JP2003188816A - Mobile wireless terminal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mobile wireless terminal that can prevent erroneous transmission power control so as to avoid disturbance on other communication, waste of power, and maintain the communication. <P>SOLUTION: A control interval calculation section 140 monitors a CRC (Cyclic Redundancy Check) bit extracted from data received by a CRC bit extract section 130, and controls a transmission power control section 150 to control transmission power by each slot when a state of not causing any error in a received slot is consecutive. On the other hand, when errors are consecutive in the received slot, the control interval calculation section 140 controls the transmission power control section 150 to control the transmission power on the basis of the majority decision of TPC (Transmit Power Control) bits acquired by each slot only once as to a plurality of slots. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wireless communication system for performing closed loop transmission power control, such as CDM.
The present invention relates to a mobile radio terminal device used in an A-system mobile radio communication system.

[0002]

2. Description of the Related Art As is well known, in a mobile radio communication system for performing closed loop transmission power control, the transmission power of a mobile station is controlled as follows. That is, the base station RAKE-combines a plurality of signals received from the mobile station through a plurality of routes for each corresponding slot, and measures the SIR from the combined signals.

Then, the base station controls the transmission power so that the measured SIR becomes equal to the target SIR value, that is, TPC (Transmit power C).
ontrol) bit is generated, inserted into transmission data, and transmitted to the mobile station. The TPC bit is 1-bit data, and instructs the mobile station to increase or decrease the transmission power.

On the other hand, the mobile station extracts the TPC bit from the signal received from the base station. The position where the TPC bit is inserted is known to the mobile station in advance.

When the TPC bit instructs the mobile station to increase the transmission power, the mobile station increases the transmission power by 1 dB for transmission. On the other hand, when it instructs the transmission power to decrease, the transmission power is decreased by 1 dB. To send.

By controlling the transmission power of the mobile station in this way, the mobile station transmits with necessary and sufficient power, so that the mobile station can suppress the power consumption to a required level, and It is possible to minimize the interference with the communication.

By the way, if the reception quality is good in the mobile station, the bit error occurrence rate of the TPC bit is low. Therefore, the mobile station can perform optimum transmission power control by performing transmission power control according to the TPC bit. it can.

However, if the reception quality of the mobile station deteriorates, a bit error of the TPC bit is likely to occur. As a result, the TPC bit is 1-bit data. Therefore, if an error occurs in the TPC bit, the reverse transmission is performed. Power control will be performed.

By performing the reverse transmission power control in this way, for example, if the transmission power is increased more than necessary, not only the problem that the communication of other mobile stations in the same cell is disturbed occurs, The mobile station also has a problem of wasting power.

Further, if the transmission power is mistakenly reduced too much, the communication quality further deteriorates, and the transmission power control can no longer be performed, so that it is no longer possible to maintain the communication quality for the transmission power control. Will be disconnected.

[0011]

In the conventional mobile radio terminal device, when the TPC bit is erroneously detected, erroneous transmission power control is performed, which interferes with other communication, wastes power, or causes communication. There was a problem that was cut off.

The present invention has been made to solve the above-mentioned problems, and it is possible to prevent erroneous transmission power control, obstruct other communication, waste power, and maintain communication. An object is to provide a terminal device.

[0013]

In order to achieve the above-mentioned object, the present invention is used in a mobile communication system for performing wireless communication by a CDMA system, and the transmission power is controlled by an instruction through control information sent from a base station. In the mobile radio terminal device to be controlled, when the reception quality detecting means for detecting the reception quality and the reception quality detected by the reception quality detecting means are better than a preset level, the control cycle is determined to be the first cycle. On the other hand, if it is not good, set the control cycle to the first
Control cycle determining means for determining a second cycle longer than the cycle, control information detecting means for detecting control information, and control information detected by the control information detecting means within the control cycle determined by the control cycle determining means. Accordingly, the transmission power control means for controlling the transmission power is provided.

In the mobile radio terminal apparatus having the above configuration, if the reception quality is better than the preset level, the control cycle is determined to be the first cycle, while if it is not good, the control cycle is set to the first cycle. The second cycle, which is longer than the cycle, is determined, and the transmission power is controlled according to the control information detected by the control information detecting means within the control cycle.

Therefore, according to the mobile radio terminal apparatus having the above configuration, when the reception quality is not good, the transmission power is controlled based on a large amount of control information as compared with the case where the reception quality is good, which is erroneous. It is possible to prevent transmission power control, interfere with other communication, waste power, and maintain communication.

[0016]

DETAILED DESCRIPTION OF THE INVENTION An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows the configuration of a mobile radio terminal apparatus according to an embodiment of the present invention, and here, only the configuration particularly relating to transmission power control is shown.

The receiving system is a low noise amplifier (LN_AM
P) 20, frequency converter 30, quadrature demodulator 40, A / D
Converter (A / D) 50, SIR (SIR) calculator 60,
Searcher 70, finger 80, RAKE combiner (RAK
E) 90, data demodulator 100, channel decoder 11
Equipped with 0.

The radio signal transmitted from the base station is received by the antenna 10 and input to the low noise amplifier 20 where it is amplified.

The amplified received signal is transferred to the frequency conversion unit 30.
After being converted from the 2 GHz band to the intermediate frequency, the signal is amplified by the AGC. Then, the received signal of the intermediate frequency is subjected to quadrature detection in the quadrature demodulation unit 40 and divided into an in-phase component and a quadrature component.

The in-phase component and the quadrature component are A / D
The conversion unit 50 converts the analog signal into a digital signal and outputs it to the SIR calculation unit 60, the searcher 70, and the finger 80.

The SIR calculator 60 calculates SIR (signal power to interference power ratio) based on the digital signal provided from the A / D converter 50, and based on the calculation result, the transmission power on the base station side. Generate a TPC bit that controls The TPC bit generated here is transmitted to the base station through a transmission system described later.

The searcher 70 despreads the digital signal supplied from the A / D converter 50 using various spreading codes generated at various timings, detects a plurality of paths suitable for reception, and The finger 80 is provided with information for receiving the path.

The finger 80 despreads the digital signal supplied from the A / D converter 50 based on the information supplied from the searcher 70, and receives the path detected by the searcher 70.

The RAKE combiner 90 RAKE combines the paths received by the fingers 80 and outputs the combined result to the data demodulator 100. This combined result is demodulated by the data demodulation unit 100 and then decoded by the channel decoding unit 110 to reproduce the reception data of the channel addressed to itself, and the TPC bit extraction unit 120 and the CRC bit extraction unit 1
Is output to 30.

TPC bit extraction section 120 extracts TPC bits from the reproduced received data and outputs them to transmission power control section 150. The CRC bit extraction unit 130 uses a CRC (Cyclic Redundancy Check) based on the received data that has been reproduced.
k) Bits are extracted and output to the control interval calculation unit 140.

The control interval calculation unit 140 monitors the CRC bit and the occurrence status of the received data error, and determines the control interval n based on the monitoring result and the preset parameters C and E.

The transmission power control section 150 is based on the TPC bits extracted by the TPC bit extraction section 120 and the control interval n determined by the control interval calculation section 140, and a transmission amplifier (Tx_AMP) 260 described later. Control the gain of.

On the other hand, the transmission system includes a channel coding unit 20.
0, data modulator 210, spreader 220, D / A converter (D / A) 230, quadrature modulator 240, frequency converter 2
50 and a transmission amplifier 260.

The channel coding unit 200 inserts the TPC bit generated by the SIR calculation unit 60 into the transmission data, adds a CRC bit for detecting a block error for each transport block, and performs channel coding. To do.

The data modulator 210 data-modulates the channel coding result and outputs the modulation result to the spreader 220. The spreading unit 220 spreads the modulation result using a spreading code. This diffusion result is the D / A conversion unit 23.
At 0, it is converted into an analog signal.

Then, the analog signal is quadrature-modulated by the quadrature modulator 240, converted into an intermediate frequency, frequency-converted into a radio frequency in the 2 GHz band by the frequency converter 250, and output to the transmission amplifier 260. . Transmission amplifier 26
0 is an amplifier whose gain is variable, and its gain is controlled by the transmission power control unit 150 described above.

Next, the operation of the mobile radio terminal apparatus having the above configuration will be described. In the following description, the operation related to the transmission power control will be described, and a normal audio reproduction output process based on received data, a transmission data generation process based on input voice, a communication control with a base station, etc. The description of the operation is omitted.

First, the process of determining the transmission power control interval will be described. FIG. 2 is a flowchart for explaining the processing, which is performed by the control interval calculation unit 140 and is repeatedly performed for each slot. First, in step 2a, the CRC bit is acquired from the CRC bit extraction unit 130, and the process proceeds to step 2b.

In step 2b, the CRC bit obtained in step 2a is verified to determine whether an error has occurred. If an error has occurred, the process proceeds to step 2g. On the other hand, if no error has occurred, the process proceeds to step 2c.

In step 2c, the value of the parameter C is incremented by "1", the value of the parameter E is reset to "0", and the process proceeds to step 2d.

In step 2d, it is determined whether or not an error-free slot is continuously received Cth times or more, that is, whether the parameter C is Cth or more. If the parameter C is greater than or equal to Cth, the process proceeds to step 2e. On the other hand, if the parameter C is less than Cth, the process ends.

At step 2e, whether or not the current control interval is every slot, that is, the parameter N is "1".
Or not. Here, if the parameter N is "1", the process is ended, while if the parameter N is not "1", the process proceeds to step 2f.

In step 2f, the transmission power controller 150
To the control interval N to finish the process. As a result, the transmission power control unit 150 controls the transmission power for each slot as the control interval.

On the other hand, in step 2g, the value of the parameter C is reset to "0", the value of the parameter E is incremented by "1", and the process proceeds to step 2h.

In step 2h, it is determined whether or not a slot in which an error has occurred consecutively more than Eth times has been received, that is, whether the parameter E is more than Eth. If the parameter E is equal to or greater than Eth, the process proceeds to step 2i, while if the parameter E is less than Eth, the process ends.

In step 2i, the current control interval is n
(> 1) Whether or not it is for each slot, that is, whether or not the parameter N is "n" is determined. Here, if the parameter N is “n”, the process is ended, while if the parameter N is not “n”, step 2
j.

In step 2j, the transmission power controller 150
The control interval N is set to “n”, and the process ends. As a result, the transmission power control unit 150 controls the transmission power every n slots as the control interval.

Next, the processing for controlling the transmission power will be described. FIG. 3 is a flowchart for explaining the processing, which is performed by the transmission power control unit 150 and is executed when the power is turned on. First, in step 3a, the value of the parameter N is set to the initial value "1", the value of the parameter K is set to "0", and the process proceeds to step 3b.

In step 3b, it is determined whether or not an instruction to turn off the power has been received from the user through a user interface (not shown). Here, turn the power on
If the instruction to turn to FF is accepted, the process ends, while if the instruction to turn off the power is not accepted, the process proceeds to step 3c.

In step 3c, the TPC bit extraction unit 1
A new TPC bit is acquired from 20, and an instruction to increase the transmission power, that is, "1" and an instruction to decrease the transmission power, that is, "0" are respectively counted, and the process proceeds to step 3d. In step 3d, the value of the parameter K is incremented by "1", and the process proceeds to step 3e.

In step 3e, it is determined whether or not the value of the parameter K matches the value of the parameter N. The value of the parameter N is set by the control interval calculation unit 140 at any time.

If the parameter K matches the parameter N, the process proceeds to step 3f. On the other hand, if the parameter K does not match the parameter N, the process proceeds to step 3b.

At step 3f, the transmission power of the transmission amplifier 260 is controlled on the basis of the result counted at step 3c, and the process proceeds to step 3g. That is, when the instruction to increase the transmission power, that is, the count value of "1" is larger than the instruction to decrease the transmission power, that is, the count value of "0", the gain is increased by a predetermined level.

On the other hand, when the count value of "0" is larger than the count value of "1", the gain is reduced by a predetermined level. If the count value of "0" is equal to the count value of "1", the gain is increased or decreased by a predetermined level according to the instruction corresponding to the TPC bit counted last in step 3c.

At step 3g, the count result of the TPC bit is reset, the value of the parameter K is reset to "0", and the routine proceeds to step 3b.

Next, a specific example of the transmission power control in step 3f will be described with reference to FIG. In the example shown in this figure, the control interval calculation unit 140 uses the transmission power control unit 1
It is assumed that the instruction is given to 50 to set the control interval N to "6".

In the section T1, the TPC bit is "0100".
It is 10 ". The transmission power control unit 150
Counting is performed in the loop processing of steps 3b, 3c, 3d, and 3e, and as a result, it is requested that the instruction to increase the transmission power is “2” and the instruction to decrease the transmission power is “4”, and the instruction to decrease is more. Therefore, in the control of step 3f, the transmission power of the transmission amplifier 260 is controlled so as to reduce the gain by a predetermined level.

Similarly, in the next section T2, the TPC bit is "110111". Therefore, as a result of counting the TPC bits, the transmission power control unit 150 has an instruction to increase the transmission power as “5” and an instruction to decrease the transmission power as “1”, and since there are more instructions to increase the transmission power, the control in step 3f is performed. Then, the transmission power of the transmission amplifier 260 is controlled to increase the gain by a predetermined level.

Then, in the next section T3, the TPC bit is "101001". Therefore, as a result of counting the TPC bits, the transmission power control unit 150 indicates that the instruction to increase the transmission power and the instruction to decrease the transmission power are both "3", and the last instruction is the instruction to increase "1".
In the control of f, the transmission power of the transmission amplifier 260 is controlled so as to increase the gain by a predetermined level.

