JPS6021665A - Communication system - Google Patents

Abstract

PURPOSE:To eliminate noise at the operation of a press-to-talk switch by bringing a receiver into the transmission operating state in response to a start signal from a transmitter and bringing the receiver into the reception operating state after a voice signal obtained by the demodulation of a carrier is not received. CONSTITUTION:When the press-to-talk switch 8 of a transmitter 3 is depressed, a start signal generating circuit 11 modulates a carrier C1 by a pulse code and drives a light emitting element 13 via a drive circuit 12. Then a voice circuit 14 modulates a carrier C2 with a voice signal from a microphone 9, drives the element 13 via the circuit 12 to irradiates an infrared-ray. A receiver receives 15 the infrared-ray, converts it into an electric signal, demodulates 18 the carrier C1 and detects 19 the start signal. The start signal sets an FF21, makes a transistor 22 conductive to drive a relay 24 and change over a switching circuit 25, and a voice signal demodulating 30 the modulation wave C2 is transmitted to the receiver 6 via the circuit 25 and the signal is converted into sound. In detaching the switch 8, after a prescribed time is elapsed by time constant circuits 35, 42 of the receiver, the FF21 is reset, the circuit 25 is changed over and the receiver is brought into the reception operating state.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a communication IC capable of transmitting and receiving audio signals using at least one pair of transmitting and receiving devices such as an intercom.

BACKGROUND TECHNOLOGY In such a NuID rental system, at least one of the transmitting/receiving devices installed in the room has a transmitter that transmits audio signals, and the wireless signal from this transmitter is installed at a fixed position H. The receiver receives the audio signal from the transmitter, and transmits the audio signal from the transmitter electrically to the receiver through the receiver to the connected transmitting/receiving device to convert the audio into sound. The audio signal from the other transmitting/receiving device is received by a receiving IC,
, I-C is configured to be acousticized. In the transmitter,
While the transmitter is transmitting audio data, the breath-talk switch provided on the transmitter remains operated.

In the prior art, by speaking while pressing the transmitter 4i['C' press talk switch, a 7 audio signal is transmitted to a receiver using infrared light or radio waves, and the receiver receives the audio signal. After transmitting a few words and transmitting them to the dragon's transmitting/receiving device, when the conversation is finished, the user releases the breath talk switch provided in the transmitter 1c and releases the hand. The end signal indicating the end is converted into a pulse code J114 and sent to the receiver 1 (after detecting this end signal 5-1, the receiver switches from the transmitting state to the receiving state. Such prior art Then, after the receiver VcJ? detects the termination signal f (for the first time, the receiver is in the receiving operation state 11!j, the termination signal is transmitted to the other transmitter/receiver during the transmitting operation state. The sound becomes audible and becomes noise.

OBJECTIVES An object of the present invention is to provide a wholesale price method that eliminates noise in the operation of a breath talk switch.

Embodiment FIG. 1 is an overall system diagram of an embodiment of the present invention. At least one of the pair of transmitting and receiving devices 1 and 2, 1, includes a transmitter 3 and a receiver 4. In this embodiment, the other transceiver device also includes a transmitter 5 and a receiver 6. Both receivers 4°6 are connected by line 7.

FIG. 2 is a block diagram of the transmitter 3. As shown in FIG. The transmitter 3 uses a breath talk switch 8 (!:%) which is suppressed for transmitting a message (!:% This breath talk switch 8'ft: talks while operating the breath talk switch 8'ft: and converts the talk into a + [ki signal]. The signal from the breath talk switch 8 is received and identified by the breath talk circuit 10.
As shown in FIG. 11), when the suppression operation is performed at times [1 and 2], the start signal generation circuit 11 converts the carrier wave into pulse codes l&n! Then, the driving cycle is F/1r12 to drive the residual light element 1B which emits infrared light. When the breath talk circuit 10 identifies that the breath talk switch 8 is being operated, the sweat voice circuit 14! The carrier wave is changed by 1'Δ by the audio signal of the microphone 9〃1, etc.
! The 14vJ circuit 12 drives the home light purple element 18.

The frequency C1 of the carrier wave which is also modulated by δ1t by the start signal and the same frequency C2 of the carrier wave modulated by the audio signal from the microphone 9 are set to be 1 so as to be different from each other.

FIG. 3 is a block diagram of the receiver 4. Light emitting element 13
The infrared light of Rikishima et al. is received by the light receiving element 15 and amplified by the first amplifier circuit 17. The receiving circuit 18
i! The start signal output circuit 19 identifies and receives the carrier wave having the IH wave number C1, and the start signal output circuit 19 detects the IH 11 after returning from 1) the opening price code, and transmits the signal from time t2 to time t4 as shown in FIG. 4 (2). A signal at medium high level is led out to line 20 and flip-flop 21 is set. The set output from the flip-flop 21 becomes high level at time t3 as shown in s,%J4i%(5). The output of this flip-flop 21 is connected via a resistor 27 to the bake of the C transistor 22 and via a diode 28 to the output of an AND gate 29.

At time t4, the transmission of the start signal ends, and instead of this, the carrier wave having frequency C2 is modulated by the audio signal,
It is detected by the receiving circuit 30.

