JPS6232647B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a transmitting/receiving device used as a wireless intercom.

A block diagram of a conventional example is shown in FIG. Each transceiver 1 is used as a wireless intercom, of which transceiver 1A is the main device,
Furthermore, one transmitter/receiver 1B is installed as a slave device installed indoors, and another transmitter/receiver 1C is installed at the entrance as a slave device for interacting with guests. Each transceiver 1
A, 1B, and 1C have substantially similar circuit configurations, and each includes a transmitting circuit 2 and a receiving circuit 3. The transmitting circuit 2 is made up of a calling block 6, a sending block 7, and a microphone 8. The calling block 6 is made up of a calling button and a calling signal generation circuit, and when calling a desired party, the sending block 7 sends a calling signal. It is superimposed on the generated carrier wave. Voice is input through a microphone 8, modulates a carrier wave, and transmits it through a transmitting antenna 9.
Here, the transmission frequency of the transmitter/receiver 1A as the parent device is a, and the transmitter/receiver 1B, 1 of the other two slave devices is
The transmission frequency of C is b, and each transceiver 1
The transmitting and receiving frequencies of A, 1B, and 1C are made different so that transmission and reception can be performed simultaneously. The receiving circuit 3 is composed of a receiving block 11 and a speaker 12. Reception block 1
1 is amplified, frequency-converted, and demodulated from a receiving antenna 10, and this demodulated signal is outputted as audio from a speaker 12. Here, as mentioned above, the reception frequency of the master transceiver 1A is b, and the other two slave transceivers 1B,
The reception frequency of 1C is a. Further, the master transceiver 1A is provided with a call detection circuit 4 that detects a call signal included in the carrier waves transmitted from the slave transceivers 1B and 1C to identify the other party.

Currently, a communication between the master transmitter/receiver 1A and the indoor slave transmitter/receiver 1B is in progress at frequencies a and b. There is a visitor here, and the transmitter/receiver 1 of the entrance slave unit
C presses the call button to call the transceiver 1A. As a result, power is applied to the transmitting circuit 2 and the receiving circuit 3 of the transceiver 1C, and as shown in FIG.
The output containing the signal is transmitted to the transmitter/receiver 1A, and the receiving circuit 3 enters the receiving state as shown in FIG. 2d. In the master transmitter/receiver 1A, the call detection circuit 4 detects that there is a call from the slave transmitter/receiver 1C (signal CS' in FIG. 2a).
Therefore, since the call is given priority to the visitor, the transmitter/receiver 1B that is currently on the call is informed of the fact that the visitor is a visitor, and the call with the receiver/transmitter 1B is terminated at time _t2 . Therefore, after time _t2 , the master transmitter/receiver 1A and the slave transmitter/receiver 1C are ready for communication. However, since the receiving circuit 3 of the transmitter/receiver 1C is turned on from the time t ₁ when the transmitter/receiver 1C calls the master transmitter/receiver 1A, the time t when the call with the transmitter/receiver 1B is disconnected starts from that time t ₁ . Up to ₂ , there was a problem in which the content of calls between the transceivers 1A and 1B was leaked to the transceiver 1C, which was a slave device for the entrance.

The present invention has been provided in view of the above-mentioned points.The first object of the present invention is to prevent the content of the call from being leaked to the calling party when one party is calling the other party.
The purpose of the present invention is to provide a transmitting/receiving device having the following objectives, and a second objective of smoothly switching a call between a called party and a calling party.

Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 3 shows a block diagram of this embodiment. In this embodiment, the transmitter/receiver 1A as the main device is equipped with a switch SW which is a retransmission means for once turning off the transmission of the transmitting circuit 2 and transmitting the carrier wave again. The transmitter/receiver 1B is the same as the conventional one, and the transmitter/receiver 1C is the slave device for the entrance.
A mute control circuit 5, which will be described later, is added. The receiving block 11 of the receiving circuit 3 of the transmitter/receiver 1C amplifies the signal from the receiving antenna 10, converts the frequency, and demodulates the signal as in the conventional case, and also detects the carrier wave of the receiving frequency, for example, a high frequency amplification block in the first stage. It has a carrier wave detection means of a width circuit,
It is equipped with a squelch circuit that operates depending on the presence or absence of the output of the carrier wave detection means, and a mute circuit that can turn on and off the audio output of the audio circuit that is controlled by an external input. The mute control circuit 5 is composed of an RS flip-flop circuit 13, an AND circuit 14, an OR circuit 15, etc., and sends a synchronization signal between the squelch output of the receiving block 11 and the calling signal of the calling block 6 to the mute circuit of the receiving block 6. input, the mute circuit is turned on and off, the audio circuit is turned on and off, and the sound from the speaker 12 is cut off or output. Here, the squelch output of the squelch circuit outputs L level when there is a carrier wave, and outputs H level when there is no carrier wave and only noise.
In addition, when the input terminal S of the RS flip-flop circuit 13 is at H level, the output terminal OUT is at H level,
When the input terminal RS is at H level, the output terminal OUT is at L level.

Figures 4a and 4b show the communication status and reception status of the transmitter/receiver 1A as the master unit, respectively.Currently, as shown in Figure 4d, transmission is being made from the transmitter/receiver 1A, and other indoor slave units are Assume that the transceiver 1B is in communication with the transceiver 1A as shown in FIG. 4e. On the other hand, until the call button of the transmitter/receiver 1C as a slave device for the entrance is pressed, the transmitter/receiver 1C is in an OFF state for both transmission and reception as shown in FIGS. 4(f) and 4(g). Now, when the transmitter/receiver 1A and 1B are talking, if the call button is pressed to call the master transmitter/receiver 1A from the transmitter/receiver 1C, the transmission will be sent simultaneously as shown in FIG. 4(h). The calling signal CS shown in is sent out redundantly. At this time, as shown in FIG. 4g, power is applied to the receiving circuit 3 of the transmitter/receiver 1C, but as shown in FIG. 4k, the mute circuit operates to turn off the audio circuit and no sound is output. That is, at this time, the reception block 11 instantaneously receives the carrier wave from the transceiver 1A and sets the squelch output of the squelch circuit to the L level. This L
The level squelch output becomes H level by the inverter circuit 16. At the same timing, the output of the AND circuit 14 becomes H level due to the H level calling signal from the calling block 6. Therefore, as shown in FIG. 4j, the RS flip-flop circuit 1
3 output terminal OUT becomes H level and OR circuit 15
The mute circuit of the receiving block 11 is activated via the transmitter/receiver 1A and 1B, and the audio of the conversation between the transmitter/receiver 1A and 1B is not output. In addition, on the transceiver 1A side, as shown in FIG.
The B side transmits the call to the 4th station based on the request from the transceiver 1A.
Truncate as shown in Figure e. At about the same time, on the transmitter/receiver 1A side, the fourth
As shown in Figure d, one-way transmission is turned off at time _t2 .
At this point, since the transmission from the transceiver 1A is turned off, the carrier wave cannot be received on the transceiver 1C side, so the squelch output becomes H level as shown in FIG. 4i. When the squelch output goes to H level,
Since a high level signal is input to the input terminal RS of the RS flip-flop circuit 13, the output terminal OUT is low.
level and tries to turn off the mute circuit. Therefore, this RS flip-flop circuit 13 has a function as a return means for inputting the signal to the input terminal RS and inverting the output terminal OUT to turn off the mute circuit. However, at this point, since the squelch output is at H level, the mute circuit is turned on via the OR circuit 15. switch
When the carrier wave is transmitted again from the transceiver 1A due to the return of the SW, the receiving block 11 of the transceiver 1C
In order to receive the carrier wave, the squelch output becomes L level, and at this time _t3 , the mute circuit is turned off, the audio circuit is turned on, and the audio received by the reception block 11 is output. Therefore, from time t 1 to time t ₂ shown in FIG. 4, from the time when the transmitter/receiver 1C sends out the calling signal CS, the time when the transmission from the transmitter/receiver 1A is temporarily turned off, and the time when the transmitter/receiver _1A transmits again.
During this time, the reception block 11 is muted by the mute circuit, so that the communication between the transceivers 1A and 1B does not leak to the calling transceiver.

