JPH07231275A - One-wave simultaneously transmission reception radio equipment - Google Patents

Abstract

PURPOSE:To improve the convenience of use by inserting an identification signal of a sender station to a start and an end of transmission so as to use the equipment in the same sense as that of a conventional telephone set without notifying any restriction. CONSTITUTION:A control section 5 starts a high frequency transmission section 8 on the opportunity of a transmission start timing signal of a voice compression intermittent signal V1 fed from a time axis companding section 2 in the speech start mode. A bit synchronizing signal B, a frame synchronizing signal F and an identification code signal ID are read from an identification code storage device 4 for the first transmission period and outputted to an MSK MODEM section 6 sequentially. Then they are frequency-modulated and sent from an antenna 10. The control section 5 starts its processing on the opportunity of a transmission start timing signal of the voice compression intermittent signal V1 fed from a time axis companding section 2 in the speech stop mode. An identification signal comprising a bit synchronizing signal B, a frame synchronizing signal F and an identification code signal ID is read from the identification code storage device 4 for the final transmission period and outputted to the MSK MODEM section 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication system which uses a single radio transmission channel to obtain a call state as if two-way simultaneous call is obtained, that is, so-called single wave simultaneous transmission / reception. System radio. Here, one wave has the same meaning as one frequency.

[0002]

2. Description of the Related Art As the effective use of wireless channels has been strongly screamed, a communication system called a single wave simultaneous transmission / reception system has been attracting attention in recent years.
This one-wave simultaneous transmission / reception method is also called a time division simultaneous transmission / reception method.It creates a vacant time required for alternate time division transmission by time compression and time expansion of a voice signal, which enables both simultaneous transmission and reception. In order to describe it more concretely, it is made to create a call-in-progress state. First, as shown in FIG. 4 (a), signals such as a microphone input signal which are continuous in time are sequentially input for a period T. Each time, the time axis compression circuit performs time compression to a period Tx = Rx≈T / 2, and then the same figure (b)
Create a voice compression intermittent signal as shown in. As the period T at this time, a period of, for example, about 400 milliseconds is selected. Therefore, in this case, the period Tx = Rx≈200 milliseconds.

Correspondingly, the transmission / reception operation of one of the wireless devices, for example, the calling wireless device, is divided into a transmission period Tx and a reception period Rx alternately as shown in FIG. At the same time, the transmission / reception operation of the other radio, that is, the radio of the called side is divided into a reception period Rx and a transmission period Tx alternately as shown in FIG. By transmitting the intermittent signal from one side to the other side, and by making the T / 2 period created within the period T the reception period of the signal from the other party, bidirectional transmission is possible under the carrier signal of a single frequency. It enables simultaneous transmission and reception.

Then, as shown in FIG. 4 (e), the audio compression intermittent signal received in the reception period Rx is extended to approximately twice the time and returned to a continuous signal as shown in FIG. 4 (f). , To obtain the received voice signal. Switching of transmission and reception at this time,
As shown in FIG. 4 (b), the timing of time compression / time expansion is managed by the time division synchronizing signal added to the audio compression intermittent signal.

As a conventional technique of this type of single-wave simultaneous transmission / reception system, the description in International Publication No. WO91 / 02414 can be mentioned.

[0006]

However, the above-mentioned prior art has not taken into consideration the operation under the radio wave control by the government, and has a problem of deterioration in usability. That is, for example, in the Radio Law of Japan, when operating a communication system using such a radio, at least at the start and end of a call, it is possible to identify each radio,
For example, transmission of predetermined information such as a call sign is obligatory.

Therefore, in the prior art, it is necessary for the caller to call a predetermined call sign such as the number of each radio as necessary. Therefore, for a person who is accustomed to a call using an ordinary telephone or the like, Is accompanied by a great deal of incongruity and a sense of duty, which is inconvenient to use, and in some cases causes a problem in operation.

The object of the present invention is, even in compliance with laws and regulations,
It is an object of the present invention to provide a one-wave simultaneous transmission / reception wireless device which does not require a call sign or the like to be called by the caller and can be provided with the same excellent usability as an ordinary telephone.

[0009]

The above object is to provide a control means for inserting the identification signal of the local station in the transmission signal in the one-wave simultaneous transmission / reception wireless device, and to provide a signal to be transmitted first at least at the start of a call. This is achieved by inserting the identification signal of the own station into the last signal transmitted at the end of the call.

[0010]

The control means for inserting the identification signal of the own station into the transmission signal works so that the identification signal of the own station is automatically transmitted at the start time and the end time of the emission of the radio wave.

