JPH047926A - Source station identification method and device - Google Patents

Abstract

PURPOSE:To monitor plural caller stations and to identify them by outputting a voice signal only when a tone signal from a desired caller station is detected and monitoring and displaying which station is making a call. CONSTITUTION:A tone signal generator 3 outputs tone signals S1, S2... of a voice out-band frequency specified to a system of a reception station R and the tone signals S1, S2... are inputted to a transmission section 5 while being superimposed on a voice signal S outputted from a band pass filter 2 at an adder 4 and sent from the transmission section 5. On the other hand, a demodulation signal is inputted to plural detection circuits 12, 12a... and inputted to a hand pass filter 9 of a detection circuit having a frequency coincident with the voice out-band frequency specified by the generator 3, the tone signal passes through the filter and detected by a detection circuit 10. The detection signal is inputted to a controller 13, which displays which caller station T makes a call and a voice output control section 11 is controlled by a control signal outputted from the controller 13 and the voice signal S is outputted from the control section 11.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method and apparatus for identifying a transmitting station in a communication system in which a plurality of stations transmit and receive signals using the same carrier frequency.

[Prior art]

Conventionally, the method of selective calling when multiple wireless stations share the same carrier frequency involves transmitting a tone signal superimposed outside the voice band, detecting this tone signal, and transmitting it to the receiver. Tone squelch is known in which only signals from desired stations are received by controlling audio output.

FIG. 1 shows a system diagram of a transmitter installed in a conventional transmitting station and that of the present invention, and FIG. 3 shows a system diagram of a receiver installed in a conventional receiving station.

In Fig. 1, the audio signal S output from a microphone etc. is
The audio amplifier 1 amplifies the signal to a predetermined level, and the bandpass filter 2 removes unnecessary components.

The tone signal generator 3 at a frequency outside the voice band sends out a specific tone signal S, during transmission. The tone frequency is set to a frequency outside the audio band that is previously matched with that of the other party's receiving station. The tone signal S1 is superimposed on the audio signal S output from the band switch 2 by an adder 4, modulated by a transmitting section 5, amplified at high frequency, and emitted as a radio wave from a transmitting antenna 14.

In the receiver shown in FIG. 3, radio waves are received by the receiving antenna 15, amplified and demodulated by the receiving section 6. The tone signal Sl is removed from this demodulated signal by a high-pass filter 7 to obtain an audio signal S, which is then amplified by an audio amplifier 8 to a predetermined level.

On the other hand, a part of the demodulated signal is input to a bandpass filter 9 for tone detection. When the tone frequency on the transmitting side and the pass frequency of the bandpass filter 9 match, the signal is input to the detector 10, the detection output controls the audio output control switch 11, and the audio signal S is outputted from this.

[Problem to be solved by the invention]

With such a conventional tone squelch circuit, when a plurality of stations share the same carrier frequency, the receiving station cannot know which station is in the process of making a call. Therefore, there is a problem in that it is difficult to monitor the call status or interrupt a station in progress to monitor or make a call.

[Means to solve the problem]

In order to solve the above-mentioned problems, the method of the present invention is aimed at, in a communication system in which a plurality of stations transmit and receive signals using the same carrier frequency, as shown in Figures 1 and 2, each of the plurality of transmitting stations T The signal S includes a tone signal S1 of a frequency outside the voice band.
Transmission is performed by superimposing S2..., and the receiving station R is
Detection circuits 12 = 12a for detecting tone signals S1, S2, etc. from each transmitting station T are provided as many as the number of stations in the system, and detecting the frequency outside the voice band from the desired transmitting station T. It is characterized by outputting the audio signal S only when a tone signal is detected, and monitoring and displaying which station is transmitting based on the frequency outside the audio band of the detected tone signal.

In order to solve the same problem, the device of the present invention has a communication system in which a plurality of stations transmit and receive signals using the same carrier frequency as shown in Figs. bandpass filter 2 that removes unnecessary components of
A tone signal generator 3 generates tone signals S, , S, . . . of frequencies outside the audio band specified corresponding to the system of It consists of an adder 4 that is superimposed on the output S of the bandpass filter 2, and a transmitter 5 that transmits the output of the adder 4, and the receiving station R receives the transmission output of the transmitter 5 of each transmitting station T and demodulates it. a high-pass filter 7 that inputs the demodulated signal output from the receiver 6 and removes the tone signals S1-S2, and an audio signal S output from the high-pass filter 7. The audio output control section 11 inputs the demodulated signal and outputs the tone signal S1. of the specified audio band frequency.
A plurality of band filters 99a passing through S2...
...and these bandpass filters 9, 9a-...
Detector 10 inputs the output of... and outputs a detection signal
．． 10a..., detection circuits 12 provided as many as the number of stations in the system = 12a..., and among these detection circuits 12.12a..., the desired one ．．
a tone signal S of a frequency outside the voice band from a transmitting station T,
, S2 .
It is composed of a controller 13 that displays S2...

