JPS6175634A - Radio relay system - Google Patents

Abstract

PURPOSE:To eliminate the interruption of relaying from the start of a master station to the start of the transmitter of a relay station by starting temporarily the transmitter only with a noise detection output,interrupting the relaying when no tone reception is confirmed and keeping the relaying when confirmed. CONSTITUTION:A timer circuit 6 is started by the output signal A of a noise detection circuit 1 to output a signal D. The time width t2 of a signal D is set slightly larger than a time delay t1 produced by a narrow band filter 2. Since the transmitter Tx is started successively from a reception wave input point of time, the delay in the relay time by the delay time t1 is eliminated. When the reception wave input exists and no tone signal is received (figure c), since the output signal B of a tone detection circuit 3 does not rise, the signal C falls down after the time t2, resulting that the relaying is interrupted.

Description

【発明の詳細な説明】 （技術分野） この発明は地方自治体の市町村に設置される同報無線又
は防災行政無線における無線中継所の無線機の電波送出
制御方法に関するものである。DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a method for controlling the transmission of radio waves of radio equipment at a radio relay station in broadcast radio or disaster prevention administrative radio installed in municipalities of local governments.

（従来技術とその問題点） 第２図は従来例を示し、第２図ａは無線中継所の系統図
であって、　Ｒｘは無線受信機、　Ｔｘは無線送信機＋
　ｆＩは受信電波＋　ｆ２は送信電波、１は雑音検出回
路、２はトーン検出用狭帯域フィルタ、３はトーン検出
回路、４はＡＮＤ回路、５は信号中継線であり、第２図
すは第１図ａの各部の出力信号のタイミングである。親
局からのトーン信号及び音声信号で変調された電波ｆ、
が着信すると受信機Ｒｘを介した雑音検出回路１が雑音
が無くなったことを検出して信号イを出力する。また狭
帯域フィルタ２によりトーン信号を抽出し、−一一一←
セ＝トーン検出回路３で検波して信号口を出力する。Ａ
ＮＤ　回路４で信号４９口の出力が有ることの条件で信
号ハを出力する。信号ハの出力により送信機Ｔｘを起動
させ、信号中継線５がそのまま送信（−５Ｔｘの変調入
力に接続しであるので通信電波「２を出力する。この場
合狭帯域フィルタ２は遅れ時間を生じるため、信号イの
出力に対し第２図すに示すごとく時間ｔ１だけ信号口の
出力が遅れる。信号イ２口の出力があることが中継の条
件であるので、送信機Ｔｘの電波送出は電波着信からｔ
、たけ遅れることとなる。このｔｌの値は狭帯域フイル
り２の帯域幅に関連するが一般的には１〜２秒を要する
。このため親局から送信される音声信号が、親局起動か
ら中継所送信機起動までの時間、即ちｔｌだげの間途切
れるという不具合を有している。(Prior art and its problems) Figure 2 shows a conventional example, and Figure 2a is a system diagram of a wireless relay station, where Rx is a wireless receiver, and Tx is a wireless transmitter +
fI is a received radio wave + f2 is a transmitted radio wave, 1 is a noise detection circuit, 2 is a narrowband filter for tone detection, 3 is a tone detection circuit, 4 is an AND circuit, 5 is a signal relay line, and Figure 2 shows the This is the timing of the output signals of each part in FIG. 1a. Radio waves f modulated with tone signals and audio signals from the master station,
When a call arrives, the noise detection circuit 1 via the receiver Rx detects that there is no noise and outputs a signal A. Also, the tone signal is extracted by the narrow band filter 2, -111←
The set tone detection circuit 3 detects the signal and outputs the signal. A
ND circuit 4 outputs signal C on the condition that 49 signals are output. The transmitter Tx is activated by the output of the signal C, and the signal relay line 5 transmits as it is (connected to the modulation input of -5Tx, so it outputs the communication radio wave ``2''. In this case, the narrow band filter 2 causes a delay time. Therefore, the output of the signal port is delayed by time t1 with respect to the output of signal A, as shown in Figure 2.Since the condition for relay is that there are two outputs of signal A, the radio wave transmission from the transmitter Tx is delayed by the time t1 as shown in Figure 2. t from incoming call
, there will be a huge delay. The value of tl is related to the bandwidth of the narrowband film 2, but typically takes 1 to 2 seconds. For this reason, there is a problem in that the audio signal transmitted from the master station is interrupted during the time from activation of the master station to activation of the relay station transmitter, that is, tl.

（目的） この発明はこの欠点を除去するため、雑音検出出力のみ
によって一時的に送信機を起動しておき。(Purpose) In order to eliminate this drawback, the present invention temporarily activates the transmitter only by the noise detection output.

トーン受信が確認されなげれば中継を断とし、トーン受
信が確認されれば中継を継続させて前記不具合を無くし
たものである。If the tone reception is not confirmed, the relay is cut off, and if the tone reception is confirmed, the relay is continued, thereby eliminating the above-mentioned problem.

（実施例） 以下この発明の実施例を第１図により説明する。(Example) An embodiment of the present invention will be described below with reference to FIG.

第１図ａは無線中継所の系統図であって、Ｔｘ、Ｒｘ。FIG. 1a is a system diagram of a wireless relay station, including Tx and Rx.

ｆ、、ｆ２１〜５．イ〜・・は第１図と同一物を示し。f,, f21~5. A... indicates the same thing as in Fig. 1.

