合が考えられる。
次に、このＦＨ通信Cのトーン周波数がｆ１である場合には、ＦＨ通信Ｃのトーン周波数でないとされたｆ２は、新規ＦＨ通信のトーン周波数か、ノイズを誤って検出したものであるので、ＦＨ通信数Nｃが２であり、１つめのＦＨ通信のトーン周波数の系列が｛｛ｆ｝↓１、ｆ１｝、その信号強度の系列が｛｛ｐ｝↓１、ｐ１｝、ＦＨ特徴Ｔｈ↓１、φ↓１であり、２つめのＦＨ通信のトーン周波数の系列が{ｆ２}、その信号強度の系列が{ｐ２}、ＦＨ特徴が未知である仮説と、ＦＨ通信数Nｃが１であり、ＦＨ通信のトーン周波数の系列が｛｛ｆ｝↓１、ｆ１｝、その信号強度の系列が｛｛ｐ｝↓１、p1 ｝、ＦＨ特徴Ｔｈ↓１、φ↓１である仮説の２つの仮説が生成される。
また、上記のＦＨ通信Cのトーン周波数がf2である場合には、ｆ１は新規ＦＨ通信のトーン周波数か、ノイズを誤って検出したものであるので、同様に２つの仮説が生成される。さらに、このＦＨ通信Ｃが終了している場合には、ｆ１，ｆ２はそれぞれ新規ＦＨ通信のトーン周波数か、ノイズを検出したものであるので、２×２通りの組合せが考えられ、４つの仮説が生成される。よって、合計８つの仮説が生成される。
【００５８】
このようにして仮説を生成した後、最後に、これらの仮説を複数目標のＦＨ特徴更新手段３６に出力する（ステップＳＴ３５）。
【００５９】
複数目標のＦＨ特徴更新手段３６は、実施の形態２におけるＦＨ特徴更新手段と同様に、ＦＨ特徴を求める。ただし、これらの仮説では、複数のＦＨ通信が存在する場合があるので、この場合は、各ＦＨ通信毎に、ＦＨ特徴を求める。
次に、各仮説において、その評価値を求める。この際、複数のＦＨ通信を仮定している場合があるので、この場合、それぞれのＦＨ通信に関して、実施の形態２と同様に評価値を算出して、その総和や平均値を仮説の評価値とする。
最後に、ＦＨ特徴を求め、評価値を付加した仮説を出力する（ステップＳＴ３６）。
【００６０】
以上のように、本実施の形態においては、複数のＦＨ通信が存在することを考慮して仮説を生成し、それぞれのＦＨ通信のトーン周波数を求めるので、各ＦＨ通信のトーン周波数の系列を正しく求めることができる。さらにこのため、特定のＦＨ通信だけ妨害を行うことができる。
【００６１】
実施の形態４．
次に、本発明の実施の形態４を説明する。図７に本実施の形態４にかかるＦＨ通信信号分析装置のブロック図を示す。図において、４０は、ＦＨ特徴を入力として、最も現在から近くで、ＦＨ通信が周波数を変更する時刻を推定し、この時刻の直後に検波を行うように、検波タイミングを制御する検波タイミング制御手段である。なお、他の構成については、実施の形態１で示したものと同一であるため、同一符号を付して示し、説明を省略する。
【００６２】
以下、図８に示すフローチャートに沿って、図７に示すＦＨ通信信号分析装置の動作を説明する。
【００６３】
ＢＰＦ１０−１〜１０−Ｎ、検波手段１２−１〜１２−Ｎ、トーン推定手段２１は、実施の形態１と同様の働きをする（ステップＳＴ１０、ＳＴ１２、ＳＴ２１）。
【００６４】
ＦＨ特徴推定手段２０は、実施の形態１と同様の働きをする。ただし、検波タイミング制御手段にもＦＨ特徴を出力する（ステップＳＴ２０）。また、検波タイミング制御手段にＦＨ特徴を推定するのは、実施の形態２で示したＦＨ特徴更新手段３１や実施の形態３で示した複数目標のＦＨ特徴更新手段３６でも良い。ただし、ＦＨ特徴更新手段３１や複数目標のＦＨ特徴更新手段３６の場合、複数の仮説において異なるＦＨ特徴が記されたり、各仮説において複数のＦＨ通信が仮定されて複数のＦＨ特徴が記されているので、これら全てのＦＨ特徴を出力する。
【００６５】
検波タイミング制御手段４０は、ＦＨ特徴を入力として、上述した式（１）や式（２）を用いて、現在から最も近い時刻で、トーン周波数が変更される時刻を予測する。ただし、複数のＦＨ特徴が入力された場合は、それぞれで式（１）や式（２）を用いて、最も近い時刻でトーン周波数が変更される時刻を予測し、さらに、それらの時刻の中で最も近い時刻を求める。そして、求められた時刻の直後に検波を行うように、検波手段を制御する（ステップＳＴ４０−１、ＳＴ４０−２）。
【００６６】
以上のように、本実施の形態においては、トーン周波数が変更される時刻を予測して、検波タイミングを制御することによって、トーン周波数が変更していないのに、現在のトーン周波数を求めるような無駄な処理を減少できる。妨害を考えると、現在のトーン周波数を求めるための観測を行う際には、一般的に妨害を一時中止する必要があり、妨害効率が劣化するので、この処理の減少により、妨害効率を向上できる。
【００６７】
さらに、複数のＦＨ通信が存在する場合には、１つ１つのＦＨ通信がトーン周波数を変更する度に観測を行えば、各ＦＨ通信のトーン周波数の系列を求めることができる。しかし、複数のＦＨ通信がトーン周波数を変更してから観測を行っても、どのＦＨ通信がどのトーン周波数に変更したのかがわからなくなってしまう。トーン周波数が変更される時刻を予測して、検波タイミングを制御すれば、このような問題を防ぐことができる。
【００６８】
なお、本実施の形態においては、実施の形態１（図１）の検波タイミング発生手段１１の代わりに、検波タイミング制御手段４０を設けた例について説明したが、その場合に限らず、実施の形態２（図３）及び実施の形態３（図５）の検波タイミング発生手段１１の代わりに、検波タイミング制御手段４０を設けるようにしてもよく、その場合も同様の効果を得ることができる。
【００６９】
【発明の効果】
この発明は、ＦＨ通信の周波数ホッピングパターンを分析するためのＦＨ通信信号分析装置であって、予め設定された周波数帯域の信号のみを通過させるバンドパスフィルタと、バンドパスフィルタの出力信号の強度を計測する検波手段と、検波手段が計測を行うタイミングを出力して検波手段を制御する検波タイミング出力制御手段と、これまでのバンドパスフィルタの出力信号強度の系列と、これまでに推定したトーン周波数の系列とから、ＦＨ特徴を推定するＦＨ特徴推定手段と、ＦＨ特徴とバンドパスフィルタの出力信号強度とから、ＦＨ通信が現在用いているトーン周波数を推定するトーン推定手段と、を備え、上記ＦＨ特徴は、上記ＦＨ通信がトーン周波数を変更する周期の情報を少なくとも含むものであって、上記検波タイミング出力制御手段が、ＦＨ特徴を入力として、最も現在から近くで、ＦＨ通信がトーン周波数を変更する時刻を推定し、この時刻の直後に検波を行うように検波タイミングを制御する検波タイミング制御手段から構成されているＦＨ通信信号分析装置であるので、トーン周波数の変更時刻を考慮することによって、トーン周波数を変更する時刻前でトーン周波数が変更されていないにも関わらず、誤ったノイズをを検出してトーン周波数が変更されたと推定する危険性をなくすことができる。
【００７０】
また、この発明は、ＦＨ通信の周波数ホッピングパターンを分析するためのＦＨ通信信号分析装置であって、予め設定された周波数帯域の信号のみを通過させるバンドパスフィルタと、バンドパスフィルタの出力信号の強度を計測する検波手段と、上記検波手段が計測を行うタイミングを出力して上記検波手段を制御する検波タイミング出力制御手段と、ＦＨ通信が用いた周波数の系列に関して複数の候補を生成し、これらの候補を仮説として出力する仮説生成手段と、これまでのバンドパスフィルタの出力信号強度の系列と、上記仮説生成手段により生成された各仮説における周波数の系列の候補とから、各仮説においてＦＨ特徴を推定し、その仮説の評価値を求めるＦＨ特徴更新手段と、入力された複数の仮説の中から、それぞれの仮説の上記評価値を指標として、いくつかの仮説を選択し、選択されなかった他の仮説を除去する仮説除去手段と、入力された複数の仮説からＦＨ通信が現在用いている周波数を推定する仮説選択手段とを備え、上記ＦＨ特徴は、上記ＦＨ通信がトーン周波数を変更する周期の情報を少なくとも含むものであるＦＨ通信信号分析装置であるので、複数の仮説を生成し、かつ、保持しながら、トーン周波数を推定していくので、いったん、誤った仮説の評価値が良くなり、誤ったトーン周波数やＦＨ特徴が推定されても、後の観測結果から正しい仮説の評価値が良くなるため、その誤りを修正することができるので、より正しいトーン周波数の推定が可能となる。
【００７１】
