JPH06105901B2 - Wireless communication system - Google Patents
Wireless communication systemInfo
- Publication number
- JPH06105901B2 JPH06105901B2 JP1111795A JP11179589A JPH06105901B2 JP H06105901 B2 JPH06105901 B2 JP H06105901B2 JP 1111795 A JP1111795 A JP 1111795A JP 11179589 A JP11179589 A JP 11179589A JP H06105901 B2 JPH06105901 B2 JP H06105901B2
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- transmission
- power
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Description
本発明は無線通信方式、特に短波を利用した無線通信で
第三者にその通信を傍受されることを極力避けるための
通信方式に関する。The present invention relates to a wireless communication system, and more particularly to a communication system for avoiding being intercepted by a third party in wireless communication using short waves.
【従来の技術】 短波を利用した通信では、その電波伝播の特性上、比較
的小さい電力で遠距離通信が可能であるという特徴をも
っている。 短波の電波伝播特性は、時刻、季節、太陽黒点数等、極
めて複雑なパラメータに支配される。そのため、長期的
にみて平均的な伝播特性の予測は可能であっても、実際
の通信の場で、最低何ワットの送信電力で通信が可能で
あるかは予測することが困難である。このために通常
は、許可された最大の送信電力で通信を行なっている。2. Description of the Related Art Communication utilizing short waves is characterized by the fact that it is possible to carry out long-distance communication with relatively low electric power due to the characteristics of radio wave propagation. Radio wave propagation characteristics of short waves are governed by extremely complex parameters such as time of day, season, sunspot number, and the like. Therefore, even if it is possible to predict the average propagation characteristic in the long term, it is difficult to predict how many watts of transmission power the communication can perform in the actual communication field. For this reason, normally, communication is performed with the maximum permitted transmission power.
しかし、このように最大の送信電力で送信すると、必要
以上の遠距離まで通信が伝播し、それだけ第三者に傍受
される危険性が高くなるという問題点があった。また必
要以上に多きな出力の電波電力を送出するため、他局に
混信を与える可能性もある。 通信を開始後に、電波電力を適度な強度に制御しても十
分な通信の秘密を保つことができない。例えば防護設備
のように通信について極度に秘密が要求されるところで
は、通信を開始したこと自体を敵国に察知されくない。
ところが通信を開始後に電波電力を制御しても、通信内
容の機密は保てるが、通信回数などの状況を知られてし
まうことになる。また好漁場を発見した漁船が近くにい
る僚船に情報を伝えようとして通信する場合などでも、
より遠くにいるライバル船は通信内容が解らなくても、
送信のあったこと自体が解ればその方向を目指して殺到
し、実質的に通信内容が洩れているのと同じ状態にな
る。 本発明はかかる欠点を解消するためになされたものであ
り、常に必要最低限の送信電力を自動的に設定して送信
することができる無線通信方式を提供することを目的と
するものである。However, such transmission with the maximum transmission power causes a problem that the communication propagates to a longer distance than necessary and the risk of being intercepted by a third party increases accordingly. Further, since radio wave power with an output larger than necessary is transmitted, there is a possibility that interference may be given to other stations. Even if the electric power of radio waves is controlled to an appropriate level after the start of communication, it is impossible to keep sufficient communication secret. For example, where protection of communication is extremely confidential, such as protective equipment, it is not possible for the enemy country to detect that communication has started.
However, even if the electric power is controlled after the communication is started, the content of the communication can be kept confidential, but the situation such as the number of times of communication will be known. In addition, even when a fishing boat that has found a good fishing ground communicates to inform a fellow ship nearby,
Rival ships farther away, even if they do not understand the communication content,
If you understand that there was a transmission, it will flood in aiming for that direction, and it will be in the same state as the communication content is actually leaked. The present invention has been made to solve the above drawbacks, and an object of the present invention is to provide a wireless communication system capable of automatically setting and transmitting the minimum required transmission power at all times.