The right side of FIG. 4 shows a mode in which a call is made by the slave transceiver 1C while the master transceiver 1A is on standby, not transmitting but only receiving data. That is, in response to the calling signal CS of the transmitter/receiver 1C, the transmitter/receiver 1C is
Power is applied to the transmitting circuit 2 and the receiving circuit 3 as shown in FIG. Since the receiving block 11 does not receive the carrier wave from the transmitter/receiver 1A, the squelch output becomes H level as shown in FIG. Turn it on and listen to it. On the transceiver 1A side, the call detection circuit 4 detects the signal CS' as shown in FIG. 4c, and the transceiver 1A recognizes and judges the call from the slave transceiver 1C. Send the message as shown to make the call possible.

As mentioned above, the specified invention is, when calling a transmitter/receiver having a master function from a transmitter/receiver having a slave function, the transmitter/receiver having the master function transmits waves to another transmitter/receiver having a slave function. a carrier wave detecting means for detecting a carrier wave inside the carrier; and a mute control circuit for cutting off the audio output of the receiving circuit of the calling side using the carrier wave detected by the carrier wave detecting means and the calling signal of the calling side. Since the device is installed in a transmitter/receiver with a slave device function, the carrier wave of the transmitter/receiver with a parent device function is detected by the carrier wave detecting means after the calling signal is transmitted from the transmitter/receiver with the slave device function. Using the carrier wave and the call signal from the calling side, the mute control circuit mutes and cuts off the audio output of the receiving circuit of the calling side, that is, the transmitter/receiver that has the slave function, and connects the transmitter/receiver with the master function to other children. This has the effect that the contents of a call with a transceiver having a slave function are not leaked to the calling side, which is the transmitter and receiver having a slave function.

In addition, in the case of a merged invention, when calling a transmitter/receiver having a master function from a transmitter/receiver having a slave function, the transmission of the transmitter/receiver having the master function to another transmitter/receiver having a slave function. A carrier wave detecting means for detecting a carrier wave in a wave, and a mute control circuit for cutting off the audio output of the receiving circuit of the calling side using the carrier wave detected by the carrier wave detecting means and the calling signal of the calling side. A call detection circuit of the transmitter/receiver with the master function detects a call signal from the transmitter/receiver with the slave function and interrupts the call with another transmitter/receiver with the slave function. A retransmission means for transmitting the carrier wave again is provided in the transmitter/receiver having the master function, and the retransmitted carrier wave is detected by the carrier detection means of the transmitter/receiver having the slave function, and the detection signal is used to output audio from the reception circuit. Since the above-mentioned mute control circuit is provided with a return means for returning the mute control circuit, when the transmitter/receiver having the master function is notified that it has been called, the call with the other transmitter/receiver having the slave function is terminated. Transmission is temporarily turned off, the retransmission means transmits again, the calling side detects the transmitted carrier wave, and the detected signal is used to restore the audio output of the receiving circuit by the restoring means of the mute control circuit. Therefore, after the transmitting/receiving device having the parent device function starts transmitting again, it is immediately possible to talk to the calling party, thereby improving convenience.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of the conventional example, Fig. 2 a to d are explanatory diagrams of the same operation, Fig. 3 is a block diagram of the embodiment of the present invention, and Figs. 4 a to k are explanatory diagrams of the same operation.
1A, 1B, 1C are transmitting and receiving devices, 2 is a transmitting circuit,
3 is a receiving circuit, 14 is a call detection circuit, and 5 is a mute control circuit.

