JPS6291029A - Two-way communication equipment - Google Patents

Abstract

PURPOSE:To prevent a transmitter/receiver of one side possible for movement from going to large size and expensive cost by operating a switch of the 2nd transmitter/receiver to send a control signal thereby switching line when a high frequency signal outputted from the 1st transmitter/receiver receives interferential disturbance. CONSTITUTION:If a high frequency signal outputted from a transmitter/receiver 33 receives interferential disturbance, it is detected by an interference detection circuit 27 of a transmitter/receiver 31 and sends a control signal to the transmitter/receiver 33 to switch there line thereby avoiding the interferential disturbance. Further, if the high frequency signal outputted from the transmitter/ receiver 31 receives interference/disturbance, a switch 43 of the transmitter/ receiver 33 is operated to send a control signal to the transmitter/receiver 31 thereby switching the line and preventing the interferential disturbance. Thus, large size and inexpensive cost of the movable transmitter/receiver are evaded and if any of both the transmitters/ receivers receives interferential disturbance in the high frequency output signal, it is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to a two-way communication device with an interference detection function.

BACKGROUND OF THE INVENTION In recent years, mobile radio communications have occupied an important position in the field of radio communications, and in particular, the proportion of radio communications connected to telephone lines, typified by car phones, cordless telephones, etc., is increasing. However, as long as wireless lines are used, interference is inevitable, and various methods are being considered for interference detection methods and line switching methods.

An example of the above-mentioned conventional two-way communication device will be described below with reference to the drawings. FIG. 2 is a block diagram of a conventional two-way communication device connected to a telephone line. In Figure 2, 1 is the input terminal from the telephone line, 2 is the input terminal 1
3 is a transmitter section which receives a low frequency signal from the controller 4 and a control signal from the controller 4 as modulation inputs, inputs the output of the local oscillator 5 as a local oscillation signal, and outputs a high frequency signal.
8 is the output terminal for transmitting the high frequency signal from the transmitter/receiver 1
2 is an input terminal for the high frequency signal from input terminal 8; 7 is a receiving section which receives the high frequency signal from input terminal 8 as a receiving input, inputs the output from local oscillator 5 as a local oscillation signal, and outputs a demodulated signal; 6 is a receiving section an interference detection circuit that receives the output from 7 as input, detects interference, and outputs an interference detection signal;
4 is an output terminal for outputting the demodulated output from the receiving section 7 to the telephone line, and 4 is the demodulated output from the receiving section 7 and an interference detection circuit 6.
The controller 5 inputs the interference detection signal from the controller 4 and outputs the control signal to the transmitter 2 and the line setting signal to the local oscillator 5; 11 is a line switching circuit comprising a control section 4 and a local oscillator 5, and IO is a transceiver connected to a telephone line. Further, 13 is an input terminal for a high frequency signal from the transceiver 10, and 14 is a receiving unit which receives the high frequency signal from the input terminal 13 as a reception input, and which inputs the output from the local oscillator 20 as a local oscillation signal and outputs a demodulated signal. , 15 is the receiving section 14
16 is an input terminal for a low frequency signal, 17 is a modulation input for the low frequency signal from the input terminal 16 and the control signal from the control section 19, and the local oscillator 2
0 is input as a local oscillation signal and outputs a high frequency signal; 18 is an output terminal for transmitting the high frequency signal from the transmitter 17; 19 is an output terminal to which the demodulated output from the receiver 14 is input; 17, and the local oscillator 2
0 is a control unit that outputs a line setting signal to 0, 20 is a control unit 19
a local oscillation circuit that inputs a line setting signal from the line setting signal and outputs a local oscillation signal in response to the line setting signal; 21 is a line switching circuit consisting of a control section 19 and a local oscillator 20;
is a mobile transceiver.

The operation of the transceiver configured as described above will be described below.

A low frequency signal input from the telephone line to the input terminal 1 is modulated by the transmitter 2 and becomes a high frequency signal, which is output from the output terminal 3 via a line specified by the controller 4. This high frequency signal is input to the input terminal 13 of the transceiver 12, demodulated by the receiving section 14, and then output as a demodulated output to the output terminal 15.The low frequency signal input to the input terminal 16 is input to the transmitting section 17. The modulated signal becomes a high frequency signal, and the control unit 1
The signal is output from the output terminal 18 via the line designated by 9. This high frequency signal is input to the input terminal 8 of the transceiver 10,
After being demodulated by the receiving section 7, it is output as a demodulated output to the output terminal 9 to the telephone line. Further, when the high frequency signal output from the output terminal 18 of the transceiver 12 is subjected to interference, the interference detection circuit 6 of the transceiver 10 detects it and outputs an interference detection signal to the control section 4. The control unit 4 sends out a control signal when the interference detection signal is input, and transmits the control signal to the transceiver 12.
After switching to another line, a line setting signal is output to the local oscillator 5 and the transceiver 10 is switched to the line to avoid interference.

