JP2732584B2 - Transmission output production method and transmission output control device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission output control method and a transmission output control device in a wireless device performing press-talk type communication.

2. Description of the Related Art Conventionally, when performing press-talk type communication between a mobile station and a base station that continuously receives multi-channel frequencies, the transmission power of the base station is kept constant, and the transmission power of the mobile station is transmitted from the base station. Is controlled according to the reception level of the signal. Third
FIG. 1 shows the configuration of a mobile station-side radio apparatus employing this conventional transmission output control method. In the receiving state of the mobile station, a signal transmitted at a constant power from the base station is reproduced by the speaker 3 via the antenna 1 and the receiving unit 2, and the reception level at that time is detected by the reception level detection unit 4. The detected reception level is taken into the control unit 5. When the control unit 5 detects the ON operation of the press talk switch 6, the transmission unit 7
To the transmission state. At this time, the control unit 5 controls the transmission unit 7 to reduce the transmission power if the reception level captured from the reception level detection unit 4 is high in the previous reception state.
, And the transmitting unit 7 transmits via the antenna 1 with the controlled transmission power.

Problems to be Solved by the Invention In such a conventional configuration, it is necessary that one of the transmission powers is constant, and in the case of the above example, the base station:
Since high-power transmission is performed so that communication can be performed even at a short distance or a long distance, and this interferes with an adjacent same frequency zone, there is a problem that a communication channel cannot be used effectively.

The present invention provides a transmission output control method and a transmission output control device that can transmit at a high power only for a channel for long-distance communication and reduce transmission power for short-distance communication channels to improve channel reuse. The purpose is to do.

Means for Solving the Problems The transmission output control method and the transmission output control device of the present invention are configured such that, when performing a pre-stoke communication, one of the stations on the transmission side transmits transmission output value information together with an audio signal during transmission. The other station on the receiving side determines the state of the propagation path from the reception level and the transmission output value information, performs low-power transmission when it is determined to be short-range communication, and determines that it is long-range communication In this case, high power transmission is performed.

According to the method and the configuration, the state of the propagation path is determined from the transmission power value obtained from the output information and the reception level when communication is performed at the transmission power value, and the next transmission power is determined each time. Therefore, in short-distance communication, communication partners transmit low power to each other, and in long-distance communication, they transmit at maximum power to each other.

Embodiment Hereinafter, a transmission output control method and a transmission output control device of the present invention will be described based on specific embodiments.

FIG. 1 shows a state in which press-talk type communication is performed between a base station I and a mobile station II. In this example, both stations have the same wireless device configuration, and the transmission system of the base station I and the mobile station
The receiving system of II will be described.

When a call is made for the first time, each unit operates as follows. When the base station I gives the call code ID specifying the mobile station II of the other party to the control unit 8 and then turns on the pre-stalk switch 9, the control unit 8 instructs the transmission unit 10 to perform a transmission operation at the maximum power of 5W. At the same time, the switching unit 11 provided on the input side of the
, And the voice signal V from the transmitter 12 are sequentially given to the transmitter 10. This allows antenna 14
After that, as shown in FIG. 2, the call code ID and the voice signal V of the other party are transmitted at the maximum power of 5 W by turning on the pre-stalk switch 9.

In the mobile station II in the reception standby state, the transmission signal from the base station I is input to the receiving unit 16 via the antenna 15, and an incoming call is performed based on the call code ID of the other party input at the base station I. . At this time, the input detection unit 17 detects the reception level of the transmission signal from the base station I and inputs it to the control unit 18. The audio signal V sent from the base station I is a speaker 19
Will be played back.

When the call is ended and the pre-stalk switch 9 of the base station I is turned off, the control unit 8 switches the switch 11 and sends the synchronization signal PS and the calling code of the own station to the transmission unit 10 via the output code transmission unit 12. ID _o and given the output information P _i representing the transmit power for that time of the local station in turn, the base station I is switched to the receiving state after the end of these transmissions.

Calling code ID is transmitted from the base station I _o and the output information P _i is sent to the control unit 18 is detected by the output code detection unit 20 of the mobile station II. Note that the synchronization signal PS is detected and muted at the speaker connection unit 21 so that the synchronization signal PS, the call code _IDo , and the output information _Pi are not generated from the speaker 19. The control unit 18 of the mobile station II that has read this determines the transmission power toward the base station I as follows.