また、この発明は、ＦＨ通信の周波数ホッピングパターンを分析するためのＦＨ通信信号分析装置であって、予め設定された周波数帯域の信号のみを通過させるバンドパスフィルタと、バンドパスフィルタの出力信号の強度を計測する検波手段と、上記検波手段が計測を行うタイミングを出力して上記検波手段を制御する検波タイミング出力制御手段と、複数のＦＨ通信が存在することを考慮し、ＦＨ通信の数及び各ＦＨ通信が用いた周波数の系列に関して複数の候補を生成し、これらの候補を仮説として出力する複数目標仮説生成手段と、これまでのバンドパスフィルタの出力信号強度の系列と、上記仮説生成手段により生成された各仮説における周波数の系列の候補とから、各仮説においてＦＨ特徴を推定し、その仮説の評価値を求める複数目標のＦＨ特徴更新手段と、入力された複数の仮説の中から、それぞれの仮説の上記評価値を指標として、いくつかの仮説を選択し、選択されなかった他の仮説を除去する仮説除去手段と、入力された複数の仮説からＦＨ通信が現在用いている周波数を推定する仮説選択手段とを備え、上記ＦＨ特徴は、上記ＦＨ通信がトーン周波数を変更する周期の情報を少なくとも含むものであるＦＨ通信信号分析装置であるので、複数のＦＨ通信が存在することを考慮して仮説を生成し、それぞれのＦＨ通信のトーン周波数を求めるので、各ＦＨ通信のトーン周波数の系列を正しく求めることができ、このため、特定のＦＨ通信だけ妨害を行うことができる。
【００７２】
また、検波タイミング出力制御手段が、検波手段の計測を行うタイミングを設定して、上記検波手段を制御する検波タイミング発生手段から構成されているので、同じ時刻にすべての検波手段が同時に検波を行うことができるので、トーン周波数を正しく分析することができる。
【００７３】
また、検波タイミング出力制御手段が、ＦＨ特徴を入力として、最も現在から近くで、ＦＨ通信が周波数を変更する時刻を推定し、この時刻の直後に検波を行うように検波タイミングを制御する検波タイミング制御手段から構成されているので、トーン周波数が変更される時刻を予測して、検波タイミングを制御することによって、トーン周波数が変更していないのに、現在のトーン周波数を求めるような無駄な処理を減少できる。
【００７４】
また、この発明は、ＦＨ通信の周波数ホッピングパターンを分析するためのＦＨ通信信号分析方法であって、予め設定された周波数帯域の信号のみを通過させるバンドパスフィルタリングステップと、バンドパスフィルタリングステップによる出力信号の強度を計測する検波ステップと、検波ステップにおいて計測を行うタイミングを出力して検波工程を制御する検波タイミング出力制御ステップと、これまでのバンドパスフィルタリングステップによる出力信号強度の系列と、これまでに推定したトーン周波数の系列とから、ＦＨ特徴を推定するＦＨ特徴推定ステップと、ＦＨ特徴とバンドパスフィルタの出力信号強度とから、ＦＨ通信が現在用いているトーン周波数を推定するトーン推定ステップとを備え、上記ＦＨ特徴は、上記ＦＨ通信がトーン周波数を変更する周期の情報を少なくとも含むものであって、上記検波タイミング出力制御手段が、ＦＨ特徴を入力として、最も現在から近くで、ＦＨ通信がトーン周波数を変更する時刻を推定し、この時刻の直後に検波を行うように検波タイミングを制御する検波タイミング制御ステップから構成されているＦＨ通信信号分析方法であるので、トーン周波数の変更時刻を考慮することによって、トーン周波数を変更する時刻前でトーン周波数が変更されていないにも関わらず、誤ったノイズを検出してトーン周波数が変更されたと推定する危険性をなくすことができる。
【００７５】
また、この発明は、ＦＨ通信の周波数ホッピングパターンを分析するためのＦＨ通信信号分析方法であって、予め設定された周波数帯域の信号のみを通過させるバンドパスフィルタリングステップと、バンドパスフィルタリングステップによる出力信号の強度を計測する検波ステップと、上記検波ステップにおいて計測を行うタイミングを出力して検波工程を制御する検波タイミング出力制御ステップと、ＦＨ通信が用いた周波数の系列に関して複数の候補を生成し、これらの候補を仮説として出力する仮説生成ステップと、これまでのバンドパスフィルタリングステップによる出力信号強度の系列と、各仮説においてＦＨ通信で用いたと推定される周波数の系列とから、各仮説においてＦＨ特徴を推定し、その仮説の評価値を求めるＦＨ特徴更新ステップと、入力された複数の仮説の中から、それぞれの仮説の評価値を指標としていくつかの仮説を選択し、選択されなかった他の仮説を除去する仮説除去ステップと、入力された複数の仮説からＦＨ通信が現在用いている周波数を推定する仮説選択ステップとを備え、上記ＦＨ特徴は、上記ＦＨ通信がトーン周波数を変更する周期の情報を少なくとも含むものであるＦＨ通信信号分析方法であるので、複数の仮説を生成し、かつ、保持しながら、トーン周波数を推定していくので、いったん、誤った仮説の評価値が良くなり、誤ったトーン周波数やＦＨ特徴が推定されても、後の観測結果から正しい仮説の評価値が良くなるため、その誤りを修正することができるので、より正しいトーン周波数の推定が可能となる。
【００７６】
また、この発明は、ＦＨ通信の周波数ホッピングパターンを分析するためのＦＨ通信信号分析方法であって、予め設定された周波数帯域の信号のみを通過させるバンドパスフィルタリングステップと、バンドパスフィルタリングステップにおける出力信号の強度を計測する検波ステップと、上記検波ステップにおける計測を行うタイミングを出力して検波工程を制御する検波タイミング出力制御ステップと、複数のＦＨ通信が存在することを考慮し、ＦＨ通信の数や、各ＦＨ通信が用いた周波数の系列に関して複数の候補を生成し、これらの候補を仮説として出力する複数目標仮説生成ステップと、これまでのバンドパスフィルタの出力信号強度の系列と、各仮説において各ＦＨ通信で用いたと考える周波数の系列とから、各仮説においてＦＨ特徴を推定し、その仮説の評価値を求める複数目標のＦＨ特徴更新ステップと、入力された複数の仮説の中から、それぞれの仮説の評価値を指標としていくつかの仮説を選択し、選択されなかった他の仮説を除去する仮説除去ステップと、入力された複数の仮説からＦＨ通信が現在用いている周波数を推定する仮説選択ステップとを備え、上記ＦＨ特徴は、上記ＦＨ通信がトーン周波数を変更する周期の情報を少なくとも含むものであるＦＨ通信信号分析方法であるので、複数のＦＨ通信が存在することを考慮して仮説を生成し、それぞれのＦＨ通信のトーン周波数を求めるので、各ＦＨ通信のトーン周波数の系列を正しく求めることができ、このため、特定のＦＨ通信だけ妨害を行うことができる。
【００７７】
また、検波タイミング出力制御ステップが、検波ステップの計測を行うタイミングを設定して、検波工程を制御する検波タイミング発生ステップから構成されているので、同じ時刻にすべての検波手段が同時に検波を行うことができるので、トーン周波数を正しく分析することができる。
【００７８】
また、検波タイミング出力制御手段が、ＦＨ特徴を入力として、最も現在から近くで、ＦＨ通信が周波数を変更する時刻を推定し、この時刻の直後に検波を行うように検波タイミングを制御する検波タイミング制御ステップから構成されているので、トーン周波数が変更される時刻を予測して、検波タイミングを制御することによって、トーン周波数が変更していないのに、現在のトーン周波数を求めるような無駄な処理を減少できる。
【図面の簡単な説明】
【図１】 本発明の実施の形態１におけるＦＨ通信信号分析装置の構成を示すブロック図である。
【図２】 本発明の実施の形態１におけるＦＨ通信信号分析方法の処理の流れを示す流れ図である。
【図３】 本発明の実施の形態２におけるＦＨ通信信号分析装置の構成を示すブロック図である。
【図４】 本発明の実施の形態２におけるＦＨ通信信号分析方法の処理の流れを示す流れ図である。
【図５】 本発明の実施の形態３におけるＦＨ通信信号分析装置の構成を示すブロック図である。
【図６】 本発明の実施の形態３におけるＦＨ通信信号分析方法の処理の流れを示す流れ図である。
【図７】 本発明の実施の形態４におけるＦＨ通信信号分析装置の構成を示すブロック図である。
【図８】 本発明の実施の形態４におけるＦＨ通信信号分析方法の処理の流れを示す流れ図である。
【図９】 従来のＦＨ通信信号分析装置の構成を示すブロック図である。
【図１０】 従来のＦＨ通信信号分析方法の処理の流れを示す流れ図である。
【符号の説明】
１０−１，１０−２，１０−Ｎ ＢＰＦ（バンドパスフィルタ）、１１ 検波タイミング発生手段、１２−１，１２−２，１２−Ｎ 検波手段、１３ 選択手段、２０ ＦＨ特徴推定手段、２１ トーン推定手段、３０ 仮説生成手段、３１ ＦＨ特徴更新手段、３２ 仮説除去手段、３３ 仮説選択手段、３５ 複数目標仮説生成手段、３６ 複数目標のＦＨ特徴更新手段、４０ 検波タイミング制御手段。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an FH communication signal analyzer for receiving a communication wave performed using a frequency hopping (hereinafter referred to as FH (Frequency Hopping)) communication method and analyzing a frequency hopping pattern of FH communication, and It relates to the analysis method.