(For example, "New Cordless Telephone" Facility Vo1.3
6. k3, P, P, 134-141) Problems to be Solved by the Invention However, in the above configuration, since the transmitter/receiver 12 does not have an interference detection function, no interference is output from the output terminal 3 of the transmitter/receiver 10. If a high frequency signal is subjected to interference, it cannot be avoided, and if an interference detection circuit is provided in the transmitter/receiver 12 to avoid the interference, the transmitter/receiver 12 becomes large and expensive. It had

In view of the above problems, the present invention avoids increasing the size and price of one of the movable transceivers, and when the high frequency output signal of either of the transceivers receives interference, the interference The purpose of the present invention is to provide a two-way communication device that can avoid this problem.

Means for Solving the Problems In order to solve the above problems, the two-way communication device of the present invention includes an interference detection circuit for detecting interference waves, and a first line switching circuit that receives the output of the interference detection circuit as an input. Equipped with a circuit,
Consisting of a first transceiver connected to a telephone line, and a second transceiver equipped with a second line switching circuit that has a switch and switches the line by operating the switch,
When there is an output from the interference detection circuit, the first line switching circuit is operated to switch the line of the first transceiver, and a control signal is sent to the second line switching circuit.
operates the line switching circuit to switch the line of the second transceiver, and when the switch is operated, operates the second line switching circuit to switch the line of the second transceiver. In addition to switching the line of the first transceiver, the first line switching circuit is operated by sending a control signal to switch the line of the first transceiver.

Effect of the present invention With the above-described configuration, when the high-frequency signal output from the second transceiver is subjected to interference, the interference detection circuit of the first transceiver detects it and sends a control signal to shut down the line. In addition, when the high frequency signal output from the first transceiver is subject to interference, the line is switched by operating the switch of the second transceiver and sending out a control signal. Therefore, even if the high frequency signal output from the first transceiver is subject to interference, the interference can be avoided by operating the switch.

Embodiment Hereinafter, a two-way communication device according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows a block diagram of a two-way communication device in one embodiment of the present invention. In FIG. 1, 22 is an input terminal from a telephone line, 23 is a modulation input of a low frequency signal from the input terminal 22 and a control signal from a control section 25, and the output of a local oscillator 26 is input as a local oscillation signal. , a transmitter that outputs a high frequency signal, 24 an output terminal that outputs a high frequency signal from the transmitter 23, and 29 a transceiver 3.
28 is an input terminal for the high frequency signal from input terminal 29, and 28 is a receiving section that receives the high frequency signal from input terminal 29 as a receiving input, and also inputs the output from the local oscillator 26 as a local oscillation signal, and outputs a demodulated signal. 27 is a receiving section An interference detection circuit receives the output from the receiver 28 as an input, detects interference waves, and outputs an interference detection signal; 30 is an output terminal that outputs the demodulated output from the receiver 28 to the telephone line; 25 is an output terminal from the receiver 28; A control section receives the demodulated output and the interference detection signal from the interference detection circuit 27, and outputs a control signal to the transmitting section 23 and a line setting signal to the local oscillator 26; 26 is a line setting signal from the control section 25; 32 is a control unit 25 which inputs a local oscillation signal and outputs a local oscillation signal corresponding to the line setting signal.
and a line switching circuit consisting of a local oscillator 26 and a local oscillator 26;
is a transceiver connected to a telephone line. Further, 34 is an input terminal for receiving a high frequency signal from the transceiver 31, and 35 is a reception terminal for receiving the high frequency signal from the input terminal 34, inputting the output from the local oscillator 41 as a local oscillation signal, and outputting a demodulated signal. 36 is an output terminal for the demodulated output from the receiving section 35, 37 is an input terminal for a low frequency signal, 38 is a modulation input for the low frequency signal from the input terminal 37 and the control signal from the control section 40, and a local oscillator. 'from 41'
A transmitter inputs the output as a local oscillation signal and outputs a high frequency signal; 39 is an output terminal for transmitting the high frequency signal from the transmitter 38; 40 is a demodulated output from the receiver 35 and a line switching request signal from the switch 43; Input and transmit section 3
8, and a local oscillation circuit 42 which receives a line setting signal from the control unit 40 and outputs a local oscillation signal in response to the line setting signal; 33 is a movable transmitter/receiver paired with the transmitter/receiver 31;

The operation of the two-way communication device configured as described above will be described below.

