JPH0522186A - Radio transmission/reception equipment - Google Patents

Abstract

PURPOSE:To receive the report of reception information of a transmission wave of each station from the other party station to automatically control the transmission level and the degree of modulation in each station. CONSTITUTION:One station A which receives the transmission wave from the other station B is provided with an other station information calculating circuit 1 which calculates the reception sensitivity to the transmission wave of the other station B and the degree of modulation of this transmission wave in accordance with reception signals IF and AF of the receiver of the station A and an information transmission circuit 2 which modulates calculated information with a standby tone as the subcarrier to transmit it to the other station A at the time of transmission of the station A. The other station B is provided with an information reception circuit 3 which receives this information from the station A after the end of speech and a setting circuit 4 which decodes this reception information to set the transmission output level and the degree of modulation of the transmission wave for next transmission. By this constitution, the power consumption of radio transmission/reception equipments which are portable or are mounted on vehicles and mutually communicate by the simplex system using the same radio frequency is reduced, and trouble that separation of user's mouth from a transmission-side microphone brings about shallow modulation to make the reception side difficult to hear at the time of handfree speech is prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio transmitter / receiver which is portable or vehicle-mounted and communicates with each other by a simplex method using the same radio frequency. In the wireless transmitter / receiver described above, the overall power consumption is reduced, and when talking in a hands-free manner, the microphone on the transmitting side is separated from the mouth and the modulation becomes shallow, making it difficult for the receiving side to hear, and too close to cause overmodulation. Measures for that are needed.

[0002]

2. Description of the Related Art A conventional radio transmitter / receiver (not shown) is, for example, an on-vehicle type, which detects the strength of the reception level with a so-called S meter, and the operator sees this to use a manual changeover switch to transmit power. The transmission power is controlled by switching the control voltage that determines the gain of the amplifier.

However, especially in the case of an on-vehicle type, since it is troublesome for the driver to operate the wireless device while driving the vehicle,
The actual situation is that the changeover switch is hardly used, although the meter is seen. On the other hand, the portable type has almost no S-meter, and the user cannot clearly judge the strength of the reception level simply by listening to the received voice signal, so in most cases, it is used in the highest output mode. Also, in the past, although there was a method of lowering the transmission output level of the local station by estimating the reception level from the other side, automatically control the transmission level and modulation degree by receiving the notification of the reception state from the other side. There was no formula.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a radio transmission / reception system having a system in which each station automatically controls the transmission level and the degree of modulation upon receiving notification of reception information for the transmission wave of its own station from the partner station. It is to realize the device.

[0005]

[Means for Solving the Problems]
When the simplex Breathtalk switch or the voice control switch that starts with the voice of the caller is OFF and the local station is receiving, the remote station keeps transmitting for a certain period of time to confirm that the remote station has finished transmitting. Paying attention to the fact that the method of transmitting tones of audible frequency at the time of standby after the end of the above is often used, the transmission wave from the partner station B is received as shown in the principle diagram of FIG. 1 showing the basic configuration of the present invention. Own station A
Is a receiver station information calculation circuit 1 that calculates the reception sensitivity of the receiver station B to the transmitted wave and the modulation factor of the transmitted wave from the received signals IF and AF of the receiver, and the calculated information When transmitting the
The information sending circuit 2 for sending to B
It is equipped with an information receiving circuit 3 that receives the above information from station A after the end of the call and a setting circuit 4 that decodes the received information and sets the transmission output level and the modulation degree of the transmission wave at the next transmission. It is achieved by the present invention.

[0006]

In the present invention, the partner station information calculation circuit 1 included in the own station A that receives the transmission wave from the partner station B receives the reception wave IF of the partner station B from the reception signal IF of the receiver of the own station A. The sensitivity is calculated, and the modulation of the transmitted wave of partner station B is calculated from the received signal AF. Then, the information transmission circuit 2 modulates the calculated information by using the standby tone as a subcarrier at the time of transmission of its own station A and transmits it to the other station B. The information receiving circuit 3 provided in the partner station B receives the above-mentioned information on the receiving sensitivity and the modulation degree from the station A after the call with the station A is terminated, and the setting circuit 4 decodes the received information and The transmission output level and the modulation degree of the transmission wave at the time of transmission are set. Therefore, the output level of the transmitted wave and the modulation factor at the time of the next transmission from the partner station B are set to the optimum values for reception by the own station A.