Therefore, the caller can make a call in the same manner as an ordinary telephone without being aware of any restrictions, and there is no fear that the usability will deteriorate.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A one-wave simultaneous transmission / reception wireless device according to the present invention will be described in detail below with reference to the illustrated embodiments.

FIG. 1 shows an embodiment of the present invention. In this figure, first, the time axis companding unit 2 outputs a voice signal input from a voice signal input terminal 1 as shown in FIG. (Microphone input signal) v is sequentially divided for each period T, time-compressed to 1 / 2.25 (compression ratio) in the transmission period Tx, and an audio compression intermittent signal as shown in FIG. In addition to the function of creating V ₁ , as shown in FIG. 4 (e), during the reception period Rx, the audio compression intermittent signal input from the FM demodulation unit 12 (described later) is approximately doubled (2.25 times). ) Is extended to return to a continuous signal, and a received voice signal as shown in FIG.

The time axis companding section 2 also functions to generate the time division synchronizing signal S and the transmission switching signal SW, whereby the high frequency transmitting section 8 is first transmitted in the transmission period Tx. To move the antenna switch 9 to the transmitting side to stop the high frequency receiver 11 and
During the reception period Rx, the high frequency transmitter 8 is stopped,
The antenna switch 9 is turned down to the receiving side, and the high frequency receiving unit 11
So that control to operate can be obtained.

The control unit 5 is constructed so as to take four kinds of operation modes by operating the call switch 14. That is, even when the call switch 14 is pressed in the call stopped state, the call mode is not immediately entered, but the call start processing mode is first entered and then the normal call mode is entered. . Also, when the call switch 14 is pressed while in the call mode,
Therefore, the call is not immediately ended, but the call end processing mode is first entered and then the call is stopped.

Therefore, first, the operation when the control section 5 is in the call mode will be described. In this call mode, the operation described in FIG. 4, that is, the one-wave simultaneous transmission / reception operation is executed. Therefore, in the transmission period Tx,
The audio compression intermittent signal V ₁ is output from the time axis companding unit 2 to the MSK modulating unit 6 and the FM modulating unit 7, is FM-modulated and is output to the high frequency transmitting unit 8, is amplified, and then is transmitted via the antenna switch 9. In the reception period Rx, the signal received by the antenna 10 is then input from the high frequency reception unit 11 to the FM demodulation unit 12, and the demodulated received voice compression intermittent signal V ₁ is time-axis expanded. The received audio signal that has been supplied to the unit 2 and thus has been extended in time and returned to the continuous state is supplied to the received audio signal output terminal 16 via the received audio mute circuit 15. Therefore, the operation in this call mode is the same as the simultaneous transmission / reception operation in the conventional one-wave simultaneous transmission / reception wireless device.

Next, the operation when the control unit 5 enters the call start processing mode will be described. As described above, the call start processing mode is a mode in which the call is taken only for the first transmission period Tx after the call switch 14 is pressed in the call stopped state, and thereafter, the normal call mode is automatically entered. This is one of the features of the present invention together with a call termination processing mode described later.

In this call start processing mode, the control unit 5 sends a timing signal for starting transmission of the intermittent audio compression signal V ₁ supplied from the time axis companding unit 2, that is, a timing signal indicating the end of transmission of the time division synchronizing signal. In the first transmission period Tx after the high frequency transmitter 8 is activated,
Instead of part or all of the audio compression intermittent signal, a bit synchronization signal (a signal for bit synchronization of the identification signal) B, a frame synchronization signal (a signal for frame synchronization of the identification signal) F, and an identification code signal (self A code which is a main body for identifying a station) ID is read from the identification code storage device 4, and these are sequentially read by M
Output to the SK modulator / demodulator 6. Therefore, the identification signal in this embodiment is composed of the bit synchronization signal B, the frame synchronization signal F, and the identification code signal ID, but hereinafter, the entire identification signal is also represented by ID.

The identification signal input to the MSK modulator / demodulator 6 is modulated into an MSK signal, and the FM modulator 7 then FM-modulates it.
After being modulated, it is amplified by the high frequency transmitter 8 and transmitted from the antenna 10. The MSK modulator / demodulator 6 is provided in this embodiment because the identification signal is a digital signal.

When the transmission of the identification signal is completed, the control unit 5 automatically switches to the call mode and controls the operation of the MSK modulation / demodulation unit 6 by switching the voice compression intermittent signal V ₁ from the time axis companding unit 2 to F
The operation is switched to the output to the M modulator 7, the operation is switched to the operation in the call mode, and the one-wave simultaneous call operation is started.