[0002]
[Prior art]
FH communication is a communication method in which communication is performed using a certain frequency at a predetermined time, but the frequency is changed with the passage of time, and therefore communication using a wide frequency band in a long time. Is the method. Here, the frequency used by FH communication at a certain time is the tone frequency, and when the tone frequency is changed, the frequency that can be the next tone frequency is the tone frequency candidate, and a wide frequency band that is used for a long time Will be referred to as the FH band.
[0003]
When intercepting FH communications in real time without knowing the frequency hopping pattern in advance, such as when intercepting illegal and illegal FH communications and cracking down on them, analyze the tone frequency of FH communications in real time There is a need.
[0004]
Further, as one of the methods for disturbing the FH communication, there is a method of obtaining the tone frequency of the FH communication and performing the interference against this. Also in this case, it is necessary to analyze the tone frequency of FH communication in real time.
[0005]
In the conventional method for analyzing the tone frequency of FH communication in real time, first, a plurality of band pass filters (hereinafter referred to as BPF) having respective tone frequency candidates as pass frequencies are prepared, and FH communication signals are supplied to these. input. Then, the output of each BPF is compared to find the BPF having the largest output, and the passing frequency of this BPF is the tone frequency.
[0006]
FIG. 9 shows the configuration of an FH communication signal analyzer obtained by analogy with E.B. Felstead, “Follwer jammer considerations for frequency hopped spread spectrum”, MILCOM'98, pp.474-478, 1998. Here, N is the number of tone frequency candidates.
[0007]
In FIG. 9, 10-1, 10-2,..., 10-N are BPFs each having one of N tone frequency candidates as a pass frequency, and 11 is output by BPFs 10-1 to 10-N. The detection timing generation means 12-1, 12-2,..., 12-N for controlling the detection means (to be described later) so as to set the time for obtaining the signal strength of the received signal and obtaining the signal strength at that time are: Based on the control of the detection timing generation means 11, the detection means 13 for obtaining the output signal intensity of each BPF is obtained from the output signal intensity of each BPF output by each detection means 12-1, 12-2,. This is a selection means for selecting the BPF having the highest output signal intensity and outputting the passing frequency of the BPF as the tone frequency.
[0008]
Hereinafter, the operation of the FH communication signal analyzing apparatus shown in FIG. 9 will be described together with the flowchart of the FH communication signal analyzing method shown in FIG.
[0009]
First, as shown in FIG. 10, the BPFs 10-1 to 10-N receive FH communication signals as inputs, and output only signals included in the pass frequency range of the BPFs 10-1 to 10-N (step ST10). .
[0010]
Next, the detection timing generation means 11 sets a time for obtaining the output signal intensity such as the amplitude or power of the signal output from the BPF 10-1 to 10-N, and at this time, all the detection means 12-1 to 12-1-1. Control is performed so that 12-N obtains the signal strength (step ST11).
[0011]
As shown in FIG. 9, the detection means 12-1 to 12 -N are present corresponding to 1: 1 with respect to the BPFs 10-1 to 10 -N, and are based on the control of the detection timing generation means 11. The output signal strengths of the BPFs 10-1 to 10-N to be obtained are obtained and output to the selection means 13 (step ST12).
[0012]
The selection unit 13 selects a BPF having the highest output signal strength from the output signal strengths of the BPFs 10-1 to 10-N output from the detection units 12-1 to 12-N, and the passing frequency of the BPF is the tone frequency. As a result, the frequency is output (step ST13).
[0013]
[Problems to be solved by the invention]
However, in the above-described conventional FH communication signal analysis method or FH communication signal analysis apparatus, if there is a large noise in the output signal of a certain BPF, the frequency of this BPF is assumed to be the tone frequency. There was a problem of performing an incorrect analysis. Also, since it is assumed that there is one FH communication, when a plurality of FH communications use the same frequency band, the frequency hopping pattern of each FH communication or a specific FH communication is analyzed. There was a problem that it was not possible.
[0014]
The present invention has been made to solve such a problem, and avoids the risk of erroneously estimating the tone frequency even when a large noise (noise) is present in the output signal of the BPF. An object of the present invention is to obtain an FH communication signal analyzer and analysis method that can perform estimation, have high estimation accuracy, and can estimate the frequency hopping pattern of each FH communication even when there are a plurality of FH communications.
[0015]
[Means for Solving the Problems]
  The present invention is an FH communication signal analyzing apparatus for analyzing a frequency hopping pattern of FH communication, wherein a bandpass filter that passes only a signal in a preset frequency band and an intensity of an output signal of the bandpass filter are determined. Detection means for measuring, detection timing output control means for controlling the detection means by outputting the timing at which the detection means performs measurement, a sequence of output signal strengths of the bandpass filter so far, and the tone frequency estimated so far FH communication is currently used from FH feature estimation means for estimating FH features from a sequence of FH features, and output signal strengths of FH features and bandpass filters.toneTone estimation means for estimating frequencyThe FH feature includes at least information on the period at which the FH communication changes the tone frequency, and the detection timing output control means receives the FH feature as an input and is closest to the present time. It is composed of detection timing control means for estimating the time to change the tone frequency and controlling the detection timing so that detection is performed immediately after this time.This is an FH communication signal analyzer.
[0016]
  The present invention is also an FH communication signal analyzer for analyzing a frequency hopping pattern of FH communication, wherein a bandpass filter that passes only a signal in a preset frequency band, and an output signal of the bandpass filter A detection means for measuring intensity, a detection timing output control means for controlling the detection means by outputting timing at which the detection means performs measurement, and generating a plurality of candidates for the frequency series used by the FH communication, FH features in each hypothesis from a hypothesis generation means for outputting a candidate for a hypothesis, a series of bandpass filter output signal strengths so far, and a frequency series candidate in each hypothesis generated by the hypothesis generation means FH feature updating means for estimating the hypothesis and obtaining an evaluation value of the hypothesis, and each hypothesis from the plurality of input hypotheses Using the evaluation value as an index, hypothesis removal means for selecting several hypotheses and removing other hypotheses not selected, and hypothesis selection for estimating the frequency currently used by the FH communication from a plurality of input hypotheses With meansThe FH feature includes at least information on a period in which the FH communication changes the tone frequency.This is an FH communication signal analyzer.
