JPH1131994A - Transceiver - Google Patents

Abstract

(57) [Problem] To enable simultaneous bidirectional communication at the same frequency in a transceiver. SOLUTION: A transmission signal and a trigger signal TG are transmitted from a master station to a slave station using a half of the cycle T with reference to a trigger signal TG which is sequentially repeated at a constant cycle T. Is transmitted to the master station from the slave station so that the transmission can be performed using the remaining half of the period T with reference to the trigger signal TG received at the slave station. The timing is controlled.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transceiver capable of simultaneously performing two-way communication on the same frequency.

[0002]

2. Description of the Related Art Conventionally, as a transceiver capable of performing bidirectional communication, a transceiver which performs communication alternately using the same frequency is known. Also,
There is known a method in which two frequencies can be used in pairs to enable two-way simultaneous communication.

[0003]

However, in this communication method of alternately communicating using the same frequency, while one transceiver is transmitting to the other transceiver, the other transceiver side transmits the signal to the other transceiver. Because it was not possible to transmit to the transceiver side, there was an inconvenience of usability inconvenience,
In the method that enables two-way simultaneous communication by using these two frequencies as a pair, there is an inconvenience that frequency utilization efficiency is not good.

[0004] In view of the above, it is an object of the present invention to enable simultaneous two-way communication on the same frequency, and to eliminate these disadvantages.

[0005]

According to the present invention, a transmission signal and a trigger signal TG are transmitted from a master station to a slave station using a half of the cycle T with reference to a trigger signal TG which is sequentially repeated at a constant cycle T. , And a reply transmission from the slave station to the master station is performed based on the trigger signal TG received by the slave station so that the slave station can transmit using the remaining half of the period T. The transmission timing of the information and the return information is controlled so that the same frequency can be used for two-way communication at the same time, and the utilization efficiency of the information carrier frequency is improved.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the transceiver according to the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 100 denotes a transmitting unit;
0 shows a circuit block diagram of the receiving unit.

The receiving unit 200 includes a receiving antenna 1, a high-frequency amplifier 2, a receiving frequency converter 3, a receiving local oscillator 8,
It comprises an intermediate frequency amplifier 4, a demodulation detector 5, an audio amplifier 6, a speaker 7, a two-input one-output NAND gate 10, and a reception-side timer 11.

One of the two inputs of the receiving NAND gate 10 is connected to the demodulation output of the demodulation detector 5 through a signal level smoothing time constant circuit (not shown). The other input is connected to the output of a transmission timer 24, which will be described later, and is connected to the reception NAND.
The output side of the gate 10 is connected to the input side of the reception side timer 11, and the output side of the reception side timer 11 is configured to be connected to another input side of the transmission side NAND gate 23 described later.

The transmitting unit 100 includes an arithmetic unit 12, a trigger detector 13, a synchronization signal generator 14, and a local oscillator 1 on the transmitting side.
5, crystal resonator 16, modulator 17, high-frequency power amplifier 1
8, a transmitting antenna 19, a transmitting microphone (referred to as a microphone in the following description) 20, an audio amplifier 21, an audio detector 22, a transmitting NAND gate 23,
It comprises a transmission timer 24, a power switch 25, a trigger signal generator 26, a clock signal generator 27, a clock signal generation crystal resonator 28, and a communication switch 29. The transmission-side NAND gate 23 is constituted by a two-input one-output NAND gate.

The crystal resonator 16 is connected to the local oscillator 15 on the transmitting side, and the output side of the local oscillator 15 on the transmitting side is connected to the modulator 17.
5G is connected to the output side of the arithmetic unit 12, the output side of the modulator 17 is connected to the input side of the high-frequency power amplifier 18, and the output side of the high-frequency power amplifier 18 is connected to the transmission antenna 19.