Next, the operation when the control unit 5 enters the call stop processing mode will be described. This call stop processing mode is used when the call switch 14 is in the call mode.
It is a mode that takes only the last transmission period Tx after the button is pressed, and then automatically shifts to a call stop. It will be one.

The operation in this call stop processing mode is almost the same as the above-mentioned call start processing mode. When there is an input from the call switch 14, the control unit 5 enters the call stop processing mode and the time axis compression is expanded. Processing is started from the section 2 by a transmission start timing signal of the audio compression intermittent signal V ₁ , that is, a timing signal indicating the end of transmission of the time division synchronization signal, and bit synchronization is performed in the final transmission period Tx by the high frequency transmission section 8. An identification signal composed of the signal B, the frame synchronization signal F, and the identification code signal ID is read from the identification code storage device 4, and instead of a part or all of the audio compression intermittent signal in this period, the MSK modulator / demodulator 6 is sequentially provided. Output to.

The identification signal input to the MSK modulator / demodulator 6 is modulated into an MSK signal, and the FM modulator 7 then FM-modulates it.
After being modulated, it is amplified by the high frequency transmitter 8 and transmitted from the antenna 10. And the control unit 5
When the transmission of the identification signal is completed, the time axis companding unit 2 and the M
The SK modulator / demodulator 6 is stopped and the call is stopped.

Therefore, according to this embodiment, the identification signal is automatically transmitted from both the calling side and the called side at the beginning and end of the emission of the radio wave, so that the caller can make a call. At this time, it is possible to identify and monitor the wireless device without giving a special call sign, and always provide good usability.

Next, the operation of the remaining part of the embodiment shown in FIG. 1 will be described. In this embodiment, as described above, the identification signal is transmitted at the start point and the end point of the call, but if it is reproduced as a voice signal, it will be annoying. However, according to this embodiment, as described below, the generation of noise due to this identification signal is automatically suppressed.

That is, in this embodiment, in order to prevent the other party's radio from being affected by the transmission of the identification signal, the time axis companding unit 2 delays the voice signal and the identification signal. Is. That is, the transmission start timing of the identification signal to be transmitted at the end time of the emission of the radio wave is transmitted to the partner radio having a means for disconnecting the voice for a certain period of time by the bit synchronization signal and the frame synchronization signal. From the time of transmission of the bit synchronization signal and the frame synchronization signal which form part of the identification signal.
The time is divided by 25 (a value obtained by subtracting 1 from the elongation ratio, which is 1 or more) after the lapse of time. Here, the expansion ratio is a value obtained by dividing the time length of the output signal after expansion when the time axis is expanded by the time axis companding unit 2 by the time length of the input signal before expansion. .

First, as described above, the reception period R of the own station
At x, the signal transmitted from the radio of the communication partner is
Antenna 10, antenna switch 9 and high frequency receiver 1
1, is demodulated by the FM demodulation unit 12, and then supplied to the time axis companding unit 2. At this time, the squelch circuit 1 is further supplied.
3 and MSK modulator / demodulator 6.

First, the squelch circuit 13 detects a noise component of the demodulated signal, and when the noise component exceeds a threshold value, generates a squelch signal SQ for cutting the voice signal to expand the time axis. Output to section 2. Therefore, the time axis companding unit 2 time-expands the squelch signal SQ together with the demodulated audio signal, and the time-expanded squelch signal SQ.
The received voice mute circuit 15 is controlled by Q.

As a result, the time-extended audio signal is switched by the reception audio mute circuit 15, and when the noise component exceeds the threshold value, the path of the reception output terminal 16 is disconnected from the time-expanded audio signal. However, muting operation can be obtained.

On the other hand, the MSK modulator / demodulator 6 demodulates the MSK signal and outputs it to the controller 5. Therefore, the control unit 5
Detects the frame synchronization signal of the identification signal, controls the reception audio mute circuit 15 from the time when this signal is detected until the end of the time-extended identification code signal, and The path to the reception output terminal 16 is cut off.

Here, looking at the time when the emission of the radio wave is started and when the identification signal transmitted first is received, since the radio wave is not sensed before the identification signal is received, the squelch is not sensed. The level of the noise component input to the circuit 13 is considerably high.