[0007]

FIG. 2 is a block diagram showing a circuit configuration of a radio transmitter / receiver according to an embodiment of the present invention, and FIG. 3 is a transmitter / receiver of its own station A and a transmitter / receiver of a partner station B for explaining the operation thereof. It is a figure which shows the telephone call state. Then, (1) of FIG. 4 shows an example of the frequency arrangement at the time of modulating the subcarrier of the standby tone in that embodiment, and (2) of FIG. 4 shows an example of the data put on the standby tone. In the block diagram of the embodiment of FIG. 2, the transceiver TR1 of the own station A and the transceiver TR of the partner station B
2 is the ON / OFF of each Breathtalk switch,
As shown in the state diagram of FIG. 3, simplex communication is alternately performed. The partner station information calculation circuit 1 provided in the receiver RX of the transceiver TR1 of the own station A is composed of a reception sensitivity detector 11 and a modulation degree detector 12, and that reception sensitivity detector 11 is the receiver RX. IF
The reception signal IF from the receiver unit B is extracted to calculate the reception sensitivity for the transmission wave of the transmitter TX of the partner station B, and the modulation degree detector 12 extracts the reception signal AF from the AF unit of the receiver RX and outputs the reception signal AF of the partner station B. Calculate the modulation of the transmitted wave. And the information transmission circuit 2
As shown in (1) of FIG. 4, when the information of the reception sensitivity and the modulation factor calculated above is transmitted from the local station A, for example, the center frequency is 1700 Hz.
Using the standby tone of as a subcarrier, the FM modulator in the IF section of the transmitter TX performs FM modulation with a frequency deviation Δf = 500 Hz and sends it to the partner station B. The information receiving circuit 3 provided in the receiver RX of the partner station B is the IF of the receiver RX after the end of the call with the station A.
From the receiver section, the information on the reception sensitivity that indicates the strength of the transmitted wave from station A from station A is extracted, and from the AF section of the receiver RX, from station A to station A
Information on the modulation factor of the transmitted wave of B is extracted and supplied to the setting circuit 4. The setting circuit 4 is composed of a transmission level setting device 41 and a modulation factor setting device 42, and the transmission level setting device 41 decodes the information of the transmission level of the destination taken out by the receiving circuit 3 and supplies it to the control section, and the ALC circuit. As shown in (2) of Fig.4, the 2-bit data 00,01,10,11 representing the signal strength of the output by controlling the gain of the power amplifier in the RF section of the transmitter TX
Set the output level of the transmitter at the next transmission to an appropriate value. Then, the modulation degree setter 42 decodes the information of the transmission modulation degree of the destination extracted by the receiving circuit 3 and, via the control section, the FM modulator of the IF section of the transmitter TX is shown in (2) of FIG. As described above, the modulation degree of the output wave of the transmitter TX at the time of the next transmission is set to an appropriate value by the 2-bit data 00, 01, 10, 11 representing the degree of the modulation degree. Therefore, the output level and the modulation factor of the transmission wave at the time of the next transmission from the transmitter of the partner station B are set to the optimum values for the reception of its own station A, and the power consumption due to the output level of the transmitter that is unnecessarily large is reduced. It is possible to avoid the increase, and it is also possible to avoid that the microphone on the transmitting side moves away from the mouth and the modulation becomes shallow and the receiving side becomes difficult to hear when talking in a hands-free manner.

[0008]

As described above, according to the present invention, the information on the reception state of the transmission wave transmitted by itself (B) is sent from the other party (A), and the transmitter of the next transmission is transmitted. Since the output level and the degree of modulation are automatically controlled and set to optimal values at all times, when two wireless stations are close to each other, each station can automatically reduce the output power of the transmitter and reduce the power consumption. Ready,
The effect that the life of the used battery can be extended can be obtained.
Further, since the modulation wave of the transmission wave is not overmodulated and the occupied frequency bandwidth of the transmission wave is not expanded, it is possible to obtain the effect of preventing interference with other communication systems.

[Brief description of drawings]

FIG. 1 is a principle diagram showing a basic configuration of a wireless transmission / reception device of the present invention.

FIG. 2 is a block diagram showing a circuit configuration of a wireless transmission / reception device according to an embodiment of the present invention.

FIG. 3 is a local station for explaining the operation of the embodiment of the present invention.
Diagram showing the call status between the transceiver of A and the transceiver of the partner station B,

FIG. 4 is a diagram showing an example of frequency arrangement when modulating a subcarrier of a standby tone and an example of data to be put on the standby tone according to the embodiment of the present invention;

[Explanation of symbols]

Reference numeral 1 is a partner station information calculation circuit in its own station A, 2 is an information transmission circuit, 3 is an information reception circuit in the partner station B, and 4 is a transmission output level and modulation degree setting circuit.

Claims (1)

What is claimed is: 1. When receiving the own station (A) of a method of communicating with each other by a simplex method, the other station (B) confirms the end of transmission for a certain period of time. In a radio transmitter / receiver that continues transmission and transmits audible frequency tones during standby after the call ends, the reception signal (IF) of the receiver is transmitted to the local station (A) that receives the transmission wave from the partner station (B). , AF) to partner station (B)
The receiving station information calculation circuit (1) for calculating the receiving sensitivity to the transmitted wave and the modulation degree of the transmitted wave, and the calculated information for that station (A)
The information transmission circuit (2) that modulates the standby tone as a subcarrier and transmits it to the partner station (B) when transmitting the information and the information received by the partner station (B) from the station (A) after the end of the call. Receiver circuit (3) and setting circuit that decodes the received information and sets the transmission output level and the modulation degree of the transmission wave at the next transmission
(4) A wireless transmission / reception device comprising: