JPH11284569A - Transmission power control system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transmission power control system which is not affected by a radio wave propagation state on a radio communication line. SOLUTION: Data received through an antenna and a sharing device 30 undergoes demodulation processing, in a demodulation processing part 21 and is subjected to decoding processing in a decode processing part 22. A BER measuring part 50 calculates a bit error rate of the decoded data. When the bit error rate is less than prescribed value, transmission power value is increased or reduced, based on the information of transmission power control information B stored in a receiving packet, and data transmission is performed. Also, when the bit error rate is equal to the prescribed value or more, it is decided that a radio wave propagation state on a radio communication line is poorly received, and that the reliability of the received packet itself is low, the information of the information B being stored in the received packet is ignored, and data transmission is performed with the transmission power of the preceding transmission as it is.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a transmission power control system for a cellular mobile communication system for performing two-way communication.

[0002]

2. Description of the Related Art In radio communication of a digital cellular phone or the like, bidirectional communication is performed by setting a radio channel between a base station having a transmitter and a receiver and a mobile station having a transmitter and a receiver. In order to keep the signal quality constant, appropriate transmission power control is performed. As this transmission power control method, an average C within a certain time t for a wireless communication channel is used.
The IR (desired wave to interference wave power ratio) is measured, and if the average CIR is equal to or more than a predetermined value, the base station (mobile station) sends a command to reduce the transmission power to the mobile station (base station). The mobile station (base station) that has received this command immediately decreases its transmission power by a predetermined width, and if the average CIR is less than a predetermined value, the base station (mobile station) increases the transmission power. A transmission power control method is disclosed in Japanese Patent Application Laid-Open No. H5-244056, in which the mobile station (base station) that has received the command to cause the mobile station (base station) to receive the command immediately increases its transmission power by a predetermined width. No. 6,009,036.

[0003]

In a wireless communication line, the state of radio wave propagation often deteriorates due to noise or the like. In the above-mentioned conventional technology, depending on the state of radio wave propagation in a wireless communication line, a bit error, a frame error or the like may occur. Occur frequently, and the reliability of received data is reduced, the transmission power is increased or decreased according to the transmitted transmission power control command.

However, according to the conventional technique, there is a possibility that the received data can be received even if the received data is erroneous. Since it is determined that the command to reduce the power has been transmitted and the transmission power is reduced, there is a problem that the wireless channel is disconnected.

The present invention has been made in view of the above problems, and provides a transmission power control method which is not affected by a radio wave propagation state on a radio communication line.

[0006]

According to a first aspect of the present invention, there is provided an apparatus for performing transmission power control by transmitting and receiving a transmission power control command. It is characterized by performing non-compliant control. In claim 2, in a device that performs transmission power control by transmitting and receiving a transmission power control command, means for measuring a bit error rate of received data is provided, and when the bit error rate is equal to or more than a predetermined value, The transmission power control command is ignored.

According to a third aspect of the present invention, there is provided an apparatus for performing transmission power control by transmitting and receiving a transmission power control command, comprising means for measuring a bit error rate of received data, wherein the bit error rate is not less than a predetermined value. In this case, the transmission power value is increased by a predetermined value. According to a fourth aspect of the present invention, in a device for performing transmission power control by transmitting and receiving a transmission power control command, means for measuring a frame error rate of received data is provided,
When the frame error rate is equal to or more than a predetermined value, the transmission power control command is ignored.

According to a fifth aspect of the present invention, there is provided an apparatus for performing transmission power control by transmitting and receiving a transmission power control command, comprising means for measuring a frame error rate of received data, wherein the frame error rate is not less than a predetermined value. In this case, the transmission power value is increased by a predetermined value. In claim 6, in a device for performing transmission power control by transmitting and receiving a transmission power control command,
A means for measuring a CIR value of a received signal is provided, and when the CIR value is equal to or more than a predetermined value, the transmission power control command is ignored.