Therefore, in this embodiment, the squelch circuit 1
The squelch signal SQ output from the input terminal 3 is input to the time axis companding unit 2 so that the time from when the identification signal is received until the noise component input to the squelch circuit 13 decreases to a certain value or less is 2 Time until the connection path of the audio signal, which has been expanded by .25 times and has been disconnected by the reception audio mute circuit 15, is closed (squelch response time, usually 30 to 100 m
s) is set to be longer than the duration of the bit sync signal and the frame sync signal (about 23 ms at 2400 BPS). Therefore, according to this embodiment, when the radio wave emission is started, The identification signal is not output as a voice signal.

Next, the operation of suppressing the identification signal when the emission of radio waves in this embodiment is terminated will be described. As is apparent from FIG. 1, in this embodiment, the delay circuit 3 is provided in the path of the timing signal indicating the start of transmission of the audio compression intermittent signal, that is, the timing signal indicating the end of transmission of the time division synchronizing signal. The timing signal indicating the end of transmission of the time division synchronizing signal is delayed by 50 ms before being supplied to the control unit 5.

FIG. 3 shows the relationship between the expansion operation of the bit sync signal and the frame sync signal and the delay time. Here, S is a time division synchronizing signal, V ₁ is an audio compression intermittent signal before decompression, and V ₁ '
Is a voice compression intermittent signal after decompression, B is a bit synchronization signal before decompression, B ′ is a bit synchronization signal after decompression, F is a frame synchronization signal before decompression, F ′ is a frame synchronization signal after decompression, and I
D is an identification signal before expansion and ID 'is an identification signal after expansion.

Now, in the receiving radio, the time axis companding unit 2
When the time axis is extended by, the delay time until the input signal is output is zero immediately after the time division synchronizing signal S is received, and then linearly increases with time, and the time division synchronization is performed. This is 1.25 times the time elapsed since the signal S was received.

For example, if the elongation ratio is 2.25 times, 200 m
If the input signal having a time length of s is expanded to 450 ms, 200 ms from the timing of generation of the time division synchronizing signal S
The signal input when the time has passed is 1.25 times 250 m
The output is delayed by s. The output timing is 450 ms from the time when the time division synchronizing signal S is generated.
It is the time when it has passed.

Since the delay circuit 3 is provided, when the time-division synchronization signal S is generated 50 ms after the generation of the time-division synchronization signal S, the bit synchronization signal B starts to be received, and when the time-division synchronization signal S is elapsed 112.5 ms. It is assumed that the reception of the frame synchronization signal F of the same identification signal is finished and the voice signal (identification signal) is cut off when the reception end is detected (bit synchronization signal B + frame synchronization signal F ≦ 62.5 ms).

Then, the timing at which the time axis companding unit 2 starts to output the bit synchronizing signal B whose time axis has been extended is when the signal starts to be received when 50 ms has elapsed from the time division synchronizing signal S. And then 50ms
When the time elapses, that is, 62.
52.5 (50 ms x 1.25) delayed 112.5 ms (5
It is the time when 0 ms × 2.25) has elapsed.

Therefore, when the frame sync signal F is detected and the expanded audio signal is cut off, the expanded identification signal is the end point of reception of the bit sync signal and the frame sync signal.
Since the delay more than (when the audio signal is disconnected) is given, the identification signal is supplied after the disconnection, and there is no fear that this will be generated from the speaker.

Here, the expansion ratio is n, and as shown in FIG. 3, the length of the bit synchronization signal B and the frame synchronization signal F (B
+ F) is K, the reception start time of the bit synchronization signal B is x, the output start time of the expanded signal B ′ is X ₁ , the frame synchronization signal F
Let X ₂ be the end point of reception of X ₁ = nx, X ₂ = x +
It becomes K.

Then, in this case, in order to prevent the expanded identification signal (B + F + ID) from being output, it is sufficient that X ₁ > X ₂ → nx> x + K → x> K / (n-1). .

Therefore, in order to prevent the time-extended identification signal from being output, the identification signal transmitted when the emission of the radio wave is terminated is transmitted from the end of the transmission of the time-division synchronization signal. It suffices to start from a point delayed by a time equal to or more than the time obtained by dividing the time of the bit sync signal and the frame sync signal by the value obtained by subtracting 1 from the expansion ratio of the compressed signal of the time division simultaneous transmission / reception radio set. In the above description of the embodiment, numerically X ₁ = X ₂ .

Therefore, according to this embodiment, it is possible to reliably suppress the risk of extra noise due to the insertion of the identification signal. In particular, when the voice signal level of the call is lower than the identification signal, if the identification signal is output, the sound due to the identification signal may have a shock on the ear. It is possible to surely eliminate such a fear.