[0017]
  The present invention is also an FH communication signal analyzer for analyzing a frequency hopping pattern of FH communication, wherein a bandpass filter that passes only a signal in a preset frequency band, and an output signal of the bandpass filter In consideration of the presence of a plurality of FH communications, the detection means for measuring the intensity, the detection timing output control means for controlling the detection means by outputting the timing at which the detection means performs measurement, and the number of FH communications. A plurality of target hypothesis generating means for generating a plurality of candidates for the frequency series used by each FH communication, and outputting these candidates as hypotheses; a series of output signal strengths of the bandpass filter so far; and the hypothesis generating means The FH feature is estimated in each hypothesis from the frequency series candidates in each hypothesis generated by, and the evaluation value of the hypothesis is obtained. FH feature update means for several targets and hypothesis removal that selects several hypotheses from among the plurality of input hypotheses using the evaluation value of each hypothesis as an index and removes other hypotheses that have not been selected And hypothesis selection means for estimating a frequency currently used by FH communication from a plurality of input hypotheses.The FH feature includes at least information on a period in which the FH communication changes the tone frequency.This is an FH communication signal analyzer.
[0018]
The detection timing output control means includes detection timing generation means for setting the timing at which the detection means performs measurement and controlling the detection means.
[0019]
The detection timing output control means estimates the time at which the FH communication changes the frequency closest to the present time with the FH feature as an input, and controls the detection timing so that detection is performed immediately after this time. It consists of control means.
[0020]
  In addition, the present invention is an FH communication signal analysis method for analyzing a frequency hopping pattern of FH communication, and includes a bandpass filtering step for allowing only a signal in a preset frequency band to pass, and an output by the bandpass filtering step A detection step for measuring the signal strength, a detection timing output control step for controlling the detection process by outputting the timing at which measurement is performed in the detection step, a series of output signal strengths by the conventional bandpass filtering step, and so far FH communication is currently used based on the FH feature estimation step for estimating the FH feature from the tone frequency sequence estimated in the above, and the output signal strength of the FH feature and the bandpass filter.toneA tone estimation step for estimating the frequency.The FH feature includes at least information on a period in which the FH communication changes the tone frequency, and the detection timing output control means receives the FH feature as an input and is closest to the present time, and the FH communication is a tone. It consists of a detection timing control step that estimates the time to change the frequency and controls the detection timing to detect immediately after this time.It is a FH communication signal analysis method.
[0021]
  In addition, the present invention is an FH communication signal analysis method for analyzing a frequency hopping pattern of FH communication, and includes a bandpass filtering step for allowing only a signal in a preset frequency band to pass, and an output by the bandpass filtering step A detection step for measuring the intensity of the signal, a detection timing output control step for controlling the detection process by outputting timing for measurement in the detection step, and generating a plurality of candidates for the frequency series used by the FH communication, From the hypothesis generation step for outputting these candidates as hypotheses, the sequence of output signal strengths by the bandpass filtering step so far, and the frequency sequence estimated to be used in FH communication in each hypothesis, FH features in each hypothesis FH characteristics that estimate the hypothesis and obtain the evaluation value of the hypothesis An update step, a hypothesis removal step that selects several hypotheses from among the plurality of input hypotheses using the evaluation value of each hypothesis as an index, and removes other hypotheses that are not selected, and a plurality of input hypotheses A hypothesis selection step of estimating a frequency currently used by FH communication from the hypothesis ofThe FH feature includes at least information on a period in which the FH communication changes the tone frequency.It is a FH communication signal analysis method.
[0022]
  In addition, the present invention is an FH communication signal analysis method for analyzing a frequency hopping pattern of FH communication, and includes a bandpass filtering step that allows only a signal in a preset frequency band to pass, and an output in the bandpass filtering step In consideration of the presence of a plurality of FH communications, a detection step for measuring the intensity of the signal, a detection timing output control step for controlling the detection process by outputting timing at which measurement is performed in the detection step, and the number of FH communications Or a plurality of target hypothesis generation steps for generating a plurality of candidates for a frequency sequence used by each FH communication, and outputting these candidates as hypotheses, a sequence of output signal strengths of the bandpass filter so far, and each hypothesis From the series of frequencies considered to be used in each FH communication, the F in each hypothesis A multi-target FH feature update step for estimating a feature and obtaining an evaluation value of the hypothesis, and selecting a plurality of hypotheses from a plurality of input hypotheses using each hypothesis evaluation value as an index A hypothesis removal step of removing other hypotheses that did not exist, and a hypothesis selection step of estimating a frequency currently used by the FH communication from a plurality of input hypothesesThe FH feature includes at least information on a period in which the FH communication changes the tone frequency.It is a FH communication signal analysis method.
[0023]
In addition, the detection timing output control step includes a detection timing generation step for controlling the detection process by setting the timing for measuring the detection step.
[0024]
The detection timing output control means estimates the time at which the FH communication changes the frequency closest to the present time with the FH feature as an input, and controls the detection timing so that detection is performed immediately after this time. It consists of control steps.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
  Embodiments 1 to 4 of the present invention will be described below with reference to the drawings. In each drawing, common elements are denoted by the same reference numerals, and redundant description is omitted. Here, in FH communication, it is assumed that the tone frequency is changed at a constant cycle.Hopping speed (orHopping cycle)It will be called Th. In this case, the time T ↓ i at which the tone frequency is changed i-th is obtained by the following equation.
[0026]
[Expression 1]

[0027]
Ts indicates the start time of FH communication. In addition, since it is not always possible to observe each FH communication from the beginning, it may be difficult to know the start time. In this case, with a certain time Ts ′ as a reference, the time when the tone frequency is changed to the i′th time is expressed by the following equation.
[0028]
[Expression 2]

[0029]
However, the integer N is the maximum integer in which the right side of the above expression is past the time Ts ′ when i ′ = 0. Φ can be obtained as φ = mod (Tc, Th), where Tc is one of the times when the tone frequency is changed. Here, φ is called a phase.
[0030]
Embodiment 1 FIG.
First, Embodiment 1 of the present invention will be described. FIG. 1 shows a block diagram of the FH communication signal analyzer in the first embodiment. In the figure, 10-1, 10-2,..., 10-N are BPFs that pass only signals of a preset frequency, and 11 is a detection unit that sets detection timings and controls detection means to be described later. The timing generators 12-1, 12-2,..., 12-N set the output signal strengths of the BPFs 10-1, 10-2,..., 10-N at the time controlled by the detection timing generator 11. A detecting means 20 for measuring, an FH feature estimating means 21 for estimating features of FH communication such as a hopping speed from a sequence of output signal strengths of each BPF so far and a sequence of tone frequencies estimated so far, 21 , Tone estimation means for estimating the frequency currently used by the FH communication from the FH feature and the output signal strength of each BPF.
[0031]
Hereinafter, the operation of the FH communication signal analyzer shown in FIG. 1 will be described with reference to the flowchart shown in FIG.
[0032]
The BPFs 10-1 to 10-N, the detection timing generation unit 11, and the detection units 12-1 to 12-N function in the same manner as in the past. (Steps ST10, ST11, ST12).
[0033]
Next, the FH feature estimation means 20 receives the output signal strength of each BPF output from each of the detection means 12-1 to 12-N and the tone frequency output from the tone estimation means 21, and first accumulates them. Then, the FH communication hopping speed Th or the hopping speed Th and the phase φ are estimated as the FH feature from the accumulated output signal intensity series of each BPF and the accumulated tone frequency series, and this is used as the tone estimation. It outputs to the means 21 (step ST20).
[0034]
For example, the number of times the tone frequency is changed can be obtained from the tone frequency series. Then, the hopping speed Th can be estimated by dividing the time during which the FH communication is observed by the number of times.
If the tone frequency estimated at a certain time is different from the tone frequency estimated at the next time, it is considered that the tone frequency has been changed within this time. Therefore, a time range series in which the tone frequency is changed can be obtained.
When the estimated hopping speed Th is given in the above equation (1) or (2), and an arbitrary value between 0 and Th is substituted for φ, and the phase φ is that value, the tone frequency A sequence of times Ti (or Ti ′) for changing the values is obtained. It is determined whether or not these times are included in the sequence of the time range in which the previously determined tone frequency is changed, and the included number Nt is determined. Then, by changing φ, φ that maximizes Nt is obtained. However, since it is considered that there are a plurality of φ having the same number Nt included, in this case, the range is obtained, for example, the central value is φ.