上記課題を解決するための本発明を適用する無線通信方
式を、実施例に対応する第１図により説明する。 本発明の通信方式では、送信局と受信局ともに送受信機
を有している。同図に示すように送信局１側には、送信
電力を徐々に増加する送信電力設定手段14、送信電力設
定手段14で設定されたその時の送信電力を示すコードを
発生するコード化手段15、コード化手段15で発生したコ
ードを自局の呼び出し符号に続けて送信する送信手段11
・12・13、および受信局２の応答信号を受信しその品質
を検定する受信品質検定手段16・17を備えている。受信
局側２には、送信局１から送られたコードを解読して送
信電力値を検知する送信電力検知手段21・22・23、自局
の送信電力を送信電力検知手段21・22・23で検知した送
信電力値に一致させる電力設定手段24、および電力設定
手段24で設定された送信電力により応答信号を送信する
送信手段25・26・27を備えている。A wireless communication system to which the present invention is applied to solve the above problem will be described with reference to FIG. 1 corresponding to the embodiment. In the communication system of the present invention, both the transmitting station and the receiving station have a transceiver. As shown in the figure, on the transmitting station 1 side, transmission power setting means 14 for gradually increasing the transmission power, coding means 15 for generating a code indicating the transmission power set at that time by the transmission power setting means 14, Transmitting means 11 for transmitting the code generated by the encoding means 15 following the calling code of its own station
12 and 13 and reception quality verification means 16 and 17 for receiving the response signal of the receiving station 2 and verifying its quality. The receiving station side 2 decodes the code sent from the transmitting station 1 to detect the transmission power value, and the transmission power detecting means 21, 22, 23, and the transmission power of its own station, the transmission power detecting means 21, 22, 23. The power setting means 24 that matches the transmission power value detected in 1. and the transmission means 25, 26, and 27 that transmits a response signal with the transmission power set by the power setting means 24 are provided.
送信局１は受信局２を呼出すに際し、当初は小さい送信
電力で送信し、小さい送信電力から徐々に送信電力を増
加し、かつその時の送信電力をコード化して呼出し符号
とともに受信局２に伝送する。受信局２は呼出し符号を
受信しコードを解読して得た送信電力と等しい電力に自
局の送信電力を自動的に設定して応答する。この応答信
号を送信局１で受信して明瞭に確認されたときに送信電
力の増加を停止する。そのため時刻、季節、太陽黒点数
等により時々刻々と電波伝播特性が変化する中でも、通
信開始当初から最小出力の電力で通信できるようにな
り、第三者は通信内容を知ることができないばかりでな
く、通信を開始したこと自体に気付くこともない。When calling the receiving station 2, the transmitting station 1 initially transmits with a low transmission power, gradually increases the transmission power from a low transmission power, and codes the transmission power at that time and transmits it to the receiving station 2 together with the calling code. . The receiving station 2 automatically sets its own transmission power to a power equal to the transmission power obtained by receiving the calling code and decoding the code and responding. When this response signal is received by the transmitting station 1 and is clearly confirmed, the increase of the transmission power is stopped. Therefore, even if the radio wave propagation characteristics change momentarily due to time, season, sunspot number, etc., it becomes possible to communicate with the minimum output power from the beginning of communication, and not only the third party can not know the contents of communication. , You do not even notice that you started communication.