Further, according to this embodiment, the identification signal is
In the first audio compression intermittent signal cycle after the timing signal indicating the end of transmission, it is configured to be sent instead of the audio compression intermittent signal, so that the identification signal is subjected to time axis compression / expansion processing during modulation / demodulation. Therefore, according to this embodiment, it is possible to prevent problems such as phase distortion occurring in the identification signal due to phase distortion generated by compression and expansion.

Next, FIG. 2 shows another embodiment of the present invention.
This embodiment is different from the embodiment of FIG. 1 in that the delay circuit 3 provided in the path of the timing signal indicating the start of transmission of the audio compression intermittent signal in the embodiment of FIG. Since the same function is provided inside the section 2, the operation and effect thereof are the same as those of the embodiment of FIG. 1, and detailed description thereof will be omitted.

[0046]

According to the present invention, in the one-wave simultaneous transmission / reception type radio by time division time compression / expansion, the identification signal of the transmitting station is inserted at the beginning and the end of the transmission. The radio can be operated with the same feeling as an ordinary telephone without paying attention to regulations, and the usability can be sufficiently improved under the observance of laws and regulations.

Further, according to the present invention, the fact that the radio device on the receiving side receives the frame synchronization and disconnects the reception output signal for a certain period of time is used to transmit the radio wave when the emission of the radio wave is terminated. The identification signal can be made inaudible at the receiving side only by controlling the transmission timing of the identification signal to be transmitted, which may result when the voice signal level of the call is lower than the identification signal. It is possible to surely eliminate the risk of a shock to the ear due to the signal.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a one-wave simultaneous transmission / reception wireless device according to the present invention.

FIG. 2 is a block diagram showing another embodiment of the one-wave simultaneous transmission / reception wireless device according to the present invention.

FIG. 3 is a timing chart showing the relationship between the expansion operation of the identification signal, the bit synchronization signal and the frame synchronization signal and the delay time in the embodiment of the present invention.

FIG. 4 is a timing chart for explaining the operation of the one-wave simultaneous transmission / reception communication system to which the present invention is applied.

[Explanation of symbols]

 1 voice input terminal 2 time axis companding unit 3 delay circuit 4 identification code storage device 5 control unit 6 MSK modulation / demodulation unit 7 FM modulation unit 8 high frequency transmission unit 9 antenna switch 10 antenna 11 high frequency reception unit 12 FM demodulation unit 13 squelch circuit 14 Call switch 15 Received audio mute circuit 16 Received output terminal 17 Time axis companding unit

Claims (4)

[Claims] 1. A continuous input signal is sequentially divided at a predetermined fixed period, time compression is performed for each sectioned section to shorten the time required for transmission, and at each fixed period, before and after that period. In a one-wave simultaneous transmission / reception wireless device that enables simultaneous transmission / reception by using carrier waves of the same frequency by alternately transmitting and receiving, a control means is provided to insert the identification signal of the own station into the transmission signal, and at least the call start A single-wave simultaneous transmission / reception radio device, characterized in that an identification signal of its own station is inserted into a signal transmitted first at a time point and a signal transmitted last at a time point when a call ends. 2. A continuous input signal is sequentially divided for each predetermined fixed period, time compression is performed for each sectioned section to shorten the time required for transmission, and the fixed input is performed before and after the fixed period. In a one-wave simultaneous transmission / reception wireless device that enables simultaneous transmission / reception with a carrier wave of the same frequency by alternately transmitting and receiving, a control means is provided to insert the identification signal of the own station into the transmission signal, and when the call ends The single-wave simultaneous transmission characterized in that the identification signal of the local station is inserted into the signal transmitted last in the above with a predetermined time delay from the time division synchronization signal added to the beginning of the transmission signal. Incoming radio. 3. The invention according to claim 2, wherein the wireless device has means for cutting off the voice for a certain period of time by the bit synchronization signal and the frame synchronization signal, and the identification signal is a bit synchronization signal, a frame synchronization signal and identifications following these. From a time point delayed by a time equal to or greater than a time obtained by dividing the time of the bit synchronization signal and the frame synchronization signal, which are composed of the code signal and are components of the identification signal, by the value obtained by subtracting 1 from the expansion ratio of the time-compressed transmission signal , A one-wave simultaneous transmission / reception radio device configured to start insertion into the transmission signal. 4. The invention according to claim 1 or 2,
A one-wave simultaneous transmission / reception radio device, wherein the identification signal is configured to be inserted by replacing at least a part of a voice compression intermittent signal included in the transmission signal.