[0035]
The tone estimation means 21 first obtains a time series for changing the tone frequency from the FH features input from the FH feature estimation means 20. Next, it is determined whether or not the time for changing the tone frequency has passed since the time when the tone frequency was estimated previously. Finally, if it does not pass, the same tone frequency is output, and if it passes, the output signal strength of each BPF is compared, and the frequency of the BPF having the highest strength is output as the tone frequency (step ST21). .
[0036]
As described above, in the present embodiment, by considering the change time of the tone frequency, noise is erroneously detected even though the tone frequency is not changed before the time of changing the tone frequency. The risk of estimating that the tone frequency has been changed can be eliminated, and high estimation accuracy can be obtained.
[0037]
Embodiment 2. FIG.
Next, a second embodiment of the present invention will be described. FIG. 3 shows a block diagram of the FH communication signal analyzer in the second embodiment. In the figure, 30 is a hypothesis generation means that considers a plurality of candidates for the frequency sequence used by the FH communication and generates these candidates as hypotheses, 31 is a sequence of output signal strengths of each BPF so far, and hypotheses FH feature update means 32 for estimating FH communication characteristics such as hopping speed in each hypothesis from the frequency series candidates in each hypothesis generated by the generation means 30 and obtaining an evaluation value of the hypothesis is input. The hypothesis removing means 33 for selecting several hypotheses from the plurality of hypotheses using the evaluation value of each hypothesis as an index and removing the other hypotheses, is currently used by the FH communication from the plurality of inputted hypotheses. This is a hypothesis selection means for estimating the frequency that is present. Other configurations are the same as those shown in the first embodiment, and thus the same reference numerals are given and description thereof is omitted.
[0038]
The operation of the FH communication signal analyzer shown in FIG. 3 will be described below along the flowchart shown in FIG. The time at which detection was performed is assumed to be t ↓ i (1 ≦ i ≦ Nm). In this apparatus, with respect to FH communication, a sequence {f} = {f (t ↓ 1), f (t ↓ 2),..., F (t ↓ Nm) of tone frequency f (t ↓ i) of FH communication at each time. )} And a sequence {p} = {p (t ↓ 1), p (t ↓ 2),..., P (t ↓ Nm)} of the signal strength p (t ↓ i) and the FH feature Th , Φ is obtained. Therefore, if any value is assumed for these, it becomes a candidate for a solution. This solution candidate is called a hypothesis.
[0039]
The BPFs 10-1 to 10-N, the detection timing generation unit 11, and the detection units 12-1 to 12-N function in the same manner as in the first embodiment. (Steps ST10, ST11, ST12).
[0040]
The hypothesis generation means 30 receives the hypothesis fed back from the hypothesis removal means 32 and the output signal strength of the BPF output by each detection means. First, a BPF that is considered to contain an FH communication signal is selected from the output signal strength of the BPF output by each detection means, using a target detection method in a radar or the like. When such a detection method is used, a plurality of BPFs may be selected, or none of the BPFs may be selected. If none is selected, the output signal strength of each BPF is searched for the strongest, and the BPF outputting the signal is selected.
[0041]
Next, when no hypothesis is input from the hypothesis removing unit 32, the frequency of the BPF is the current tone frequency in each of the selected BPFs, and the signal strength of the selected BPF is the signal of the tone frequency. Generate a hypothesis of strength. Therefore, as many hypotheses as the number of selected BPFs are generated.
For example, when two BPFs are selected, their frequencies are f1 and f2, and the signal strengths are p1 and p2, the tone frequency sequence is {f} = {f1} and the reception strength sequence is {p}. = {P1}, the hypothesis where the FH feature is unknown, and the hypothesis where the tone frequency sequence is {f} = {f2}, the received intensity sequence is {p} = {p2}, and the FH feature is unknown 2 Two hypotheses are generated.
[0042]
  When a hypothesis is input from the hypothesis removing unit 32, for each hypothesis, any frequency of the selected BPF is the current tone frequency, and the signal strength of the BPF is a signal of the tone frequency. We add that they are strengths, and let each be a hypothesis. Therefore, there are Ni hypotheses input and the selected BPFN fIf there are, a new hypothesis is generated that describes Ni × Nf total up to the current tone frequency.
  For example, when two BPFs are selected, their frequencies are f1 and f2, and the signal strengths are p1 and p2, the tone frequency sequence is {f} ↓ 1, and the signal strength sequence is {p} ↓. 1. When the above processing is performed on the hypothesis of FH features Th ↓ 1, φ ↓ 1, the tone frequency sequence is {{f} ↓ 1, f1}, and the signal strength sequence is {{p} ↓ 1, p1}, FH features Th ↓ 1, φ ↓ 1, the tone frequency sequence is {{f} ↓ 1, f2}, and the signal strength sequence is {{p} ↓ 1, p2} , FH features Th ↓ 1, φ ↓ 1, a total of two hypotheses are generated.
[0043]
After generating the hypotheses in this way, finally, these hypotheses are output to the FH feature update means 31 (step ST30).
[0044]
The FH feature update unit 31 receives one or more hypotheses from the hypothesis generation unit. First, in each hypothesis inputted, the FH feature is obtained in the same manner as the feature estimation means in the first embodiment.
Next, for each hypothesis, an evaluation value is obtained and added to each hypothesis. For example, Nt obtained when obtaining the phase φ, or the sum Σ of the signal intensity p (t ↓ i) included in the signal intensity series {p} described in the hypothesis is used as an evaluation value, or Nt × Σ is evaluated. It can be considered as a value.
Finally, an FH feature is obtained, and a hypothesis added with an evaluation value is output (step ST31).
[0045]
The hypothesis removal means 32 receives one or more hypotheses output from the FH feature estimation means 31 as input, compares evaluation values added to these hypotheses, selects some hypotheses with good evaluation values, and selects these hypotheses. And other hypotheses are removed (step ST32).
For this selection, select a number of hypotheses that have been determined in advance and select only those hypotheses that have an evaluation value better than a predetermined evaluation value. Possible ways to do this.
[0046]
In the hypothesis selection means 33, the hypothesis output from the hypothesis removal means 32 is input, and tone frequencies are estimated from these hypotheses and output (step ST33).
As a method for estimating the tone frequency, a hypothesis with the best evaluation value is selected, and the current tone frequency in this hypothesis is set as the current tone frequency estimated by the present apparatus. A method may be considered in which the tone frequency is examined, and the frequency assumed to be the tone frequency according to the most hypotheses is used as the current tone frequency estimated by the present apparatus.
[0047]
As described above, in the present embodiment, the tone frequency is estimated while generating and holding a plurality of hypotheses, so that the evaluation value of the wrong hypothesis is improved once and the erroneous tone frequency is improved. Even if the FH feature is estimated, the evaluation value of the correct hypothesis is improved from the subsequent observation result, so that the error can be corrected. Therefore, a more accurate tone frequency can be estimated.
[0048]
Embodiment 3 FIG.
Next, a third embodiment of the present invention will be described. FIG. 5 shows a block diagram of the FH communication signal analyzing apparatus according to the third embodiment. In the figure, in consideration of the existence of a plurality of FH communications, 35 designates a plurality of targets regarding the number of FH communications and a sequence of frequencies used by each FH communications, and generating these candidates as hypotheses. The hypothesis generation means 36, based on the output signal strength series of each BPF so far and the frequency series candidates in each hypothesis generated by the multiple target hypothesis generation means 35, the hopping speed of each FH communication in each hypothesis This is a multi-target FH feature update means for estimating the features of FH communication, etc. and obtaining the evaluation value of the hypothesis. Since other configurations are the same as those shown in the first and second embodiments, the same reference numerals are given and description thereof is omitted.
[0049]
Here, assuming that there is a possibility that a plurality of FH communications may be performed simultaneously, the number of FH communications Nc and the respective FH communications j (( 1 ≦ j ≦ Nc) tone frequency f ↓ j (t ↓ i) sequence {f ↓ j} and its signal strength p ↓ j (t ↓ i) sequence {p ↓ j} A candidate solution that assumes a certain value for the FH features Th ↓ j and φ ↓ j of the FH communication is called a hypothesis.
[0050]
The operation of the FH communication signal analyzer shown in FIG. 5 will be described below along the flowchart shown in FIG.