Claims (1)

[Scope of Claims] 1. A transmitter/receiver having a master device function, which is composed of a transmitter/receiver having a master device function, and a plurality of transmitters/receivers each having a slave device function that can transmit and receive data to and from the master device having the master device function. The transmission frequency transmitted from the transmitter/receiver having the slave function is set at a first frequency, the transmitter frequency transmitted from the transmitter/receiver having the slave function is set at a second frequency different from the first frequency, and the transmitter/receiver having the master function is set at a second frequency different from the first frequency. The device includes a transmitting circuit that superimposes a calling signal on a carrier wave of the first frequency when calling a transceiver having a slave function, and a transmitting circuit that superimposes a calling signal on a carrier wave of the first frequency and transmits a second frequency transmitted from the transmitter and receiver having a slave function. A transmitter/receiver that is composed of a receiving circuit that receives sound and outputs audio, and a call detection circuit that detects a calling signal included in a carrier wave received by the receiving circuit, and has a slave function, has a master function. a transmitting circuit that superimposes and transmits a calling signal on the carrier wave of the second frequency when calling the transceiver having the transmitter and receiver; and a transmitting circuit that receives the first frequency transmitted from the transceiver having the parent device function and outputs audio. In a transmitting/receiving device configured with a receiving circuit, when calling a transmitter/receiver having a master function from a transmitter/receiver having a slave function, the transmitter/receiver having the master function is called by another transmitter/receiver having a slave function. carrier wave detection means for detecting a carrier wave being transmitted by the carrier wave, and a mute control circuit for blocking the audio output of the receiving circuit of the calling side using the carrier wave detected by the carrier wave detection means and the calling signal of the calling side. 1. A transmitting/receiving device characterized in that it is provided in a transmitting/receiving device having a transmitting/receiving function. 2 Consisting of a transmitter/receiver with a master device function and a plurality of transmitters/receivers with slave device functions that can transmit and receive data to and from the parent device, and the transmission frequency transmitted from the transmitter/receiver with the master device function. is set at a first frequency, the transmission frequency transmitted from the transmitter/receiver having the slave function is set at a second frequency different from the first frequency, and the transmitter/receiver having the master function is set at the slave function. a transmitting circuit that superimposes a calling signal on the carrier wave of the first frequency when calling the transceiver having the above-mentioned first frequency, and receives a second frequency transmitted from the transceiver having the slave device function and outputs audio. A transmitter/receiver having a slave function is configured to include a receiver circuit that detects a call signal included in a carrier wave received by the receiver circuit, and a call detection circuit that detects a call signal included in a carrier wave received by the receiver circuit. A transmitting circuit that superimposes a calling signal on a carrier wave of the second frequency and transmits the same, and a receiving circuit that receives the first frequency transmitted from the transmitter/receiver having a parent device function and outputs audio. In a transmitting/receiving device, when calling a transmitter/receiver having a master function from a transmitter/receiver having a slave function, the carrier wave being transmitted by the transmitter/receiver having the master function is transmitted to another transmitter/receiver having a slave function. A transmitter/receiver having the slave device function includes a carrier wave detection means for detecting a carrier wave, and a mute control circuit for cutting off the audio output of the receiving circuit of the calling side using the carrier wave detected by the carrier wave detection means and the calling signal of the calling side. The call detection circuit of the transmitter/receiver with the master function detects a call signal from the transmitter/receiver with the slave function, interrupts the call with another transmitter/receiver with the slave function, and then transmits the carrier wave again. Restoration in which a retransmission means for transmitting waves is provided in a transmitter/receiver having a master function, and the audio output of the receiving circuit is restored by a detection signal detected by the carrier wave detecting means of the transmitter/receiver having a slave function. A transmitting/receiving device characterized in that means is provided in the mute control circuit.