以下、本発明の実施例を詳細に説明する。 第１図は本発明の無線通信方式を実施するための系統図
の一例である。 同図の１は送信局、２は受信局である。11は送信局１の
変調回路、12は可変減衰器、13は送信用増幅器であり、
変調回路11と可変減衰器12および送信用増幅器13で送信
局１の送信部を構成している。14は送信電力を徐々に増
加して設定する送信電力設定回路、15は設定された送信
電力値を示すコードを発生するコード化回路である。16
は受信用増幅器、17は受信用増幅器16で受信した応答信
号の品質を検定する受信品質検定回路である。 21は受信局２に設けられた受信用増幅器、22は復調回
路、23はデコーダ、24は受信局２の送信電力を設定する
電力設定回路である。25は変調回路、26は可変減衰器、
27は送信用増幅器であり、変調回路25と可変減衰器26お
よび送信用増幅器27で受信局２の送信部を構成してい
る。 上記のように構成された送受信系で、送信局１から受信
局２に通信を行なう場合の動作を第２図に示すフローチ
ャートを参照して説明する。尚、このフローチャートで
ステップ101から105までは送信局１における動作、ステ
ップ201から203までは受信局２における動作である。 送信開始に際して、送信局１の送信電力設定回路14は送
信局１の送信電力が予め定められた充分小さい値になる
ように設定し、可変減衰器13を調定する。それと同時
に、その時の設定電力値をコード化回路15に伝送する。
コード化回路15は予め定められた規約によって伝送され
た設定電力値をコード化し、変調回路11に送る。 変調回路11は通常の通信手順通り、呼出信号と設定電力
値のコードを可変減衰器12の送信用増幅器13を通して、
最小送信電力で受信局２に送信する（ステップ101）。
受信局２が最小送信電力で送信された呼出信号と設定電
力値のコードを受信できないときは（ステップ201）、
受信局２からは応答がされない（ステップ202）。一
方、送信局１は受信局２から応答信号が送られるのを一
定時間待つ（ステップ102）。一定時間経過後応答信号
の有無を判断し、そこに応答信号が送られていないとき
は（ステップ103）、送信電力設定回路14であらかじめ
定められた一定の比で送信電力を増加して設定し、呼出
信号と増加した設定電力値のコードを、増加した送信電
力で受信局２に送信する（ステップ104）、この送信を
受信局２が受信できないときは（ステップ201）、受信
局２からは応答がされない（ステップ202）。そこで、
送信局１は受信局２から応答信号が送られるのを一定時
間待つ（ステップ102）。一定時間経過後応答信号の有
無を判断し、そこで応答信号が送られていないときは
（ステップ103）、再び送信電力設定回路14で一定の比
で送信電力を増加して設定し、呼出信号と増加した設定
電力値のコードを増加した送信電力で受信局２に送信す
る（ステップ104）。 この処理を繰り返し行ない、受信局２の受信用増幅器21
が送信局１からの呼出信号と設定電力値のコードを受信
すると、受信局２の復調回路22でが受信信号を復調し
て、デコーダ23に送る。デコーダ23は送信されたコード
から伝送された送信電力値を復号し、電力設定回路24に
送る。電力設定回路24は送られた送信電力値に一致する
ように送信電力を設定し、可変減衰器26を調定して送信
用増幅器27から応答信号を送信する（ステップ203）。 送信局１の受信用増幅器16はこの応答信号を受信する
と、応答信号を受信品質検定回路17に送る。受信品質検
定回路17は応答信号の受信品質を検定する（ステップ10
5）。この受信品質はデジタル送信を行なう通信系であ
ればビット誤り率、アナログ伝送を行なう通信系であれ
ばS/N比等で検定される。これらはいずれも自動計測で
きる通常の計測器が使用される。 受信品質検定回路17の検定結果が通信を維持できる品質
できないときは、再び送信電力設定回路14で一定の比で
送信電力を増加して設定し、呼出信号と増加した設定電
力値のコードを増加した送信電力で受信局２に送信する
（ステップ104）。 受信品質検定回路17の検定結果が通信を維持できる品質
であると、受信品質検定回路17は送信電力設定回路14に
電力設定停止信号を送って送信電力をこの状態で停止さ
せる。その後、送信局１と受信局２は通常の通信状態に
入り、相互に通信を行なう。Hereinafter, examples of the present invention will be described in detail. FIG. 1 is an example of a system diagram for implementing the wireless communication system of the present invention. In the figure, 1 is a transmitting station and 2 is a receiving station. 11 is a modulation circuit of the transmission station 1, 12 is a variable attenuator, 13 is a transmission amplifier,
The modulation circuit 11, the variable attenuator 12 and the transmission amplifier 13 constitute a transmission section of the transmission station 1. Reference numeral 14 is a transmission power setting circuit for gradually increasing and setting the transmission power, and 15 is a coding circuit for generating a code indicating the set transmission power value. 16
Is a reception amplifier, and 17 is a reception quality inspection circuit for inspecting the quality of the response signal received by the reception amplifier 16. Reference numeral 21 is a receiving amplifier provided in the receiving station 2, 22 is a demodulating circuit, 23 is a decoder, and 24 is a power setting circuit for setting the transmission power of the receiving station 2. 25 is a modulation circuit, 26 is a variable attenuator,
Reference numeral 27 denotes a transmission amplifier, and the modulation circuit 25, the variable attenuator 26, and the transmission amplifier 27 constitute a transmission section of the reception station 2. The operation of the transmission / reception system configured as described above when communication is performed from the transmission station 1 to the reception station 2 will be described with reference to the flowchart shown in FIG. In this flowchart, steps 101 to 105 are operations in the transmitting station 1, and steps 201 to 203 are operations in the receiving station 2. At the start of transmission, the transmission power setting circuit 14 of the transmission station 1 sets the transmission power of the transmission station 1 to a predetermined sufficiently small value, and adjusts the variable attenuator 13. At the same time, the set power value at that time is transmitted to the coding circuit 15.