According to a seventh aspect of the present invention, there is provided an apparatus for performing transmission power control by transmitting and receiving a transmission power control command, comprising means for measuring a CIR value of a received signal, wherein the CIR value is equal to or more than a predetermined value. The transmission power value is increased by a predetermined value.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an apparatus using a transmission power control system according to the present invention will be described with reference to the drawings. First, a first embodiment will be described with reference to FIGS. FIG. 1 is a functional block diagram of a communication control unit according to the first embodiment, which is incorporated in a base station and a mobile station of a mobile phone. In the present embodiment, description will be made on the assumption that the information to be transmitted is audio data.

As for the flow of a voice signal during a call, a voice signal input from a microphone or the like (not shown) on the mobile station side is digitized via an A / D converter (not shown) or the like, and encoded by a code processing unit 11. Is applied. The data encoded by the code processing unit 11 is input to the modulation processing unit 12 and subjected to modulation processing. The data modulated by the modulation processing unit 12 is input to the amplification processing unit 13 and subjected to amplification processing. The data amplified by the amplification processing unit 13 is transmitted from the antenna to the wireless communication channel via the duplexer 30.

On the base station side, the signal is received by the antenna and input to the demodulation processing section 21 via the duplexer 30 to be subjected to demodulation processing. The data demodulated by the demodulation processing unit 21 is input to the decoding processing unit 22 and subjected to decoding processing.
The data decoded by the decoding processing unit 22 is output as a digital audio signal, and the subsequent processing is performed.
It is to be noted that the subsequent processing will not be described in detail.

The digital audio signal from the base station is subjected to an encoding process in an encoding unit 11. The data encoded by the code processing unit 11 is transmitted to the modulation processing unit 12
And is subjected to modulation processing. The data modulated by the modulation processing unit 12 is input to the amplification processing unit 13 and subjected to amplification processing based on the transmission power value. Amplification processing unit 13
Is transmitted from the antenna to the wireless communication channel via the duplexer 30.

On the mobile station side, the signal is received by the antenna and input to the demodulation processing unit 21 via the duplexer 30 to be subjected to demodulation processing. The data demodulated by the demodulation processing unit 21 is input to the decoding processing unit 22 and subjected to decoding processing.
The data decoded by the decoding processing unit 22 is output as a digital audio signal, and is output as audio via a D / A converter, a speaker, and the like (not shown).

On the mobile station side and the base station side, the data decoded by the decoding processing section 22 is transmitted to the BER measuring section 5.
It is also input to 0. The BER measuring unit 50 takes in the error-correction-encoded data in the code processing unit 11 of the partner via the decoding processing unit 22 and calculates a bit error rate (BER). As for data on the wireless communication channel, packets shown in FIG. 2 are transmitted and received. This packet includes a synchronization signal A, transmission power control information B, data, and frame error check information C. The synchronization signal A is
The signal for synchronizing the wireless communication, the transmission power control information B is a signal indicating command information for decreasing or increasing the transmission power, the data stores voice information and the like, and the frame error check information C is a packet This is an information signal for checking its own error.

The above-mentioned processing units are controlled by a main control unit 40. The main control unit 40 is composed of a ROM, a RAM, a CPU, etc., storing various control processing programs and the like. Next, a first embodiment of the transmission power control in the above configuration will be described based on the flowchart of FIG. In the present embodiment, a description will be given as processing on the mobile station side.

In step S11, the received packet transmitted from the base station via the antenna, the duplexer 30, the demodulation processing unit 21, and the decoding processing unit 22 is sent to the BER measurement unit 5
The value is taken into 0, the bit error rate is calculated, and supplied to the main control unit 40. This bit error rate is obtained in the process of correcting a received packet for errors. In step S12, it is determined whether or not the bit error rate obtained in step S11 is equal to or greater than a predetermined value. If it is determined that the bit error rate is equal to or greater than the predetermined value, the process proceeds to step S
Proceeding to step S15, if it is determined that the bit error rate is less than the predetermined value, the procedure proceeds to step S13.