[0051]
The BPFs 10-1 to 10-N, the detection timing generation unit 11, the detection units 12-1 to 12-N, the hypothesis removal unit 32, and the hypothesis selection unit 33 function in the same manner as in the second embodiment. (Steps ST10, ST11, ST12, ST32, ST33).
[0052]
The multi-target hypothesis generation means 35 receives the hypothesis fed back from the hypothesis removal means 32 and the output signal strength of each BPF output from each detection means. First, in the same manner as the hypothesis generation means in the second embodiment, one or more BPFs that are considered to output a signal including a communication signal are selected.
[0053]
Next, when no hypothesis is input from the hypothesis removing means 32, if the number of selected BPF frequencies is Nf, the output signal of each BPF is a signal of a tone frequency of a certain FH communication. All combinations are considered as whether noise is detected erroneously, and 2 Nf raised hypotheses are generated.
[0054]
For example, if two BPFs are selected, their frequencies are f1 and f2, and their signal strengths are p1 and p2, the number of FH communications Nc is 2, and the sequence of tone frequencies of the first FH communications is {f } = {F1}, the received intensity sequence is {p} = {p1}, the tone frequency sequence of the second FH communication is {f} = {f2}, and the received intensity sequence is {p} = { p2}, the assumption that each FH feature is unknown, the number of FH communications Nc is 1, the tone frequency sequence is {f} = {f1}, and the received intensity sequence is {p} = {p1} , FH feature unknown hypothesis, FH communication number Nc is 1, tone frequency sequence is {f} = {f2}, received intensity sequence is {p} = {p2}, and FH feature is unknown The combination of the hypothesis and the hypothesis in which the number of FH communications Nc is 0 generates 4 (= 2 squared) hypotheses.
[0055]
Further, when Ni hypotheses are input from the hypothesis removing means 32, the following processing is performed on each hypothesis to generate a plurality of hypotheses. Assuming that the tone frequency of the FH communication assumed in each hypothesis is one of the frequencies of the selected BPF, or that this FH communication has already ended, all cases are considered. In some cases, it is assumed that the frequency of the BPF, which has not been the tone frequency of any FH communication so far, is a noise frequency detected erroneously or the tone frequency of a new FH communication. Think of a combination. Then, the tone frequency and signal strength of each FH communication assumed in each combination are added to the original hypothesis, and each is generated as a hypothesis.
[0056]
When two BPFs are selected, their frequencies are f1 and f2, and their signal strengths are p1 and p2, the number of FH communications Nc is 1, and the tone frequency sequence is {f} ↓ 1 An example in which the above processing is performed on a hypothesis whose signal intensity series is {p} ↓ 1, FH feature Th ↓ 1, and φ ↓ 1 will be described.
[0057]
First, there are three possible cases where the current tone frequency of the FH communication C assumed in this hypothesis is f1, f2 and FH communication C has already ended.
Next, when the tone frequency of the FH communication C is f1, the f2 that is not the tone frequency of the FH communication C is the tone frequency of the new FH communication or the noise is erroneously detected. The number of FH communication Nc is 2, the tone frequency sequence of the first FH communication is {{f} ↓ 1, f1}, the signal strength sequence is {{p} ↓ 1, p1}, and the FH feature Th ↓ 1, φ ↓ 1, the tone frequency sequence of the second FH communication is {f2}, the signal strength sequence is {p2}, the FH feature is unknown, and the number of FH communications Nc is 1. , FH communication tone frequency series is {{f} ↓ 1, f1}, signal strength series is {{p} ↓ 1, p1}, FH features Th ↓ 1, φ ↓ 1 A hypothesis is generated.
When the tone frequency of the FH communication C is f2, since f1 is the tone frequency of the new FH communication or noise is detected by mistake, two hypotheses are generated in the same manner. Furthermore, when this FH communication C is completed, f1 and f2 are the detected tone frequencies or noises of the new FH communication, respectively, so 2 × 2 combinations are possible and four hypotheses are possible. Is generated. Thus, a total of 8 hypotheses are generated.
[0058]
After the hypotheses are generated in this way, finally, these hypotheses are output to the multi-target FH feature update means 36 (step ST35).
[0059]
The multi-target FH feature update unit 36 obtains FH features in the same manner as the FH feature update unit in the second embodiment. However, in these hypotheses, there may be a plurality of FH communications, and in this case, FH characteristics are obtained for each FH communications.
Next, the evaluation value is obtained for each hypothesis. At this time, there may be a case where a plurality of FH communications are assumed. In this case, for each FH communication, an evaluation value is calculated in the same manner as in the second embodiment, and the sum or average value is calculated as a hypothesis evaluation value. And
Finally, an FH feature is obtained, and a hypothesis added with an evaluation value is output (step ST36).
[0060]
As described above, in the present embodiment, a hypothesis is generated in consideration of the existence of a plurality of FH communications, and the tone frequency of each FH communication is obtained. Can be sought. For this reason, only specific FH communication can be disturbed.
[0061]
Embodiment 4 FIG.
Next, a fourth embodiment of the present invention will be described. FIG. 7 shows a block diagram of the FH communication signal analyzing apparatus according to the fourth embodiment. In the figure, reference numeral 40 denotes detection timing control means for estimating the detection timing so that FH communication is used to estimate the time at which the FH communication changes the frequency, and the detection is performed immediately after this time, using the FH feature as an input. It is. Since other configurations are the same as those shown in the first embodiment, the same reference numerals are given and description thereof is omitted.
[0062]
The operation of the FH communication signal analyzer shown in FIG. 7 will be described below with reference to the flowchart shown in FIG.
[0063]
The BPFs 10-1 to 10-N, the detection units 12-1 to 12-N, and the tone estimation unit 21 function in the same manner as in the first embodiment (steps ST10, ST12, and ST21).
[0064]
The FH feature estimation means 20 functions in the same manner as in the first embodiment. However, the FH feature is also output to the detection timing control means (step ST20). Further, the FH feature may be estimated by the detection timing control means by the FH feature update means 31 shown in the second embodiment or the multi-target FH feature update means 36 shown in the third embodiment. However, in the case of the FH feature update unit 31 and the multi-target FH feature update unit 36, different FH features are described in a plurality of hypotheses, or a plurality of FH communication is assumed in each hypothesis. Therefore, all these FH features are output.
[0065]
The detection timing control means 40 receives the FH feature as an input, and predicts the time when the tone frequency is changed at the nearest time from the present time using the above-described equations (1) and (2). However, when a plurality of FH features are input, the time at which the tone frequency is changed at the nearest time is predicted using Equation (1) or Equation (2), respectively, and further, Find the nearest time. And a detection means is controlled so that it may detect immediately after the calculated | required time (step ST40-1, ST40-2).
[0066]
As described above, in the present embodiment, by predicting the time at which the tone frequency is changed and controlling the detection timing, the tone frequency is not changed but the current tone frequency is obtained. Wasteful processing can be reduced. Considering interference, when performing observations to determine the current tone frequency, it is generally necessary to temporarily stop the interference, and the interference efficiency deteriorates, so this processing reduction can improve the interference efficiency. .
[0067]
Further, in the case where there are a plurality of FH communications, if each FH communication is observed every time the tone frequency is changed, a sequence of tone frequencies of each FH communication can be obtained. However, even if observation is performed after a plurality of FH communications change tone frequencies, it becomes impossible to know which FH communications have changed to which tone frequency. Such a problem can be prevented by predicting the time at which the tone frequency is changed and controlling the detection timing.
[0068]
In the present embodiment, the example in which the detection timing control means 40 is provided in place of the detection timing generation means 11 of the first embodiment (FIG. 1) has been described. Detection timing control means 40 may be provided instead of the detection timing generation means 11 of FIG. 2 (FIG. 3) and Embodiment 3 (FIG. 5), and in this case, the same effect can be obtained.
[0069]
【The invention's effect】
  The present invention is an FH communication signal analyzing apparatus for analyzing a frequency hopping pattern of FH communication, wherein a bandpass filter that passes only a signal in a preset frequency band and an intensity of an output signal of the bandpass filter are determined. Detection means for measuring, detection timing output control means for controlling the detection means by outputting the timing at which the detection means performs measurement, a sequence of output signal strengths of the bandpass filter so far, and the tone frequency estimated so far FH communication is currently used from FH feature estimation means for estimating FH features from a sequence of FH features, and output signal strengths of FH features and bandpass filters.toneTone estimation means for estimating frequencyThe FH feature includes at least information on the period at which the FH communication changes the tone frequency, and the detection timing output control means receives the FH feature as an input and is closest to the present time. It is composed of detection timing control means for estimating the time to change the tone frequency and controlling the detection timing so that detection is performed immediately after this time.Since this is an FH communication signal analyzer, the tone frequency is detected by detecting the erroneous noise even though the tone frequency is not changed before the time when the tone frequency is changed by considering the change time of the tone frequency. It is possible to eliminate the risk of estimating that has been changed.