The output side of the microphone 20 is connected to the input side of an audio amplifier 21 and an audio detector 22, and the output side of the audio amplifier 21 is connected to a modulation signal input 17M of a modulator 17.
And the output side of the audio detector 22 is connected to a power switch 25.
And the other input of the transmission NAND gate 23 is connected to the output of the reception timer 11. The communication switch 29 is constituted by a manual on / off switch, and is connected between a power input side of the power switch 25 and a DC power supply (not shown).

The power output side of the power switch 25 is connected to the local oscillator 15 on the transmitting side, the modulator 17 and the high-frequency power amplifier 1.
8 are connected to respective power supply lines (not shown).

Next, in the connection configuration described above, the on / off control of the local oscillator 15 on the transmission side by the outputs of the NAND gate 10 on the reception side and the NAND gate 23 on the transmission side includes 1) a transmission / reception standby state, 2) a transmission only state, 3) A description will be given of each of the states of only the reception) and the bidirectional transmission / reception state.

The reason why the reception timer 11 and the transmission timer 24 are provided is that the output of the reception NAND gate 10 and the output of the transmission NAND gate 23 change from high level to low level instantaneously due to disturbance or the like. Signal level holding means inserted for the purpose of preventing a malfunction when the voltage drops, keeps a high level for about 5 seconds even in the case of an instantaneous drop, and without delay when each output rises from a low level to a high level. Since it has a function of starting up, it is a function that is not directly necessary for the description of these four states, and is omitted in the following description of each state.

1) Transmission / reception standby state In the transmission / reception standby state, the receiving-side NAND gate 10
Both the input side of (1) and the input side of (1) of the transmission-side NAND gate 23 become low level (hereinafter, referred to as L), so that the other input side of the reception-side NAND gate 10 and the transmission side All other inputs of the NAND gate 23 are at a high level (referred to as H in the following description).
Since the output side of the reception-side NAND gate 10 and the output side of the transmission-side NAND gate are each held at H, these two NAND gates 10 and 23 are balanced. Therefore, this level H is supplied to the on / off control input 15G of the transmitting side local oscillator 15, and the transmitting side local oscillator 15 is in a power supply standby state.

2) Only transmission state The communication switch 29 is turned on manually, and the operation unit 12
Is turned off, when the voice is input to the microphone 20, the output side of the voice detector 22 becomes H during the input of this voice and for several seconds following this, the input side of 1 of the transmission side NAND gate 23 becomes H, and the transmission side NAND gate 23, the output side of the receiving side NAND gate 10 becomes H, the output side of the receiving side NAND gate 10 becomes H, the two NAND gates 10 and 23 are balanced, and the power supply switch 25 is turned on, and the transmitting side local oscillator 15, modulator 17 and Power is supplied to a power supply line (not shown) of the high-frequency power amplifier 18.

Therefore, the transmitting side local oscillator 15 oscillates the frequency F 1 by the crystal resonator 16, and the frequency F 1 is supplied to the modulator 17, which modulates the frequency F 1 with the audio signal from the audio amplifier 21. A modulated high-frequency amplitude modulation signal is generated, the high-frequency amplitude modulation signal is power-amplified by the high-frequency power amplifier 18, supplied to the transmission antenna 19, and is transmitted from the transmission antenna 19.

3) Reception Only State In the reception state, one input of the receiving NAND gate 10 is H, one input of the transmitting NAND gate 23 is L, the output of the receiving NAND gate 10 is L, and The output side of the NAND gate 23 is H, the NAND of the receiving side
The other input side of the gate 10 is H, the transmission side NAND gate 2
3 becomes L and both of these NANs become L.
The D gates 10 and 23 are balanced, the local oscillator 15 on the transmitting side is turned off, the transmitting state ends, and the receiving state is entered.