６は雑音検出回路１の出力信号イにより起動するタイマ
回路、二はタイマ回路６の出力信号、７は信号二とＡＮ
Ｄ回路４の出力との和をとるＯＲ回路である。第２図す
は正規な中継の場合における第１図ａの各部の出力信号
のタイミングである。6 is a timer circuit activated by the output signal A of the noise detection circuit 1, 2 is the output signal of the timer circuit 6, and 7 is the signal 2 and AN
This is an OR circuit that calculates the sum with the output of the D circuit 4. FIG. 2 shows the timing of output signals from each section in FIG. 1a in the case of regular relay.

タイマ回路６の出力信号二の時間幅ｔ２は狭帯域フィル
タ２により生ずる時間遅れｔｌより僅かに大きな値に設
定する。受信機Ｒｘに受信波ｆ１が入ると信号イか立上
り、同時に信号二が１２の時間幅だけ立ち上がる。また
信号二と同時にＯＲ回路７を介し　　。The time width t2 of the output signal 2 of the timer circuit 6 is set to a value slightly larger than the time delay tl caused by the narrowband filter 2. When the received wave f1 enters the receiver Rx, the signal A rises, and at the same time, the signal 2 rises for a time width of 12. Also, the signal 2 is passed through the OR circuit 7 at the same time.

て信号・・が立上がる。ｔ１経過後信号口が立上るので
、ｔ２経過後信号二が立下がっても信号ノ・は立上がり
っばなしになるので、受信波入力時点から継続して送信
機Ｔｘが起動するため、狭帯域フィルタ２の遅れ時間１
．による中継時間の遅れは解消される。第２図Ｃは無線
周波数受信波入力だけがあり。The signal... goes up. Since the signal opening rises after t1 has elapsed, even if signal 2 falls after t2 elapses, the signal no. will continue to rise, so the transmitter Tx will continue to start from the point of input of the received wave, so the narrow band filter 2 delay time 1
．． This eliminates the delay in relay time due to Figure 2C has only the radio frequency reception wave input.

トーン信号が受信されない場合の各部の出力信号のタイ
ミングを示し、トーン検出回路３の出力信号口が立上が
らないため信号ノ・はｔ２経過後立下り。This shows the timing of the output signals of each section when a tone signal is not received. Since the output signal port of the tone detection circuit 3 does not rise, the signal falls after t2.

結果として中継が断となる。ここで同一受信周波数を持
つ他局からの着信時にはｔ２の時間幅だけ混信となるが
９本実施例においては固定された親局及び中継所を想定
しているので、他局からの入力電波は親局からの入力電
波に比べて低い値になる。As a result, the relay is interrupted. Here, when a call arrives from another station with the same reception frequency, there will be interference for a time width of t2, but in this example, a fixed master station and relay station are assumed, so the input radio waves from other stations will be The value will be lower than the input radio waves from the master station.

従って雑音検出回路のしきい値をこの中間に設定するこ
とにより、他局との混信を回避することができる。Therefore, by setting the threshold of the noise detection circuit to a value in the middle, interference with other stations can be avoided.

（効果） この発明による無線中継方式は、トーン信号付無線中継
方式において、トーン信号検出時間により生じる中継途
切れがないので１通話冒頭の途切れを解消することがで
きる。(Effects) The wireless relay system according to the present invention eliminates the interruption at the beginning of one call because there is no relay interruption caused by the tone signal detection time in the wireless relay system with tone signal.

【図面の簡単な説明】[Brief explanation of the drawing]

第１図は本発明の実施例を示し、ａは無線中継所の系統
図、ｂは正規な中継時の各部出力信号のタイミング、Ｃ
はトーン信号が受信されない場合の各部出力信号のタイ
ミング、第２図は従来例を示し、ａは無線中継所の系統
図、ｂは中継時の各部出力信号のタイミングである。 ＲＸ：無線受信機、Ｔｘ：無線送信機、１：雑音検出回
路、２：狭帯域フィルタ、３：トーン検出回路、４：Ａ
ＮＤ回路、５：信号中継線、６：タイマ回路、７：ＯＲ
回路。 第２図 （ａ）　　　　　　（ｂ）FIG. 1 shows an embodiment of the present invention, in which a is a system diagram of a wireless relay station, b is the timing of output signals of each part during regular relaying, and C is a system diagram of a wireless relay station.
2 shows a conventional example, a is a system diagram of a wireless relay station, and b is a timing of output signals of each part when a tone signal is not received. RX: Radio receiver, Tx: Radio transmitter, 1: Noise detection circuit, 2: Narrowband filter, 3: Tone detection circuit, 4: A
ND circuit, 5: Signal relay line, 6: Timer circuit, 7: OR
circuit. Figure 2 (a) (b)

Claims (1)

【特許請求の範囲】[Claims] 親局から多数の子局に通報する同報無線又は防災行政無
線における無線中継所の無線機の送信電波送出を、通話
帯域内の特定周波数即ちトーン信号の出力と、無線周波
数受信の有無を検知するノイズスケルチの出力との和で
制御する無線中継方式において、前記両者の出力和が成
立するまでの時間差に見合ったある一定時間、前記無線
機の送信機を起動させておくことを特徴とする無線中継
方式。Detects the output of a specific frequency in the communication band, that is, the tone signal, and the presence or absence of radio frequency reception in the transmission radio waves of the radio equipment of the radio relay station in the broadcast radio or disaster prevention administrative radio that reports from the master station to a large number of slave stations. In a radio relay system controlled by the sum of the output of the noise squelch, the transmitter of the radio is activated for a certain period of time commensurate with the time difference until the sum of the two outputs is established. Relay method.