[For production]

At a plurality of transmitting stations T, the audio signals S are input to a bandpass filter 2 to remove unnecessary components. Tone signal generator 3
corresponds to the system of the receiving station R. The tone signal S7. of the frequency outside the voice band specified in 1.7. -82...... is output,
This tone signal S1. S2... is superimposed on the audio signal S output from the bandpass filter 2 by the adder 4, and is input to the transmitter 5 and transmitted.

At the receiving station R, the transmission output of the transmitting section 5 is received and demodulated by the receiving section 5, and this demodulated signal is input to the high-pass filter 7 to remove the tone signals S1-S2. The audio signal S is output and input to the audio output control section H.

On the other hand, the demodulated signal is transmitted to a plurality of detection circuits 12-12a--...
・ Among these, the tone signal is inputted to the bandpass filter of the detection circuit of the frequency matching the voice band frequency specified by the tone signal generator 3, and is detected by the detector. be done. This detection signal is input to the controller 13, and this controller 13 displays which transmitting station T is in the process of making a call (calling).
The audio output controller 11 is controlled by the control signal output from the audio output controller 3, and the audio signal S is output from the audio output controller 11.

〔Example〕

The present invention will be explained in detail below with reference to the drawings.

As the transmitter installed in the transmitting station of the present invention, the transmitter shown in the first diagram can be used. In Figure 1, 1 is an audio amplifier that amplifies the audio signal S output from a microphone etc. to a predetermined level, 2 is a bandpass filter that removes unnecessary components contained in the audio signal S, and 3 is a system of the receiving station R of the other party in advance. A tone signal generator that generates a tone signal set to a frequency outside the audio band that matches the frequency of the voice signal, and sends out the tone signal specified at the time of transmission. 4 is a tone signal S, , S2 or S3 of a specific audio band frequency outputted from this tone signal generator 3 to the audio signal S outputted from the bandpass filter 2.
5 is a transmitting section that modulates the output of this adder 4 and amplifies it at high frequency. 14 is a transmitting antenna that emits the output of this transmitting section 5 as a radio wave.

FIG. 2 is a system diagram of a receiver installed in the receiving station of the present invention, where 15 is a receiving antenna that receives radio waves, 6 is a receiving section that amplifies and demodulates the received radio waves, and 7 is demodulated by the receiving section 6. 8 is a high-pass filter that inputs the signal, removes the tone signal 5182 or S3, and outputs the audio signal S; 8 is an audio amplifier that amplifies the audio signal S output from the high-pass filter 7 to a predetermined 17 bells; 11; is an audio output control switch that inputs the output of this audio amplifier 8.

12=detection circuits 12a and 12b each input a part of the demodulated signal and output a detection signal, and are provided as many as the number of stations in the system. 9=9a, 9b are three bandpass filters that each input a part of the demodulated signal and pass the tone signal S, -S3 of a frequency outside the audio band specified by the tone signal generator 3 of the transmitter; 10=10a; 10b is a detector which inputs the outputs of these bandpass filters 9=9a and 9b and outputs a detection signal, and includes three bandpass filters 9.
9a=9b and the detectors 10, ], Oa, and 10b constitute detection circuits 12.12a and 12b, respectively.

13 is one of these detection circuits 12.12a, 12b, which activates the audio output control switch 11 with this detection signal only when it detects a tone signal 81 to S3 of a specified audio band frequency from a desired transmitting station T. This is a controller that selects to turn on the tone signal S, outputs the audio signal S, and displays the tone signals S and S3.

In the above configuration, the first transmitting station T among the three transmitting stations
The operation of this embodiment will be described when the tone signal generator 3 converts the tone signal having a frequency outside the voice band (the tone signal having the frequency on the transmitting side) into the tone signal S1 specified at the first frequency outside the voice band.

The audio signal S output from the microphone, etc. of the first transmitting station T is input to the audio amplifier 1 and amplified to a predetermined level.This amplified signal is input to the bandpass filter 2 to remove unnecessary components, and is output from this. The tone signal S having a frequency outside the first audio band is output from the tone signal generator 3 to the audio signal S.
t is superimposed by the adder 4, inputted to the transmitter 5, modulated, high-frequency amplified, and fed to the transmitting antenna 14,
From this, it is emitted as radio waves.

This radio wave is received by the receiving antenna 15 of the receiving station R, high-frequency amplified and demodulated by the receiving section 5, and this demodulated signal is input to the high-pass filter 7, where the tone signal S1 is removed, and an audio signal is output from this. and is input to the audio output control switch 11.