The carrier wave detection signal having frequency C2 from this receiving circuit 30 is applied to a time constant circuit 35 including a resistor 81, a diode 82, a resistor 38, and an integrating capacitor 84. The voltage of the capacitor 84 in the time constant circuit 85vC2 is as shown in No. 41\I(3), and its output is level-discriminated by the discrimination level e1 of the inverting circuit 36. The output of the inverting port g886 is 1 as shown by No. 419141, and the output of the capacitor 34 is at the discrimination level e11.
At time t5 when c reaches time t5, the output of the 1-Z inversion W and 36 is given to one input of the AND gate 37, and the set output from the 7-return circuit 21 is passed through the diode 38 and the resistor 89. .40 and an integrating capacitor 41f: applied to an AND gate 37Vc via a time constant circuit 42 including an integral capacitor 41f. The output waveform from the capacitor 41 of this time constant circuit 42 is shown in FIG. 4 (6).
9, and the discrimination level of the AND gate 87 is referenced 12.
It is shown in The high level output of AND gate 37 resets flip-flop 21. This AND
The output from gate 37 is shown at the fourth +iz+17).

The carrier waves having the same wave number C1 are transmitted to the receiving circuit 1 as described above.
81c, and the detected signal is detected by the 41st M
1 [8). The output from this receiving circuit 18 is inverted by an inverting circuit 43 and applied to one of the AND gates 29. The output from the flip-flop 21 is applied to the AND gate 29vc. This flip-flop 21 is applied to the base of the ``c transistor or 22'' through the output cover and the resistor 27.The transistor 220 is connected to the base of the ``c'' transistor or 22 when the output of the AND gate 29 is U-level.
% control. Therefore, from time 4 onward, the transferer 22 becomes a conductive surface as shown in FIG. u! ``Since time t4, 1! φ, the relay coil 24 of relay 23 is energized, and this causes ls j sin f
i, % The switching mode of the relay switch 26 that has been sounded at 114525 i times changes. Therefore, the audio processing circuit Ij844 that demodulates the carrier wave having the same wave number C2
The voice signals from the voice signals from the switching circuit 25 are sent via the line 7 to the receiver 6 of the other transmitting/receiving device 2 IC (Itiii), where they are converted into sound t1X and put into a transmitting operation state.

At time I6, hand t- is pressed from breath talk switch 8.
When the signal is cut off by i, the transmission of the carrier wave having the same wave number C2 from the audio circuit 14 is stopped. As a result, the output of the receiving circuit 80 becomes low level, and the capacitor 34 of the time constant circuit 35 is connected to the resistor 38.
It is being done. At time t7 when the output of the capacitor 34 becomes less than the discrimination lever 921 of the inverting circuit 36, the output of the inverting circuit 36 becomes high level and the flip-flop 21 is reset. Therefore, the output of the flip-flop 210 set becomes the a-level as shown in FIG. 4(6). As a result, the capacitor 41 of the time constant circuit 42 is discharged by the resistor 40 and continues. In the time signal 8, the output of the capacitor r41 becomes less than the discrimination level Ie2 of the AND gate 37, and the output of the AND gate 37 becomes a low level 6. The base of transistor 220 is II',? k
lJ t 7 IC2 becomes a-level, transistor 22 is cut off, and relay coil 24 is demagnetized.

In this way, the relay switch 26 of one circuit 25 returns to its original switching mode. Therefore, the switching circuit 25 is
Returning to the receiving operation state 1, in which the voice signal from the receiver 26 can be audible by the speaker 45.

In this way, when the breath talk switch f is operated, the start signal (No. 8) is generated, and this start signal is detected and the IC audio signal is demodulated from C (!-
It becomes vc. Therefore, no noise is generated in the receiver 6 when operating the breathtalk switch. In addition, after the transmitter A stops operating the breathtalk switch 8 of 3 and shuts off, the IC transmitting operation state is stopped and, for example, one message is received, so when the operation of the breathtalk switch 8 is completed, a 1cfi sound is heard. In another embodiment of the present invention, the receiver 6 will not be used for a long time.Instead of detecting the carrier wave having the same wave number 02, the audio signal obtained by demodulating the carrier wave 7 is detected, After this audio signal is no longer detected, the I/O switch returns from the transmitting state to the receiving state.
You can do it.

Another embodiment of the present invention includes a transmitter 8 and a receiver 4.
The radio waves are replaced with infrared light (h).
& may be done.

Effects As described above, according to the present invention, it is possible to prevent ICI'Q g from occurring at the beginning and end of operation Vf of the breath talk switch.

[Brief explanation of the drawing]

The first part is an overall system diagram of an embodiment of the present invention, FIG. 2 is a block diagram of the transmitter 8, FIG. 3 is a block diagram of the receiving G4 (G, : This is a waveform group for explaining the operation of the AjjW example. 1.2... Transmitting/receiving device, 3.5... 迭偕(代), 4.
6...Receiver, 8...Breathtalk switch, 9.
...Microphone, 10...Breathtalk session B5. t
1...11F] Start signal generation circuit, 18... Remaining light element, 14... Audio circuit, 15... Light receiving element, ]7...
・Amplification circuit, 18.80...Reception circuit, 19...Start signal identification circuit, 21...Flip flop, 22.
...Transistor, 23...Relay, 25...Switching circuit, 85.42...Time constant circuit, 29.87...
・AND gate, 44...Voice spoon number N1.45...
・Speaker agent Patent attorney Kei Nishi

Claims (1)

[Scope of Claims] At least one pair of transmitting/receiving devices, at least one of each transmitting/receiving device, a transmitter for transmitting 500 times a number 9, and an audio signal transmitted therefrom. and send/receive the pond (
6+ a transmitting operation of transmitting a call via the device IC switching means;
LR4 includes a receiver that performs a receiving operation that converts the audio signal from the other transmitting/receiving device 1''l into an audio signal through its switching means; When the talk switch is operated, the receiver includes signal recovery means for detecting the initial PC start signal of the operation, and the receiver responds to the PC start signal by means of the one side change means to output the sending operation status. 1] J and other systems characterized in that the voice signal obtained by demodulating the carrier wave from the transmitter or the modulated carrier wave is no longer received and the receiving operation state is established after C.