JPH05160777A - Radio transmission power control system - Google Patents

Abstract

PURPOSE:To control a transmission power to be a proper level at all times by controlling automatically the transmission power level to be a proper level based on a reception level so as to avoid excess or deficiency of the transmission power of a radio terminal equipment. CONSTITUTION:A radio wave is sent from a radio communication center equipment 7 always at a prescribed power and received by radio terminal equipments 6a, 6b as a reception radio wave 101. The terminal equipments 6a, 6b measure the received audio wave level and control automatically the transmission power level of the station in use to a proper level based on a reception level. Or the S/N of the radio wave sent from the station in use is measured and the transmission power level is controlled to a proper level based on the result of measurement. Or the excess or deficiency of the transmission power of the station in use is controlled based on error detection information of the transmission data of the station in use at an opposite station. Or a distance between a location where the station in use is in existence and a location where the opposite station is in existence is recognized and the transmission power is automatically controlled to set the power to a proper level depending on the distance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wireless transmission power control system, and more particularly, to a wireless communication center device to eliminate excessive or excessive transmission power of a wireless terminal device which performs wireless communication under the control of the wireless communication center device. The present invention relates to a transmission power control method for automatically controlling to a minimum appropriate level that can be secured.

[0002]

2. Description of the Related Art Many wireless terminals of this type use a battery as a power source. Therefore, it is desirable that the transmission power be maintained at a minimum appropriate level for ensuring wireless communication with a partner station. The transmission power of a conventional wireless terminal device is always fixed at a constant level.

[0003]

In the above-mentioned conventional wireless terminal device, it is necessary to perform transmission / reception with the maximum power within the operating range so that communication can be performed at all places within the operating range where wireless communication is possible. The transmission power is set to a fixed value based on the location where it must be.

Therefore, even in a place where communication is possible with a small amount of power, unnecessary electric power radio waves are transmitted to unnecessarily consume electric power, and particularly in a wireless terminal device that supplies electric power with a battery. Has the drawback that it accelerates battery consumption due to unnecessary power consumption, reduces the operating time when the wireless terminal is actually used, and causes a great deal of opportunity loss for wireless terminal devices for public relations sales. ..

Further, when the transmission power is simply reduced to operate in order to extend the operating time, there is a drawback that wireless communication in a remote place cannot be normally ensured.

The object of the present invention is to eliminate the above-mentioned drawbacks, to extend the operating time of the wireless terminal device as the necessary and minimum proper power without suppressing the transmission power, by suppressing the excess and the excess, and the reliability of transmission and reception. It is to provide a wireless transmission power control method that can be operated so as to ensure the security.

[0007]

The structure of the present invention is a wireless transmission power control system for controlling the transmission power of a wireless terminal device that performs wireless communication under the general control of a wireless communication center device. Receives radio waves of constant power transmitted from the partner station, and automatically compresses or increases the transmission power level of its own station based on the reception level, and controls to the minimum appropriate level necessary for ensuring wireless communication. Or, obtain the S / N ratio of the radio wave transmitted by the local station, and maintain a constant S / N ratio at which the output of the radio wave transmitted by the local station becomes the minimum appropriate level necessary for ensuring wireless communication. Thus, it is configured to include means for controlling the transmission power of its own station.

Further, the system of the present invention is a wireless transmission power control system for controlling the transmission power of a wireless terminal device that performs wireless communication under the general control of a wireless communication center device, and the transmission data of the local station is the partner station. Whether or not it was correctly received is notified by the notification from the partner station, and if no transmission error is detected, it is transmitted with low power that can ensure wireless communication with the partner station,
When it is confirmed that a transmission error is detected, it is provided with a means for automatically controlling the transmission power so as to transmit at a high power that can ensure wireless communication with the partner station.

Further, the system of the present invention is a wireless transmission power control system for controlling the transmission power of a wireless terminal device which performs wireless communication under the generalization of a wireless communication center device, and determines the distance between the own station and the partner station. It is equipped with a means for measuring and automatically controlling the transmission power to the minimum appropriate level necessary for ensuring wireless communication based on the size of the distance from the partner station.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing the main configuration of the wireless terminal device according to the first embodiment of the present invention.