In this receiving state, the receiving antenna 1
Is supplied to the high-frequency amplifier 2 where it is amplified to a predetermined high-frequency signal level, and the amplified signal is supplied to the reception frequency converter 3, while the transmission signal is transmitted to the reception frequency converter 3. The signal of the fixed frequency F1 is supplied from the local oscillator 8 for reception, which is controlled by the crystal resonator 16 shared with the unit 100 and generates the signal of the fixed frequency F1, and the frequency of the signal from the high-frequency amplifier 2 is changed to the intermediate frequency. The frequency-converted signal is supplied to the intermediate frequency amplifier 4 and further amplified to a predetermined signal level.

The signal amplified by the intermediate frequency amplifier 4 is supplied to a demodulation detector 5 where it is detected and demodulated into an audio signal. The audio signal is supplied to an amplifier 6 for amplification, and then supplied to a speaker 7 for audio. And make it regenerate. 4) Two-way transmission / reception state In the two-way transmission / reception state, when the arithmetic unit 12 starts the transmission from the microphone 20 by turning on the communication switch 29 manually and starting the transmission from the microphone 20, the input side of the receiving NAND gate 10 and the transmitting side NAND The input side of 1 of the gate 23 becomes H,
The other input side of the receiving side NAND gate 10 is L, the receiving side N
The output side of the AND gate 10 is H, the other input side of the transmission side NAND gate 23 is H, and the transmission side NAND gate 2
3 outputs L and both NAND gates 1
0 and 23 are balanced, the local oscillator 15 on the transmitting side is turned on, and a simultaneous bidirectional transmitting and receiving state using the crystal resonator 16 having the same frequency is used on the transmitting side and the receiving side.

Further, at the time of transmission from the transmitting side (hereinafter, referred to as a master unit) to the receiving side (hereinafter, referred to as a slave unit) in the bidirectional transmission / reception state, as shown in FIG. A trigger signal TG having a T is sequentially generated, and as shown in FIG. 2B, only the first half section ta of the repetition period T of the trigger signal TG is sequentially used for each repetition period T. The information to be transmitted and the trigger signal TG are transmitted.

In order to realize the transmission state as shown in FIG. 2B, in the example shown in FIG. 1, the clock signal generator 27 has a repetition period of the period T based on the crystal resonator 28 for generating a clock signal. A first clock signal is generated, and the generated clock signal is supplied to a synchronizing signal generator. In the synchronizing signal generator, a trigger signal TG having a repetition cycle of the cycle T is generated based on the clock signal. .

The trigger signal TG is supplied to the arithmetic unit 12
The trigger signal T is supplied to the
With reference to G, the modulator 17 is operated for each period ta of the first half of the repetition period T of the trigger signal TG for each trigger signal TG, and the modulator 17 is stopped for each period tb of the second half of this period T. In the state in which the modulator 17 is controlled, the signal of the frequency F1 is converted from the trigger signal TG and the audio signal from the audio amplifier 21 to the modulator 1.
7B, the signal Sm having the modulation waveform shown in FIG. 2B is generated by the modulator 17, and the generated signal is amplified by the high-frequency power amplifier 18 to transmit the signal Sm.
To the slave unit.

In this bidirectional transmission / reception state,
Upon receiving the transmission from the master unit, the slave unit enables the received contents to be listened to by the speaker 7, and supplies a signal demodulated by the demodulation detector 5 to the trigger signal detector 13. The detector 13 extracts the trigger signal TG transmitted from the master unit. Then, the extracted trigger signal TG is output to the synchronization signal generator 1.
4 and the synchronization signal generator 14 delays the extracted trigger signal TG by ta.
A new trigger signal TGN having a repetition period T as shown in FIG. 2C is generated.

The trigger signal TGN is applied to the arithmetic unit 1
The modulator 17 is operated by the calculator 12 for each period ta of the first half of the repetition period T of the trigger signal TGN with reference to the trigger signal TGN. In a state where the modulator 17 is controlled so as to stop the modulator 17 at a time, the trigger signal TG and the audio signal from the audio amplifier 21 are processed in the same manner as in the case of the master unit, and shown in FIG. 2D. The modulator 17 generates the signal Sn having the modulated waveform, and transmits the generated signal to the master unit.