In step S13, it can be determined that the bit error rate is small, the radio wave propagation state on the wireless communication line is good, and the reliability of the received packet itself is high, and the transmission power stored in the received packet is determined. Based on the information of the transmission power control information B which is a control command, a setting for increasing or decreasing the transmission power from the mobile station is performed, and the process proceeds to step S14. For example, if the instruction is to increase the information of the transmission power control information B, the transmission power value of the amplification processing unit 13 is increased,
If the instruction is a decrease instruction, the transmission power value of the amplification processing unit 13 is decreased.

In step S15, since the bit error rate is high, the radio wave propagation state on the wireless communication line is poor, and it can be determined that the reliability of the received packet itself is low, and the transmission stored in the received packet is not performed. The information of the transmission power control information B, which is the power control command, is ignored, the transmission power value of the amplification processing unit 13 is kept at the same value in step S16, and the process proceeds to step S14. That is, the transmission power at the time of the previous transmission is maintained.

In step S14, at the time of transmission, wireless communication is performed based on the transmission power value set in the amplification processing unit.
This makes it possible to prevent disconnection of the wireless channel due to erroneous transmission power control instructions. That is,
Data transmission not affected by the radio wave propagation state on the wireless communication line becomes possible. In step S15, the information of the transmission power control information B, which is the transmission power control command, is ignored, and the process proceeds to step S16. Step S17 indicated by
You may make it go to. That is, in step S15, since the bit error rate is high, it can be determined that the radio wave propagation state on the wireless communication line is bad, and the packet transmitted from the mobile station side is more likely to have a bit error. In step S17, the transmission power value of the amplification processing unit 13 is increased by a predetermined value and set irrespective of the transmission power control command, and the process proceeds to step S14.

Thus, there is a high possibility that the packet transmitted from the mobile station will be transmitted as normal data even if the radio wave propagation state on the radio communication line is poor. Next, a second embodiment will be described with reference to FIGS. 2, 4, and 5. FIG. FIG. 4 is a functional block diagram of a communication control unit according to the second embodiment, which is incorporated in a base station and a mobile station of a mobile phone. In the present embodiment, description will be made on the assumption that the information to be transmitted is audio data.

The flow of a voice signal during a call is the same as that in the first embodiment, and the components denoted by the same reference numerals as those in FIG. 1 perform the same operations and will not be described in detail.
As for the data on the wireless communication channel, the packet shown in FIG. 2 is transmitted and received in the same manner as in the first embodiment. In the communication control units provided on the mobile station side and the base station side, the data decoded by the decoding processing unit 22 is also input to the CRC measurement unit 60. The CRC measurement unit 60 captures the frame error check C attached to the last part of the received packet via the decoding processing unit 22, and calculates the packet frame error rate. This packet frame error rate is obtained by determining how many packet frame errors have occurred during a fixed reception period.

Next, a second embodiment of the transmission power control in the above configuration will be described with reference to the flowchart of FIG. In the present embodiment, a description will be given as processing on the mobile station side. In step S21, the antenna and the duplexer 3
0, the received packet transmitted from the base station is taken into the CRC measuring unit 60 via the demodulation processing unit 21 and the decoding processing unit 22, the packet frame error rate is calculated, and supplied to the main control unit 40. .

In step S22, step S21
Then, it is determined whether or not the packet frame error rate obtained in is greater than or equal to a predetermined value set in advance. If it is determined that the packet frame error rate is equal to or more than the predetermined value, the process proceeds to step S
The process proceeds to step S25, and if it is determined that the packet frame error rate is less than the predetermined value, the process proceeds to step S23. In step S23, it can be determined that the packet frame error rate is low, the radio wave propagation state on the wireless communication line is good, the reliability of the received packet itself is high, and the transmission power control command stored in the received packet is determined. Is set to increase or decrease the transmission power from the mobile station based on the information of the transmission power control information B, and the process proceeds to step S24. For example, if the instruction is to increase the information of the transmission power control information B, the transmission power value of the amplification processing unit 13 is increased. If the instruction is to decrease the transmission power value, the transmission power value of the amplification processing unit 13 is decreased.