The wireless terminal device of the first embodiment shown in FIG. 1 comprises an antenna 1 for both transmission and reception, a reception radio wave level measuring unit 2 for measuring the level of the radio wave received by the antenna 1, and a radio radio wave for transmitting radio waves. The transmitter 3 includes a battery power source 4 and a transmission / reception switch 5.

In addition to the above-mentioned components, the actual wireless terminal device includes ordinary equipment circuits such as a reception processing system, a display system, and an operation system. In FIG. 1, these ordinary equipment circuits are described for convenience of explanation. Is omitted.

Next, the operation of the embodiment shown in FIG. 1 will be described.

Referring to FIG. 1, the received radio wave 101 is received by the antenna 1, becomes a received signal 103, and is input to the received radio wave level measuring unit 2.

The reception radio wave level measuring unit 2 measures the input level of the signal of the frequency used by the communication partner. The measurement result of measuring the level of the received radio wave 101 is output as the reception level signal 201, and the radio wave transmission unit 3
Provided to.

The radio wave transmitter 3 receives the reception level signal 20.
The transmission power is adjusted by 1 and the output signal 301 is output.

The output signal 301 is output from the antenna 1 as a transmission radio wave 102. The electric power of the received radio wave level measurement unit 2 and the radio wave transmission unit 3 is supplied from the battery power source 4.

Next, referring to the combination of FIG. 2 and FIG.
The operation of the first embodiment will be described in more detail.

As shown in FIG. 2, the wireless communication center device 71
Radio waves are always transmitted from the antenna 1 from the antenna 1,
The received radio wave 101 is received by the wireless terminal device (1) 6a and the wireless terminal device (2) 6b.

The received radio wave 101 is captured by the antenna 1 and input to the received radio wave level measuring section 2 as a received signal 103.

In the wireless terminal device (1) 6a, the measured value of the received electromagnetic wave level of the received electromagnetic wave level measuring unit 2 is point P shown in the characteristic diagram of FIG. 3, and in the wireless terminal device (2) 6b, the point Q. And All of these measured values are supplied to the radio wave transmission unit 3 of each wireless terminal device, and the wireless terminal device 6a sends out the transmission power indicated by point P in FIG. 3 and the wireless terminal device 6b sends out the transmission power indicated by point Q in FIG. ..

As described above, in the first embodiment, appropriate transmission power is sent out with excess and deficiency eliminated according to the received radio wave level. The characteristics shown in FIG. 3 are set in advance so as to obtain an appropriate level in consideration of the performance of the wireless terminal device, the peculiarity of the operating environment, and the like.

FIG. 4 is a block diagram showing the main configuration of the wireless terminal device according to the second embodiment of the present invention.

In the second embodiment, while the transmission power level is controlled based on the received radio wave level in the first embodiment described above, the transmission power level is controlled based on the S / N ratio of the radio wave transmitted from the own station. It is characterized by controlling the transmission power level.

The embodiment shown in FIG. 4 has an S / N ratio measuring section 8 for measuring the S / N ratio of a radio wave transmitted from its own station, and an S / N ratio.
A radio wave transmitting unit 9 for controlling the transmission power based on the measurement result of the ratio measuring unit 8 is provided, and the description of other components that the wireless terminal device normally has is the same as in the case of FIG. Omit it.

Next, the operation of the second embodiment shown in FIG. 4 will be described.

Referring to FIG. 4, the output of the radio wave transmission unit 9 is transmitted as a transmission radio wave 901 by using the antenna 1, is received by another antenna 1a of the own station, and the received signal 801 is S. An S / N ratio is measured by the A / N ratio measuring unit 8 and an excess / deficiency signal for controlling the transmission power so that the radio electric wave transmitting unit 9 can transmit at a constant S / N ratio is a radio electric wave transmitting unit. 9 is provided as a basic feature.

Next, the operation of the embodiment shown in FIG. 4 will be described in more detail with reference to FIG.

FIG. 5 (a) shows the received radio waves when the S / N ratio measuring section 8 measures the background noise signal received when the radio wave transmitting section 9 is not transmitting.

In FIG. 5, f indicates the frequency used in the radio wave transmitter 9, and A indicates the received power of background noise at that frequency.