The coding circuit 15 codes the set power value transmitted according to a predetermined rule and sends it to the modulation circuit 11. The modulation circuit 11 follows the normal communication procedure, the ringing signal and the code of the set power value through the transmission amplifier 13 of the variable attenuator 12,
It transmits to the receiving station 2 with the minimum transmission power (step 101).
When the receiving station 2 cannot receive the ringing signal transmitted with the minimum transmission power and the code of the set power value (step 201),
No response is received from the receiving station 2 (step 202). On the other hand, the transmitting station 1 waits for a certain period of time until the receiving station 2 sends a response signal (step 102). After a certain period of time, the presence or absence of a response signal is judged, and when the response signal is not sent to it (step 103), the transmission power is set by the transmission power setting circuit 14 by increasing the transmission power at a predetermined ratio. , The code of the ringing signal and the increased set power value is transmitted to the receiving station 2 with the increased transmission power (step 104). When the receiving station 2 cannot receive this transmission (step 201), the receiving station 2 No response is received (step 202). Therefore,
The transmitting station 1 waits for a fixed time until a response signal is sent from the receiving station 2 (step 102). After a certain period of time, it is determined whether or not there is a response signal, and when the response signal is not sent there (step 103), the transmission power setting circuit 14 again increases and sets the transmission power at a constant ratio to set the ringing signal. The code of the increased set power value is transmitted to the receiving station 2 with the increased transmission power (step 104). By repeating this processing, the receiving amplifier 21 of the receiving station 2
When the receiver receives the ringing signal and the code of the set power value from the transmitting station 1, the demodulation circuit 22 of the receiving station 2 demodulates the received signal and sends it to the decoder 23. The decoder 23 decodes the transmission power value transmitted from the transmitted code and sends it to the power setting circuit 24. The power setting circuit 24 sets the transmission power so as to match the transmitted transmission power value, adjusts the variable attenuator 26, and transmits the response signal from the transmission amplifier 27 (step 203). Upon receiving this response signal, the reception amplifier 16 of the transmission station 1 sends the response signal to the reception quality inspection circuit 17. The reception quality verification circuit 17 verifies the reception quality of the response signal (step 10
Five). This reception quality is verified by a bit error rate in a communication system that performs digital transmission, and an S / N ratio in a communication system that performs analog transmission. For each of these, a normal measuring instrument that can automatically measure is used. If the verification result of the reception quality verification circuit 17 cannot maintain communication quality, the transmission power setting circuit 14 again increases the transmission power at a constant ratio to set the ringing signal and the code of the increased set power value. The transmitted power is transmitted to the receiving station 2 (step 104). If the verification result of the reception quality verification circuit 17 indicates that communication can be maintained, the reception quality verification circuit 17 sends a power setting stop signal to the transmission power setting circuit 14 to stop the transmission power in this state. After that, the transmitting station 1 and the receiving station 2 enter a normal communication state and communicate with each other.