The low frequency signal input from the telephone line to the input terminal 22 is modulated by the transmitter 23 and becomes a high 1 wave signal, which is transmitted to the controller 2.
The signal is output from the output terminal 24 via the line designated by 5. This high frequency signal is input to the input terminal 34 of the transceiver 33, demodulated by the receiver 35, and then output to the output terminal 36 as a demodulated output. Furthermore, the low frequency signal input to the input terminal 37 is modulated by the transmitter 38 and becomes a high frequency signal.
The signal is output from the output terminal 39 via a line designated by the control unit 40. This high frequency signal is input to the input terminal 29 of the transceiver 31, demodulated by the receiving section 28, and then output as a demodulated output to the output terminal 30 to the telephone line. Here, if the high frequency signal output from the output terminal 39 of the transceiver 33 receives interference, the interference detection circuit 27 of the transceiver 31
and outputs an interference detection signal to the control section 25.

When the interference detection signal is input manually, the control unit 25 sends out a control signal, switches the transceiver 33 to another line, outputs a line setting signal to the local oscillator 26, switches the transceiver 31 to the line, Avoid interference interference.

Furthermore, if the high frequency signal output from the output terminal 24 of the transceiver 31 is subjected to interference, the person using the transceiver 33 will audibly recognize that the interference is occurring and turn the switch 43 on. When operated, a line switching request signal is output to the control section 40. When the line switching request signal is input, the control unit 40 sends out a control signal, switches the transceiver 31 to another line, outputs a line setting signal to the local oscillator 41, switches the transceiver 33 to the line, Avoid interference interference.

As described above, according to this embodiment, when the high frequency signal output from the transmitter/receiver [33 is subjected to interference interference, the transmitter/receiver 3
The interference detection circuit 27 of 1 detects interference and sends a control signal to the transmitter/receiver 33 to switch the line to avoid interference, and the high frequency signal output from the transmitter/receiver 31 receives interference. In this case, the switch 43 of the transmitter/receiver 33 is operated to send a control signal to the transmitter/receiver 31 to switch the line and avoid interference. Even if interference occurs, it can be avoided.

Furthermore, according to this method, a small and inexpensive interference detection circuit that detects only strong interference is used in the transceiver 31, and when the high frequency signal received by the transceiver 31 receives strong interference, the Interference detection circuit detects and avoids interference,
If the high-frequency signal is subject to weak interference, the person using the transceiver 31 will be able to hear the interference through the telephone line, and the person using the transceiver 33 will be able to It is possible to avoid interference by transmitting the information and operating the switch 43, and it is possible to make the transceiver connected to the telephone line smaller and lower in price. Note that interference detection can be realized by a method such as inserting a biloft signal outside the audio transmission band and detecting interference from distortion, jitter, etc. of the pilot signal after demodulation.

Effects of the Invention As described above, according to the present invention, it is possible to avoid the increase in size and price of one movable transmitter/receiver, and to prevent interference between the high-frequency output signals of either of the transmitters/receivers. It is possible to configure a two-way communication device that can avoid the interference when interference occurs.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a two-way communication device according to a first embodiment of the present invention, and FIG. 2 is a block diagram of a conventional two-way communication device. 22... Input terminal from telephone line, 23...
... Transmission section, 24... Output terminal, 25...
...Control unit, 26...Local oscillator, 27...
...Interference detection circuit, 28...Receiving section, 29
...Input terminal, 30...Output terminal to telephone line, 31...Transmitter/receiver, 32...
・Line switching circuit, 33... Transmitter/receiver, 34...
...Input terminal, 35...Receiving section, 36...
...Output terminal, 37...Input terminal, 38.
...Transmission section, 39...Output terminal, 40.
...control section, 41 ...local oscillator, 42
・・・・・・Line switching circuit. Name of agent: Patent attorney Toshio Nakao (1 person) Figure 1, Fort Figure 2

Claims (1)

[Claims] An interference detection circuit that detects interference waves and a first line switching circuit that receives the output of the interference detection circuit as an input, and has a first transceiver and a switch connected to a telephone line,
A second transmitter/receiver is provided with a second line switching circuit that performs line switching by operating the switch, and when there is an output from the interference detection circuit, the first line switching circuit is operated to switch the line. Switching the line of the first transceiver and operating the second line switching circuit by transmitting a control signal to switch the line of the second transceiver, and when the switch is operated, The second line switching circuit is operated to switch the line of the second transceiver, and the first line switching circuit is operated by transmitting a control signal to switch the line of the first transceiver. A two-way communication device characterized by switching.