In step S25, since the packet frame error rate is high, the radio wave propagation state on the wireless communication line is poor, and it can be determined that the reliability of the received packet itself is low, and the packet is stored in the received packet. Ignore the information of the transmission power control information B which is the transmission power control command, and
At 26, the transmission power value of the amplification processing unit 13 is kept as it is, and the process proceeds to step S24. That is, the transmission power at the time of the previous transmission is maintained.

In step S24, at the time of transmission, wireless communication is performed based on the transmission power value set in the amplification processing unit.
This makes it possible to prevent disconnection of the wireless channel due to erroneous transmission power control instructions. That is,
Data transmission not affected by the radio wave propagation state on the wireless communication line becomes possible. In step S25, the information of the transmission power control information B, which is the transmission power control command, is ignored, and the process proceeds to step S26. Step S27 indicated by
You may make it go to. That is, in step S25, since the packet frame error rate is high, it can be determined that the radio wave propagation state on the wireless communication line is poor, and the packet transmitted from the mobile station also has a high possibility of error. In step S27, the transmission power value of the amplification processing unit 13 is increased by a predetermined value and set irrespective of the transmission power control command, and the process proceeds to step S24.

Thus, a packet transmitted from a mobile station is more likely to be transmitted as normal data even if the radio wave propagation state on the radio communication line is poor. Next, a third embodiment will be described with reference to FIGS. 2, 6, and 7. FIG. FIG. 6 is a functional block diagram of a communication control unit according to the third embodiment incorporated in a base station and a mobile station of a mobile phone. In the present embodiment, description will be made on the assumption that the information to be transmitted is audio data.

The flow of a voice signal during a call is the same as that in the first and second embodiments, and those denoted by the same reference numerals as those in FIG. 1 perform the same operations. Do not state. The data on the wireless communication channel is the first data.
Similarly to the second embodiment, the packets shown in FIG. 2 are transmitted and received. In the communication control units provided on the mobile station side and the base station side, the data demodulated by the demodulation processing unit 21 is also input to the level measurement unit 70. The level measuring unit 70 calculates a carrier-to-interference ratio (CIR) by measuring the received signal level and the interference level.

Next, a third embodiment of the transmission power control in the above configuration will be described with reference to the flowchart of FIG. In the present embodiment, a description will be given as processing on the mobile station side. In step S31, the antenna and the duplexer 3
0, via the demodulation processing unit 21, the data sent from the base station is taken into the level measurement unit 70, the average CIR for the radio communication channel within a certain period is calculated, and supplied to the main control unit 40. .

In step S32, step S31
Then, it is determined whether or not the CIR obtained in step is equal to or higher than a predetermined level value. If it is determined that the CIR is equal to or higher than the predetermined level value, the process proceeds to step S33. If it is determined that the CIR is lower than the predetermined level value, the process proceeds to step S33.
Proceed to 35. In step S33, the CIR is high,
The radio wave propagation state on the wireless communication line is good, and it can be determined that the reliability of the received packet itself is high. Based on the information of the transmission power control information B, which is the transmission power control command stored in the received packet, The setting for increasing or decreasing the transmission power from the station is performed, and the process proceeds to step S34. For example, if the instruction is to increase the information of the transmission power control information B, the transmission power value of the amplification processing unit 13 is increased. If the instruction is to decrease the transmission power value, the transmission power value of the amplification processing unit 13 is decreased.

In step S35, since the CIR is low, the radio wave propagation state on the wireless communication line is poor, and it can be determined that the reliability of the received packet itself is low, and the transmission power control stored in the received packet is determined. The information of the transmission power control information B, which is the command, is ignored, and the transmission power value of the amplification processing unit 13 is held as it is in step S36, and the process proceeds to step S34. That is, the transmission power at the time of the previous transmission is maintained.