以上説明したように本発明の無線通信方式は、送信局が
相手局を呼出すに際し、小さい送信電力から徐々に送信
電力を増加し、かつその時の送信電力をコード化して呼
出し符号とともに送信局に伝送し、受信局は呼出しを受
信しコードを解読して得た送信電力と等しい電力に自局
の送信電力を自動的に設定して応答し、この応答信号を
送信局で受信して明瞭に確認されたときに送信電力の増
加を停止するようにしたので、通信を行なおうとする時
点で必要最小限の送信電力で通信を行なうことができ
る。 したがって、短波通信においても不要な遠距離に電波が
到達して第三者に傍受される危険性を減らすことができ
る。送信局が相手局を呼出す当初から小さい送信電力で
しか通信しないので、第三者には通信内容を傍受されな
いだけではなく、通信を開始したこと自体も気取られる
ことがない。例えば、防衛設備からの送信回数などを敵
国に察知される恐れもなくなる。また好漁場を発見した
漁船が近くにいる僚船に情報を伝えようして送信する場
合などでも、より遠くにいるライバル船に通信を気付か
れて、好漁場に多くの船が殺到して混乱するという事態
が避けられる。 また必要以上に大きな電波電力を送出しないですみ、他
局に与える混信を減らすことができる。そのため電波の
有効利用を図ることができとともに、省エネルギーの効
果も期待できる。As described above, in the wireless communication system of the present invention, when the transmitting station calls the partner station, the transmission power is gradually increased from a small transmission power, and the transmission power at that time is coded and transmitted to the transmitting station together with the calling code. Then, the receiving station responds by automatically setting its own transmission power to a power equal to the transmission power obtained by receiving the call and decoding the code, and confirming clearly by receiving this response signal at the transmission station. Since the increase of the transmission power is stopped when the communication is performed, the communication can be performed with the minimum required transmission power at the time of attempting the communication. Therefore, even in short-wave communication, it is possible to reduce the risk of radio waves reaching an unnecessary long distance and being intercepted by a third party. Since the transmitting station communicates only with a small transmission power from the beginning of calling the partner station, not only the third party can not intercept the communication content, but also the fact that the communication has started is not distracting. For example, the number of transmissions from the defense equipment will not be detected by the enemy country. Also, even when a fishing boat that has found a good fishing ground sends information to a nearby fellow ship, a rival ship located further away notices the communication and many ships are flooded into the good fishing ground and become confused. The situation can be avoided. In addition, it is possible to reduce the interference given to other stations without transmitting too much radio wave power. Therefore, the effective use of radio waves can be achieved, and the effect of energy saving can be expected.