On the other hand, a part of the demodulated signal is sent to three detection circuits 12.12a.

12b, among which tone signal generator 3
The tone signal S1 is inputted to the bandpass filter 9 of the detection circuit 12 for a frequency matching the first audio band frequency specified in , and is passed through, and detected by the detector 10.

This detection signal is input to the controller 13.
is the tone signal S1 of the frequency outside the first audio band, and the first
The display 17 indicates that the transmitting station T is in the process of making a call (calling), and the audio output control switch 11 is turned on by a control signal output from the controller 13, that is, a tone signal S1 having a frequency outside the first audio band. By selecting this with the selection switch 16, the transmitting station T using the tone signal S1 of the frequency outside the first audio band can be monitored and identified.

Even when the tone signal generator 3 of the second or third transmitting station T converts the tone signal of the frequency outside the voice band into a tone signal S2 or S3 specified as the second or third frequency outside the voice band, reception is performed in the same manner as above. Station R detection circuit 12a or 12b
The tone signal S of the second or third audio band frequency is
2 or S3 is detected, the controller 13 selects the second or third
The display 16 indicates that the transmitting station T is in the process of making a call (calling), and this detection signal causes the controller 13 to use the tone signal S2 or S3 of the frequency outside the second or third audio band. It is possible to monitor by selecting the second or third transmitting station T with the selection switch 17,
Multiple originating stations T can be identified.

In this way, it is possible to display which station among the first to third transmitting stations T is transmitting, and it is also possible to monitor and identify the plurality of receiving stations. Therefore, it is possible to monitor the call status or to interrupt the system in progress to monitor or make a call.

〔Effect of the invention〕

As described above, according to the present invention, in a communication system in which a plurality of stations transmit and receive signals using the same carrier wave frequency, it is possible to determine which station among the plurality of transmitting stations T is currently transmitting (calling). can be displayed and multiple transmitting stations can be monitored and identified.

Therefore, it is possible to monitor the call status or to interrupt the system in progress to monitor or make a call.

[Brief explanation of the drawing]

Fig. 1 is a system diagram of a transmitter installed in a conventional and inventive transmitting station, Fig. 2 is a system diagram of a receiver installed in a receiving station of the invention, and Fig. 3 is a system diagram of a receiver installed in a conventional receiving station. FIG. 2 is a system diagram of a receiver. 2...Band filter, 3...Tone signal generator, 4...Adder, 5...Transmitter, 6...Receiver Part, 7...High-pass filter, 9.9a...Band filter, 1010a.
......Detector, 11-...Audio output control section (
switch), 12.12a...detection circuit, 1
3...Controller, 14...Transmitting antenna, 15...Receiving antenna, 5IS2...
・Tone signal, S...Audio signal, T...
- Sending station, R... Receiving station, 16... Display, 17... Selection switch.

Claims (2)

[Claims] (1) In a communication system in which multiple stations transmit and receive signals using the same carrier frequency, each of the multiple transmitting stations (T) uses a tone signal (
S_1, S_2...) are superimposed and transmitted,
The receiving station (R) receives the tone signal (S_1) of each transmitting station (T).
, S_2...)).
2a...) are provided as many as the number of stations in the system, and output a voice signal (S) only when a tone signal with a frequency outside the voice band from the desired transmitting station (T) is detected. A transmitting station identification method characterized by monitoring and displaying which station is transmitting based on a frequency outside the audio band of a tone signal. (2) In a communication system in which a plurality of stations transmit and receive signals using the same carrier frequency, the plurality of transmitting stations (T) include a bandpass filter (2) that removes unnecessary components in the audio signal (S), A tone signal generator (3) that generates a tone signal (S_1, S_2...) of a frequency outside the audio band specified in accordance with the system of the receiving station (R), and this generator (3) an adder (4) that superimposes the output signals S_1, S_2 on the output (S) of the bandpass filter (2);
It consists of a transmitter (5) that transmits the output of
) includes a receiving section (6) that receives and demodulates the transmission output of the transmitting section (5) of each transmitting station (T), and a receiving section (6) that receives the demodulated signal output from this receiving section (6) and generates a tone signal (S_1, S_2・
. tone signals (S_1, S_2・
...) passing through a plurality of bandpass filters (9, 9a
) and these bandpass filters (9, 9a,
It consists of a detector (10, 10a...) that inputs the output of a detector (10, 10a...) and outputs a detection signal, and a detection circuit (12, 12a...) that is provided as many times as the number of stations in the system. ...)
Among these detection circuits (12, 12a...), a tone signal (S_1, S_2...) with a frequency outside the voice band from the desired transmitting station (T) is detected. Only in this case, this detection output causes the audio output control section (11
) for outputting a voice signal (S) and for displaying the tone signal (S_1, S_2, . . . ).