[0070]
  The present invention is also an FH communication signal analyzer for analyzing a frequency hopping pattern of FH communication, wherein a bandpass filter that passes only a signal in a preset frequency band, and an output signal of the bandpass filter A detection means for measuring intensity, a detection timing output control means for controlling the detection means by outputting timing at which the detection means performs measurement, and generating a plurality of candidates for the frequency series used by the FH communication, FH features in each hypothesis from a hypothesis generation means for outputting a candidate for a hypothesis, a series of bandpass filter output signal strengths so far, and a frequency series candidate in each hypothesis generated by the hypothesis generation means FH feature updating means for estimating the hypothesis and obtaining an evaluation value of the hypothesis, and each hypothesis from the plurality of input hypotheses Using the evaluation value as an index, hypothesis removal means for selecting several hypotheses and removing other hypotheses not selected, and hypothesis selection for estimating the frequency currently used by the FH communication from a plurality of input hypotheses With meansThe FH feature includes at least information on a period in which the FH communication changes the tone frequency.Since it is an FH communication signal analyzer, the tone frequency is estimated while generating and holding a plurality of hypotheses, so that the evaluation value of the wrong hypothesis is improved once, and the wrong tone frequency and FH feature Even if is estimated, since the evaluation value of the correct hypothesis is improved from the subsequent observation result, the error can be corrected, so that it is possible to estimate the tone frequency more correctly.
[0071]
  The present invention is also an FH communication signal analyzer for analyzing a frequency hopping pattern of FH communication, wherein a bandpass filter that passes only a signal in a preset frequency band, and an output signal of the bandpass filter In consideration of the presence of a plurality of FH communications, the detection means for measuring the intensity, the detection timing output control means for controlling the detection means by outputting the timing at which the detection means performs measurement, and the number of FH communications. A plurality of target hypothesis generating means for generating a plurality of candidates for the frequency series used by each FH communication, and outputting these candidates as hypotheses; a series of output signal strengths of the bandpass filter so far; and the hypothesis generating means The FH feature is estimated in each hypothesis from the frequency series candidates in each hypothesis generated by, and the evaluation value of the hypothesis is obtained. FH feature update means for several targets and hypothesis removal that selects several hypotheses from among the plurality of input hypotheses using the evaluation value of each hypothesis as an index and removes other hypotheses that have not been selected And hypothesis selection means for estimating a frequency currently used by FH communication from a plurality of input hypotheses.The FH feature includes at least information on a period in which the FH communication changes the tone frequency.Since it is an FH communication signal analyzer, a hypothesis is generated in consideration of the existence of a plurality of FH communications, and the tone frequency of each FH communication is obtained. Therefore, only specific FH communication can be disturbed.
[0072]
Further, since the detection timing output control means is configured from detection timing generation means for setting the timing for measuring the detection means and controlling the detection means, all the detection means simultaneously detect at the same time. The tone frequency can be analyzed correctly.
[0073]
The detection timing output control means estimates the time at which the FH communication changes the frequency closest to the present time with the FH feature as an input, and controls the detection timing so that detection is performed immediately after this time. Since it is composed of the control means, by predicting the time when the tone frequency is changed and controlling the detection timing, wasteful processing such as obtaining the current tone frequency even though the tone frequency has not changed Can be reduced.
[0074]
  In addition, the present invention is an FH communication signal analysis method for analyzing a frequency hopping pattern of FH communication, and includes a bandpass filtering step for allowing only a signal in a preset frequency band to pass, and an output by the bandpass filtering step A detection step for measuring the signal strength, a detection timing output control step for controlling the detection process by outputting the timing at which measurement is performed in the detection step, a series of output signal strengths by the conventional bandpass filtering step, and so far FH communication is currently used based on the FH feature estimation step for estimating the FH feature from the tone frequency sequence estimated in the above, and the output signal strength of the FH feature and the bandpass filter.toneA tone estimation step for estimating the frequency.The FH feature includes at least information on a period in which the FH communication changes the tone frequency, and the detection timing output control means receives the FH feature as an input and is closest to the present time, and the FH communication is a tone. It consists of a detection timing control step that estimates the time to change the frequency and controls the detection timing to detect immediately after this time.Since this is an FH communication signal analysis method, by taking into account the change time of the tone frequency, erroneous noise is detected even though the tone frequency is not changed before the time of changing the tone frequency.InspectThe risk of estimating that the tone frequency has been changed can be eliminated.
[0075]
  In addition, the present invention is an FH communication signal analysis method for analyzing a frequency hopping pattern of FH communication, and includes a bandpass filtering step for allowing only a signal in a preset frequency band to pass, and an output by the bandpass filtering step A detection step for measuring the intensity of the signal, a detection timing output control step for controlling the detection process by outputting timing for measurement in the detection step, and generating a plurality of candidates for the frequency series used by the FH communication, From the hypothesis generation step for outputting these candidates as hypotheses, the sequence of output signal strengths by the bandpass filtering step so far, and the frequency sequence estimated to be used in FH communication in each hypothesis, FH features in each hypothesis FH characteristics that estimate the hypothesis and obtain the evaluation value of the hypothesis An update step, a hypothesis removal step that selects several hypotheses from among the plurality of input hypotheses using the evaluation value of each hypothesis as an index, and removes other hypotheses that are not selected, and a plurality of input hypotheses A hypothesis selection step of estimating a frequency currently used by FH communication from the hypothesis ofThe FH feature includes at least information on a period in which the FH communication changes the tone frequency.Since the FH communication signal analysis method is used, the tone frequency is estimated while generating and holding a plurality of hypotheses, so that the evaluation value of the wrong hypothesis is improved once, and the wrong tone frequency and FH characteristics are improved. Even if is estimated, since the evaluation value of the correct hypothesis is improved from the subsequent observation result, the error can be corrected, so that it is possible to estimate the tone frequency more correctly.
[0076]
  In addition, the present invention is an FH communication signal analysis method for analyzing a frequency hopping pattern of FH communication, and includes a bandpass filtering step that allows only a signal in a preset frequency band to pass, and an output in the bandpass filtering step In consideration of the presence of a plurality of FH communications, a detection step for measuring the intensity of the signal, a detection timing output control step for controlling the detection process by outputting timing at which measurement is performed in the detection step, and the number of FH communications Or a plurality of target hypothesis generation steps for generating a plurality of candidates for a frequency sequence used by each FH communication, and outputting these candidates as hypotheses, a sequence of output signal strengths of the bandpass filter so far, and each hypothesis From the series of frequencies considered to be used in each FH communication, the F in each hypothesis A multi-target FH feature update step for estimating a feature and obtaining an evaluation value of the hypothesis, and selecting a plurality of hypotheses from a plurality of input hypotheses using each hypothesis evaluation value as an index A hypothesis removal step of removing other hypotheses that did not exist, and a hypothesis selection step of estimating a frequency currently used by the FH communication from a plurality of input hypothesesThe FH feature includes at least information on a period in which the FH communication changes the tone frequency.Since this is an FH communication signal analysis method, a hypothesis is generated in consideration of the existence of a plurality of FH communications, and the tone frequency of each FH communication is obtained. Therefore, only specific FH communication can be disturbed.
[0077]
Also, the detection timing output control step consists of a detection timing generation step that controls the detection process by setting the timing for measuring the detection step, so that all detection means simultaneously detect at the same time Therefore, the tone frequency can be analyzed correctly.
[0078]
The detection timing output control means estimates the time at which the FH communication changes the frequency closest to the present time with the FH feature as an input, and controls the detection timing so that detection is performed immediately after this time. Because it is composed of control steps, it is a wasteful process to calculate the current tone frequency even though the tone frequency has not changed by predicting the time when the tone frequency is changed and controlling the detection timing. Can be reduced.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of an FH communication signal analyzer according to Embodiment 1 of the present invention.
FIG. 2 is a flowchart showing a process flow of the FH communication signal analysis method according to the first embodiment of the present invention.