第１図は本発明の無線通信方式を実施するための系統図
の一例、第２図は系統の動作を示すフローチャートであ
る。 １……送信局、２……受信局 11……変調回路、12……可変減衰器 13……送信用増幅器、14……送信電力設定回路 15……コード化回路、16……受信用増幅器 17……品質検定回路、21……受信用増幅器 22……復調回路、23……デコーダ 24……電力設定回路、25……変調回路 26……可変減衰器、27……送信用増幅器 101〜105……送信局１における動作 201〜203……受信局２における動作FIG. 1 is an example of a system diagram for implementing the wireless communication system of the present invention, and FIG. 2 is a flowchart showing the operation of the system. 1 ... Transmission station, 2 ... Reception station 11 ... Modulation circuit, 12 ... Variable attenuator 13 ... Transmission amplifier, 14 ... Transmission power setting circuit 15 ... Coding circuit, 16 ... Reception amplifier 17 …… Quality test circuit, 21 …… Reception amplifier 22 …… Demodulation circuit, 23 …… Decoder 24 …… Power setting circuit, 25 …… Modulation circuit 26 …… Variable attenuator, 27 …… Transmission amplifier 101- 105 ...... Operation in transmitting station 201-203 ...... Operation in receiving station 2
Claims (1)
信系において、 送信局側には、送信電力を徐々に増加する送信電力設定
手段、該送信電力設定手段で設定されたその時の送信電
力を示すコードを発生するコード化手段、該コード化手
段で発生したコードを自局の呼び出し符号に続けて送信
する送信手段、および受信局の応答信号を受信しその品
質を検定する受信品質検定手段を備え、 受信局側には、送信局から送られたコードを解読して送
信電力値を検知する送信電力検知手段、自局の送信電力
を上記送信電力検知手段で検知した送信電力値に一致さ
せる電力設定手段、および該電力設定手段で設定された
送信電力により応答信号を送信する送信手段を備え、 送信局は相手局を呼出すに際し、当初は小さい送信電力
で送信し、受信品質検定手段で受信局からの明瞭な応答
を確認するまで送信電力設定手段で小さい送信電力から
徐々に送信電力を増加し、かつその時の送信電力をコー
ド化手段でコード化して呼出し符号とともに送信手段で
伝送し、 受信局は呼出しを受信し、送信電力検知手段でコードを
解読して得た送信電力と等しい電力に自局の送信電力を
電力設定手段で自動的に設定して送信手段で応答するこ
とを特徴とする無線通信方式。1. In a communication system in which both the transmitting station and the receiving station have a transceiver, the transmitting station side has a transmitting power setting means for gradually increasing the transmitting power, and the transmitting power at that time set by the transmitting power setting means. Coding means for generating a code indicating the above, a transmitting means for transmitting the code generated by the coding means following the calling code of its own station, and a reception quality verification means for receiving the response signal of the receiving station and verifying its quality. On the receiving station side, the transmission power detection means that decodes the code sent from the transmission station and detects the transmission power value, the transmission power of the own station matches the transmission power value detected by the transmission power detection means. And a transmitting unit that transmits a response signal with the transmission power set by the power setting unit. When the transmitting station calls the partner station, the transmitting station initially transmits with a small transmission power and receives the received signal. The transmission power is gradually increased from the small transmission power by the transmission power setting means until the clear response from the receiving station is confirmed by the verification means, and the transmission power at that time is coded by the coding means and is transmitted by the transmission means together with the calling code. The receiving station receives the call, the transmission power of the local station is automatically set to the same power as the transmission power obtained by decoding the code by the transmission power detection means, and the transmission means responds. A wireless communication system characterized in that
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1111795A JPH06105901B2 (en) | 1989-04-28 | 1989-04-28 | Wireless communication system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1111795A JPH06105901B2 (en) | 1989-04-28 | 1989-04-28 | Wireless communication system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH02288745A JPH02288745A (en) | 1990-11-28 |
| JPH06105901B2 true JPH06105901B2 (en) | 1994-12-21 |
Family
ID=14570347
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1111795A Expired - Lifetime JPH06105901B2 (en) | 1989-04-28 | 1989-04-28 | Wireless communication system |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH06105901B2 (en) |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0695651B2 (en) * | 1985-08-01 | 1994-11-24 | 日本電気株式会社 | Wireless communication device |
-
1989
- 1989-04-28 JP JP1111795A patent/JPH06105901B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH02288745A (en) | 1990-11-28 |
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