The other output information P _i that is input via the output code detecting unit 20 to the control unit 18, the reception level is read through the input detection unit 17 as described above. The control unit 18 outputs the output information P _i
The table shown in Table 1 below is written, in which the transmission power specified by (1) and the transmission power according to the reception level are specified.

The reception level read by the control unit 18 is evaluated by comparing it with preset level information. Here, the level information includes a reception input point S of 12 dB indicating a communication limit (SINAD), a reception input point A of 40 dB indicating a high quality state,
If the reception input point B is 60 dB indicating an excessive input state and the reception level of the signal from the base station I is not less than 20 dB and less than 40 dB, only the S among the reception input points S, A, and B is set with a flag. 1
00 ", the base station I given by the output information P _i =“ 01 ”
Output information P _i for instructing the same maximum power as transmission power 5W of =
“01” is provided to the transmission unit 22. In this case, the control unit 1
When 8 detects the ON operation of the press talk switch 23,
The transmission unit 22 performs transmission at a predetermined maximum output of 5 W.

Reception level of signal from base station I is 40dB or more respectively
In the state of less than 60dB and more than 60dB, instruct the transmission power 1W
P _i = “10”, P _i = “11” indicating transmission power of 0.2 W is the transmitting unit
Given to 22.

The transmission power is transmitted from the mobile station II while being controlled according to the state of the propagation path, and when the pre-talk switch 23 is turned off at the mobile station II, the transmission power is synchronized in the format shown in FIG. Signal, calling signal of own station I
D, output information _Pi is transmitted.

The table shown in Table 1 is also written in the control unit 8 of the receiving system of the base station I which has received the signal from the mobile station II, and similarly, the reception level of the signal of the mobile station II and the output information at that time
Next transmission power of the base station I, based on the P _i is determined, the transmission power is controlled.

When the base station I and mobile station II control the transmission output in three steps in 7 dB steps, the reference levels A and B of the reception input are used.
Each by the output information P _i to 7 dB, the level determined by 14dB changed. When the number of steps is three or more, or when the number of steps is changed to a value other than 7 dB, the number of steps is determined by comparing with a corresponding reference level. These received input information can be determined by the CPU by, for example, A / D converting the voltage. The signal from the receiving unit 16 to the input detecting unit 17 is temperature compensated by a known method.

Although described as changing the transmission power stepwise, the output information P _i a continuous display, it is possible to determine by comparing with continuous reference level.

Effects of the Invention As described above, according to the present invention, one station on the transmitting side transmits output information indicating its own transmission power before the end of transmission, and the other station on the receiving side transmits the output information. The station determines the next transmission power of its own station based on the reception level of the transmission signal from the one station and the output information, so that the stations communicating with each other are always controlled so as not to have excessive transmission power, It reduces interference to neighboring areas and is effective in channel reuse.

[Brief description of the drawings]

FIG. 1 is a block diagram of a radio apparatus of a base station and a mobile station showing a specific embodiment of a transmission power control method of the present invention, FIG. 2 is a format diagram of a transmission signal in the apparatus, and FIG. FIG. 2 is a configuration diagram of a wireless device. I: Base station, II: Mobile station, 8,18 ... Control unit, 9,23 ...
... Press talk switch, 10,22 ... Transmission unit, 17 ... Input detection unit, P _i ... Output information.

Claims (2)

(57) [Claims] At the time of performing a press-talk type communication, one station on the transmission side outputs transmission output value information together with an audio signal during transmission, and the other station on the reception side receives a reception level signal. And a transmission power control method for determining a state of a propagation path from the transmission output value information, performing low-power transmission when it is determined to be short-range communication, and performing high-power transmission when determining to be long-distance communication. 2. In performing a pre-stoke communication, one station on the transmitting side outputs transmission output value information together with an audio signal during transmission, and the other station on the receiving side outputs a reception level signal. A transmission power control device that determines the state of the propagation path from the transmission output value information and performs low-power transmission when it is determined to be short-range communication, and performs high-power transmission when it is determined to be long-range communication.