In step S34, at the time of transmission, wireless communication is performed based on the transmission power value set in the amplification processing unit.
This makes it possible to prevent disconnection of the wireless channel due to erroneous transmission power control instructions. That is,
Data transmission not affected by the radio wave propagation state on the wireless communication line becomes possible. In step S35, the information of the transmission power control information B, which is the transmission power control command, is ignored, and the process proceeds to step S36. Step S37 indicated by
You may make it go to. That is, in step S35, since the CIR is low, it is possible to determine that the radio wave propagation state on the wireless communication line is poor, and it is highly likely that an error will occur in data transmitted from the mobile station side.
Amplification processing unit 1 regardless of transmission power control command
3 is increased by a predetermined value and set, and the process proceeds to step S34.

Thus, a packet transmitted from a mobile station is more likely to be transmitted as normal data even if the radio wave propagation state on the radio communication line is poor. As described above, in the first to third embodiments, the processing has been described as the processing of the mobile station. However, the same processing is performed in the processing of the base station.

[0034]

According to the present invention, data transmission can be performed without being affected by radio wave propagation conditions on a radio communication line, and erroneous transmission power control of received data caused by a bad radio wave propagation state on a radio communication line. Disconnection of the wireless channel by following the instruction can be prevented.

Also, a packet transmitted from the device is more likely to be transmitted as normal data even if the radio wave propagation state on the wireless communication line is poor.

[Brief description of the drawings]

FIG. 1 is a functional block diagram of a communication control unit for explaining a first embodiment of the present invention.

FIG. 2 is a schematic diagram showing an embodiment of a packet transmitted and received on a wireless communication channel.

FIG. 3 is a flowchart illustrating a first embodiment of the present invention.

FIG. 4 is a functional block diagram of a communication control unit for explaining a second embodiment of the present invention.

FIG. 5 is a flowchart illustrating a second embodiment of the present invention.

FIG. 6 is a functional block diagram of a communication control unit for explaining a third embodiment of the present invention.

FIG. 7 is a flowchart illustrating a third embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Code processing part 12 Modulation processing part 13 Amplification processing part 21 Demodulation processing part 22 Decoding processing part 30 Duplexer 40 Main control part 50 BER measurement part 60 CRC measurement part 70 Level measurement part A Synchronization signal B Transmission power control information C Frame error Check signal

Claims (7)

[Claims] 1. An apparatus for performing transmission power control by transmitting and receiving a transmission power control command, wherein the apparatus performs control not in accordance with the transmission power control command based on a state on a communication line. method. 2. An apparatus for performing transmission power control by transmitting and receiving a transmission power control command, comprising means for measuring a bit error rate of received data, wherein the bit error rate is equal to or more than a predetermined value. A transmission power control method characterized by ignoring a transmission power control command. 3. An apparatus for performing transmission power control by transmitting and receiving a transmission power control command, comprising means for measuring a bit error rate of received data, wherein when the bit error rate is equal to or more than a predetermined value, transmission is performed. A transmission power control method characterized by increasing a power value by a predetermined value. 4. An apparatus for performing transmission power control by transmitting and receiving a transmission power control command, comprising means for measuring a frame error rate of received data, wherein the frame error rate is equal to or more than a predetermined value. A transmission power control method characterized by ignoring a transmission power control command. 5. An apparatus for performing transmission power control by transmitting and receiving a transmission power control command, comprising: means for measuring a frame error rate of received data; A transmission power control method characterized by increasing a power value by a predetermined value. 6. An apparatus for performing transmission power control by transmitting and receiving a transmission power control command, comprising means for measuring a CIR value of a received signal, wherein when the CIR value is equal to or more than a predetermined value, the transmission power is controlled. A transmission power control method characterized by ignoring a control command. 7. An apparatus for performing transmission power control by transmitting and receiving a transmission power control command, comprising means for measuring a CIR value of a received signal, wherein the CIR value is greater than or equal to a predetermined value. Is increased by a predetermined value.