Next, FIG. 5B shows received radio waves when the S / N ratio measuring section 8 measures the radio waves received while the radio wave transmitting section 9 is transmitting. The received power of the signal at the frequency f corresponding to FIG. 5 (a) is B. The S / N ratio is calculated by the values of A and B, and the signal is transmitted so that the signal can be transmitted at a constant S / N ratio. An electric power excess / deficiency signal is supplied to the radio wave transmitter 9.

When an excess / deficiency signal indicating that the transmission power is too large is transmitted, the radio wave transmitter 9 lowers the transmission power,
When an excess / deficiency signal indicating that the transmission power is too low is transmitted, the radio wave transmission unit 9 increases the transmission power.

In this way, a constant S / N ratio that keeps the transmission level at an appropriate level is maintained, and transmission power is controlled at an appropriate level without excess or deficiency.

FIG. 6 is a block diagram showing the configuration of the third embodiment of the present invention.

The third embodiment shown in FIG. 6 is basically characterized in that the transmission power of the own station is controlled based on the error detection information of the transmission data of the own station to be excessive or excessive. ， The structure is as follows.

That is, in the third embodiment shown in FIG.
The wireless terminal device 10 includes a transmission error detection unit 11 that detects an error in the received transmission data from the wireless communication center device 7.
And a radio wave transmission unit 12. Note that the description of other ordinary constituent elements of the wireless terminal device will be omitted as in the first and second embodiments.

Next, the operation of the third embodiment will be described.

Referring to FIG. 6, the wireless communication center device 7
And the wireless terminal device 10 communicate with each other, and the output of the wireless communication center device 7 is input to the transmission error detection unit 11 of the wireless terminal device 10 as a transmission radio wave 701 to demodulate a telegram from the wireless communication center device 7. .. If the demodulated data at that time is a resend request that specifies resending of the transmitted data,
The radio wave transmission unit 12 transmits a transmission power control signal for increasing the transmission power and eliminating the reception error of the wireless communication center device 7.
Then, the radio wave transmitting unit 12 receiving the control signal controls to increase the transmission power and transmits the signal.

Next, the operation of the third embodiment will be described in more detail with reference to FIG.

The transmission power in the radio wave transmitter 12 is
The initial value is set to low power.

The radio terminal device 10 includes a radio wave transmission unit 12
7 transmits the message 1 shown in FIG. The wireless communication center device 7 transmits to the wireless terminal device 10 a normal response indicating that the transmission radio wave 701 has been normally received.

The transmission error detection unit 11 demodulates the normal response data and informs the radio wave transmission unit 12 that the transmission power is appropriate.

The radio wave transmitter 12 keeps the transmission power as it is.

Next, the radio terminal unit 10 transmits the telegram 2 to the radio communication center unit 7 from the radio wave transmitting unit 12 with the transmission radio wave 1201.

If the wireless communication center device 7 cannot receive the data normally, the wireless communication center device 7 requests the wireless terminal device 10 to resend the data.
Tell. The transmission error detection unit 11 demodulates the data of the retransmission request, and informs the radio wave transmission unit 12 that the transmission power is insufficient.

The radio wave transmission unit 12 increases the transmission power and sends the telegram 2 again.

In this way, it is possible to control the transmission power to an appropriate level based on the quality of the reception state of the transmission data at the partner station, and to secure the wireless communication with the appropriate level of transmission power that is sufficient.

FIG. 8 is a block diagram showing the configuration of the fourth embodiment of the present invention.

The wireless terminal device of the fourth embodiment shown in FIG. 8 includes a distance detecting section 13 for detecting the distance to the communication partner station,
The radio wave output unit 14 has a transmission power level controlled by a transmission power control signal output from the distance detection unit 13.

It should be noted that, in FIG. 8, the description of the ordinary constituent elements of the wireless terminal device is omitted as in the first to third embodiments.

In the fourth embodiment, the distance between the place where the own station exists and the place where the communication partner station exists is known, and the transmission power is automatically controlled according to the size of this distance to obtain an appropriate level. It is what

Next, the operation of this embodiment will be described with reference to FIGS. 9 and 10.

Here, the wireless terminal device (1) shown in FIG.
The case where 6a performs wireless communication with the wireless communication center device 7 is taken as an example.

The wireless communication center device 7 sends / notifies the time information A shown in FIG. 9 from the antenna 71 to the wireless terminal device (1) 6a. On the other hand, from the time information transmitting station 15, FIG.
At the same time as the time information A from the antenna 151, the time information B shown in is transmitted and notified to the wireless terminal device (1) 6a.