As described above, the master unit and the slave unit can receive the transmission from the other party when they are not in the transmission state at a period interval of half of this period T. Communication in the two-way simultaneous transmission / reception state can be realized without any trouble between the master unit and the slave unit.

Next, an example of a communication operation performed by a transceiver user using a transceiver having the above-described configuration and operating will be described.

Both transceivers for communication are placed in the transmission / reception standby state described above. In the following description, the transceiver that starts transmission first will be referred to as a parent device, and the transceiver that will receive transmission from the parent device first will be referred to as a child device.

When the master unit turns on the communication switch 29 manually and starts a conversation with the microphone 20, the master unit starts the transmission unit 100.
The whole is also in the operating state, the trigger signal TG and the high-frequency signal modulated by the audio signal are transmitted to the slave unit, and the trigger signal is detected and demodulated by the trigger detector 13 on the slave unit, and the demodulation trigger signal causes an incoming call. Trigger an alarm (not shown). When the operator is present at the slave unit, the communication switch 29 is manually turned on to put the transmitting unit 100 on the slave unit into an operation waiting state.

If a voice response is made from the microphone 20 of the slave unit while listening to the contents transmitted from the master unit, the two-way transmission / reception state is established. , Can receive transmission from the other party when it is not in the transmission state.

When an audio signal is transmitted and received in a time-division manner as in the above-described embodiment, since the audio signal is intermittent at the cycle of the trigger signal TG or TGN, it is theoretically possible to cause distortion in the audio signal. Inevitably, by selecting the repetition period T of the trigger signal TG or TGN at a frequency sufficiently high with respect to the frequency band of the audio signal, the influence of this distortion can be reduced to a level that does not cause a hearing problem. It is possible to further reduce the influence of this distortion to a level that does not cause a problem by inserting a low-pass filter having a pass band in the frequency band of the audio signal between the demodulation detector 5 and the audio amplifier 6. it can.

In the above embodiment, the trigger signal T
Regarding the method of removing G or TGN from the audio signal,
Since these trigger signals are pulse signals that repeat at a constant period T, they can be easily removed using a well-known pulse signal removal circuit.

In the above-described embodiment, when the trigger signal TGN is generated based on the transmitted trigger signal TG, even if a part of the trigger signal TG has a signal loss, the trigger signal TG itself has a constant period T pulse. Since the signal is generated as a signal, it can be easily complemented by using a known automatic frequency control (AFC) circuit by utilizing this periodicity.

According to the above-described embodiment, two-way communication can be simultaneously performed using the same frequency, the efficiency of frequency utilization can be improved, and the conventional two-way communication can be performed simultaneously. Circuit switching for switching to the one-way communication state can be realized only by disconnecting the output of the trigger signal generator 26 from the modulator 17 and is extremely easy.

[0036]

According to the present invention, two-way communication can be performed simultaneously using the same frequency, and the frequency utilization efficiency is improved.

[Brief description of the drawings]

FIG. 1 is a circuit block diagram showing one embodiment of a circuit configuration of a transceiver of the present invention.

FIG. 2 is a diagram for explaining the operation of the circuit block diagram of FIG. 1;

[Explanation of symbols]

100 transmitter, 200 receiver, 12 checker, 13
Trigger detector, 14 synchronization signal generator, 23 transmitting side N
AND gate, power switch, 26 trigger signal generator, 27 clock signal generator, 10 receiving NAN
D gate, 13 Trigger signal detector, 14 Synchronous signal generator, 16 Crystal resonator

Claims (1)

[Claims] 1. A transmission signal and a trigger signal are transmitted from a master station to a slave station using a half of this cycle period as a reference, based on a trigger signal which is sequentially repeated at a fixed cycle. The transmission to the master station controls the timing of transmission of the transmission information and the reply information based on the trigger signal received by the slave station so that the transmission can be performed using the other half of the period. A transceiver characterized by the following.