FIG. 3 is a block diagram showing a configuration of an FH communication signal analyzer according to Embodiment 2 of the present invention.
FIG. 4 is a flowchart showing a process flow of an FH communication signal analysis method according to Embodiment 2 of the present invention.
FIG. 5 is a block diagram showing a configuration of an FH communication signal analyzer according to Embodiment 3 of the present invention.
FIG. 6 is a flowchart showing a process flow of an FH communication signal analysis method according to Embodiment 3 of the present invention.
FIG. 7 is a block diagram showing a configuration of an FH communication signal analysis apparatus according to Embodiment 4 of the present invention.
FIG. 8 is a flowchart showing a process flow of an FH communication signal analysis method according to Embodiment 4 of the present invention.
FIG. 9 is a block diagram showing a configuration of a conventional FH communication signal analyzer.
FIG. 10 is a flowchart showing a process flow of a conventional FH communication signal analysis method.
[Explanation of symbols]
10-1, 10-2, 10-N BPF (band pass filter), 11 detection timing generation means, 12-1, 12-2, 12-N detection means, 13 selection means, 20 FH feature estimation means, 21 tones Estimation means, 30 hypothesis generation means, 31 FH feature update means, 32 hypothesis removal means, 33 hypothesis selection means, 35 multi-target hypothesis generation means, 36 multi-target FH feature update means, 40 detection timing control means.

Claims (10)

An FH communication signal analyzer for analyzing a frequency hopping pattern of FH communication,
A band-pass filter that passes only signals in a preset frequency band; and
Detection means for measuring the intensity of the output signal of the bandpass filter;
Detection timing output control means for outputting the timing at which the detection means performs measurement and controlling the detection means;
FH feature estimation means for estimating FH features from a sequence of output signal strengths of the bandpass filter so far and a sequence of tone frequencies estimated so far;
Tone estimation means for estimating the tone frequency currently used by the FH communication from the FH feature and the output signal strength of the bandpass filter;
With
The FH feature includes at least information of a period in which the FH communication changes a tone frequency,
The detection timing output control means is
It is composed of detection timing control means that estimates the time at which the FH communication changes the tone frequency using the FH feature as input, and controls the detection timing so that detection is performed immediately after this time. FH communication signal analyzer characterized by this. An FH communication signal analyzer for analyzing a frequency hopping pattern of FH communication,
A band-pass filter that passes only signals in a preset frequency band; and
Detection means for measuring the intensity of the output signal of the bandpass filter;
Detection timing output control means for outputting the timing at which the detection means performs measurement and controlling the detection means;
Hypothesis generation means for generating a plurality of candidates for a frequency sequence used by FH communication and outputting these candidates as hypotheses;
FH feature is estimated in each hypothesis from the conventional output signal intensity series of the bandpass filter and the frequency series candidates in each hypothesis generated by the hypothesis generation means, and the evaluation value of the hypothesis is obtained. Feature update means;
A hypothesis removing means for selecting several hypotheses from among the plurality of inputted hypotheses, using the evaluation value of each hypothesis as an index, and removing other hypotheses not selected;
A hypothesis selection means for estimating a frequency currently used by the FH communication from a plurality of hypotheses input ;
The FH communication signal analyzing apparatus, wherein the FH feature includes at least information on a period in which the FH communication changes a tone frequency . An FH communication signal analyzer for analyzing a frequency hopping pattern of FH communication,
A band-pass filter that passes only signals in a preset frequency band; and
Detection means for measuring the intensity of the output signal of the bandpass filter;
Detection timing output control means for outputting the timing at which the detection means performs measurement and controlling the detection means;
In consideration of the existence of a plurality of FH communications, a plurality of target hypothesis generating means for generating a plurality of candidates for the number of FH communications and the frequency series used by each FH communications, and outputting these candidates as hypotheses;
A plurality of FH features are estimated in each hypothesis from a sequence of output signal strengths of the bandpass filter so far and a frequency sequence candidate in each hypothesis generated by the hypothesis generation means, and an evaluation value of the hypothesis is obtained. A target FH feature update means;
A hypothesis removing means for selecting several hypotheses from among the plurality of inputted hypotheses, using the evaluation value of each hypothesis as an index, and removing other hypotheses not selected;
A hypothesis selection means for estimating a frequency currently used by the FH communication from a plurality of hypotheses input ;
The FH communication signal analyzing apparatus, wherein the FH feature includes at least information on a period in which the FH communication changes a tone frequency . The detection timing output control means is
4. The FH communication signal analyzing apparatus according to claim 1, further comprising: a detection timing generation unit configured to set a timing at which the detection unit performs measurement and to control the detection unit. The detection timing output control means is
It is composed of detection timing control means for estimating the time at which the FH communication changes the frequency by using the FH feature as input and controlling the detection timing so that detection is performed immediately after this time. The FH communication signal analyzer according to claim 2 or 3, characterized in that An FH communication signal analysis method for analyzing a frequency hopping pattern of FH communication,
A bandpass filtering step for passing only signals in a preset frequency band; and
A detection step for measuring the intensity of the output signal by the bandpass filtering step;
A detection timing output control step for controlling the detection process by outputting the timing for measurement in the detection step;
An FH feature estimation step for estimating an FH feature from a sequence of output signal strengths obtained by the above bandpass filtering step and a sequence of tone frequencies estimated so far;
A tone estimation step for estimating a tone frequency currently used by the FH communication from the FH feature and the output signal strength of the bandpass filter;
The FH feature includes at least information of a period in which the FH communication changes a tone frequency,
The detection timing output control means is
It consists of a detection timing control step that estimates the time when the FH communication changes the tone frequency, using the FH feature as input, and controls the detection timing so that detection is performed immediately after this time. FH communication signal analysis method characterized by the above. An FH communication signal analysis method for analyzing a frequency hopping pattern of FH communication,
A bandpass filtering step for passing only signals in a preset frequency band; and
A detection step for measuring the intensity of the output signal by the bandpass filtering step;
A detection timing output control step for controlling the detection process by outputting the timing for measurement in the detection step;
A hypothesis generation step of generating a plurality of candidates for the frequency sequence used by the FH communication and outputting these candidates as hypotheses;
An FH feature that estimates an FH feature in each hypothesis and obtains an evaluation value of the hypothesis from a sequence of output signal strengths obtained by the previous bandpass filtering step and a sequence of frequencies estimated to be used in FH communication in each hypothesis. An update step;
A hypothesis removal step of selecting several hypotheses from among the plurality of input hypotheses using the evaluation value of each hypothesis as an index, and removing other hypotheses not selected;
A hypothesis selection step of estimating a frequency currently used by the FH communication from a plurality of hypotheses input ,
The FH communication signal analysis method characterized in that the FH feature includes at least information on a period in which the FH communication changes a tone frequency . An FH communication signal analysis method for analyzing a frequency hopping pattern of FH communication,
A bandpass filtering step for passing only signals in a preset frequency band; and
A detection step for measuring the intensity of the output signal in the bandpass filtering step;
A detection timing output control step for controlling the detection process by outputting a timing for performing measurement in the detection step;
In consideration of the existence of a plurality of FH communications, a plurality of target hypothesis generation steps for generating a plurality of candidates for the number of FH communications and a sequence of frequencies used by each FH communications, and outputting these candidates as hypotheses;
A multi-target FH that estimates FH characteristics in each hypothesis and obtains an evaluation value of the hypothesis from a sequence of output signal strengths of the bandpass filter so far and a frequency sequence considered to be used in each FH communication in each hypothesis. A feature update step;
A hypothesis removal step of selecting several hypotheses from among the plurality of input hypotheses using the evaluation value of each hypothesis as an index, and removing other hypotheses not selected;
A hypothesis selection step of estimating a frequency currently used by the FH communication from a plurality of hypotheses input ,
The FH communication signal analysis method characterized in that the FH feature includes at least information on a period in which the FH communication changes a tone frequency . The detection timing output control step is
9. The FH communication signal analysis method according to claim 6, further comprising: a detection timing generation step for controlling the detection step by setting a timing at which the detection step is measured. The detection timing output control means is
It is composed of a detection timing control step that estimates the time at which the FH communication changes the frequency, using the FH feature as input, and controls the detection timing so that detection is performed immediately after this time. 9. The FH communication signal analysis method according to claim 7 or 8, wherein

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