The wireless terminal device (1) 6a includes the distance detecting unit 1
3 obtains the reception time difference T between the time information A and the time information B, and calculates the distance to the wireless communication center device 7 from this reception time difference T. Small power is used when the distance is short, and high power is used when the distance is long. Then, a transmission power control signal for controlling to be transmitted in step 1 is transmitted to the radio wave output unit 14. In this way, it becomes possible to automatically control the transmission power level based on the distance from the communicating station.

The first to fourth embodiments described above are
Although shown as four examples applied to each independently,
It is obvious that these functions can be easily implemented by appropriately combining them into each wireless terminal device.

[0058]

As described above, the reception level, S /
Achieve wireless communication with the minimum required power at an appropriate level by automatically adjusting the transmission power level to an appropriate value that can be received by the communication partner, depending on the N ratio, reception status of the communication partner station, and distance. In a wireless terminal device that supplies power with a battery, it is possible to improve communication reliability and prevent unnecessary battery consumption.

Further, since transmission is always performed with proper transmission power that is neither excessive nor excessive, there is an effect that the reliability of transmission and reception can be improved.

[Brief description of drawings]

FIG. 1 is a block diagram showing a main configuration of a wireless terminal device according to a first embodiment of the present invention.

FIG. 2 is a diagram showing an example of an operating state of the embodiment of FIG.

FIG. 3 is a transmission / reception level characteristic diagram showing an example of transmission / reception levels in the embodiment of FIG.

FIG. 4 is a block diagram showing a main configuration of a wireless terminal device according to a second embodiment of the present invention.

5 is a frequency characteristic diagram showing an example of received radio wave power in the embodiment of FIG.

FIG. 6 is a block diagram showing a main configuration of a wireless terminal device according to a third embodiment of the present invention.

FIG. 7 is a diagram showing an example of transmission of transmission radio waves and transmission of response radio waves in the embodiment of FIG.

FIG. 8 is a block diagram showing a system configuration in a fourth embodiment of the present invention.

9 is a diagram showing an example of reception time information in the embodiment of FIG.

FIG. 10 is a diagram showing an example of an operating state of the embodiment of FIG.

[Explanation of symbols]

 1, 1a Antenna 2 Received radio wave level measurement unit 3 Radio wave transmission unit 4 Battery power supply 5 Transmission / reception switch 6a Radio terminal device (1) 6b Radio terminal device (2) 7 Radio communication center device 8 S / N ratio measurement unit 9 Radio Radio wave transmitter 10 Wireless terminal device 11 Transmission error detector 12 Radio wave transmitter 13 Distance detector 14 Radio wave output unit 15 Time information transmitter

Claims (3)

[Claims] 1. A wireless transmission power control method for controlling the transmission power of a wireless terminal device that performs wireless communication under the general control of a wireless communication center device, wherein a fixed power transmitted from a partner station that performs wireless communication is controlled. Receives radio waves and automatically compresses or increases the transmission power level of its own station based on the reception level to control to the minimum appropriate level necessary for ensuring wireless communication, or to transmit radio waves of its own station. Radio wave S /
A means is provided for controlling the transmission power of the own station so as to obtain the N ratio and maintain a constant S / N ratio at which the output of the transmission radio wave of the own station becomes the minimum appropriate level necessary for ensuring wireless communication. A wireless transmission power control method characterized by comprising: 2. A wireless transmission power control method for controlling transmission power of a wireless terminal device performing wireless communication under the general control of a wireless communication center device, wherein transmission data of a local station is accurately received by a partner station. Whether or not there was a transmission error was detected, and if no transmission error was detected, it was sent with low power that could ensure wireless communication with the other station, and it was confirmed that a transmission error was detected. In this case, the wireless transmission power control method is provided with means for automatically controlling the transmission power so as to transmit at a high power that can ensure wireless communication with the partner station. 3. A wireless transmission power control method for controlling the transmission power of a wireless terminal device that performs wireless communication under the general control of a wireless communication center device, wherein the distance between the own station and the other station is measured and the other station is measured. A wireless transmission power control method comprising means for automatically controlling the transmission power to a minimum appropriate level necessary for ensuring wireless communication based on the size of the distance from