As described above, the mobile radio terminal apparatus having the above-mentioned configuration monitors the CRC bit and controls the transmission power for each slot when the received slots continue to be error-free. On the other hand, if there are consecutive errors in the received slots, 1 for multiple slots
Only once, the transmission power is controlled based on the majority vote of the TPC bits acquired in each slot.

Therefore, according to the mobile radio terminal apparatus having the above configuration, the transmission power is controlled on the basis of the TPC bits detected in a plurality of slots when the reception quality is deteriorated. Can be prevented, interference of other communication, waste of power, and maintenance of communication can be performed. When the reception quality is good, the transmission power can be controlled as usual.

The present invention is not limited to the above embodiment. In the above-described embodiment, the transmission power control is performed based on the reception quality based on the CRC bit, but instead of this, for example, with the configuration as shown in FIG. Even if the control interval N is controlled to control the transmission power according to the reception quality based on, the same effect can be obtained. Other,
It goes without saying that various modifications can be made without departing from the gist of the present invention.

[0058]

As described above, according to the present invention, when the reception quality is better than the preset level, the control cycle is determined to be the first cycle, and when it is not good, the control cycle is set. The second cycle, which is longer than the first cycle, is determined, and the transmission power is controlled according to the control information detected by the control information detecting means within the control cycle.

Therefore, according to the present invention, when the reception quality is not good, the transmission power is controlled based on a large amount of control information as compared with the case where the reception quality is good, so that erroneous transmission power control is prevented. As a result, it is possible to provide a mobile radio terminal device capable of interfering with other communication, wasting power, and maintaining communication.

[Brief description of drawings]

FIG. 1 is a circuit block diagram showing a configuration of an embodiment of a mobile radio terminal device according to the present invention.

2 is a flowchart for explaining a process of determining a control interval by a control interval calculating unit of the mobile wireless terminal device shown in FIG.

3 is a flowchart for explaining a process of controlling transmission power by a transmission power control unit of the mobile radio terminal device shown in FIG.

FIG. 4 is a diagram for explaining transmission power control of the mobile radio terminal device shown in FIG.

FIG. 5 is a circuit block diagram showing the configuration of another embodiment of the mobile radio terminal device according to the present invention.

[Explanation of symbols]

10 ... Antenna 20 ... Low noise amplifier (LN_AMP) 30 ... Frequency converter 40 ... Quadrature demodulator 50 ... A / D converter (A / D) 60 ... SIR calculation unit (SIR) 70 ... Searcher 80 ... fingers 90 ... RAKE synthesizer (RAKE) 100 ... Data demodulation unit 110 ... Channel decoding unit 120 ... TPC bit extraction unit 130 ... CRC bit extraction unit 140 ... Control interval calculation unit 150 ... Transmission power control unit 200 ... Channel coding unit 210 ... Data modulator 220 ... diffusion part 230 ... D / A converter (D / A) 240 ... Quadrature modulator 250 ... Frequency converter 260 ... Transmission amplifier

Claims (6)

[Claims] 1. A CDMA (Code Division Multiple Acc)
In a mobile wireless terminal device that is used in a mobile communication system that performs wireless communication according to the (ess) method and that controls transmission power according to an instruction through control information sent from a base station, reception quality detection means that detects reception quality, and If the reception quality detected by the quality detecting means is better than a preset level, the control cycle is determined to be the first cycle. On the other hand, if it is not good, the control cycle is set to be longer than the first cycle. In accordance with control information detected by the control information detection means within the control cycle determined by the control cycle determination means, the control cycle determination means for determining the second long cycle, the control information detection means for detecting the control information, And a transmission power control means for controlling the transmission power. 2. A CDMA (Code Division Multiple Acc)
In a mobile wireless terminal device that is used in a mobile communication system that performs wireless communication according to the (ess) method and that controls transmission power according to an instruction through control information sent from a base station, reception quality detection means that detects reception quality, and If the reception quality detected by the quality detecting means is better than a preset level, the control cycle is determined to be the first cycle. On the other hand, if it is not good, the control cycle is set to be longer than the first cycle. Control cycle determining means for determining a long second cycle; control information detecting means for detecting the control information; and control information detected by the control information detecting means within the control cycle determined by the control cycle determining means. A mobile radio terminal device, comprising: a transmission power control means for controlling transmission power according to an instruction having a larger instruction content. 3. The transmission power control means, when the control information detected by the control information detection means within the control cycle determined by the control cycle determination means has the same number of instructions to reduce the transmission power and the instruction to increase the transmission power. The mobile radio terminal device according to claim 2, wherein the mobile radio terminal device controls the transmission power according to an instruction of the control information acquired at a predetermined timing. 4. The control information acquired at the predetermined timing is the control information detected by the control information detecting means at the end of the control cycle determined by the control cycle determining means. 3. The mobile wireless terminal device according to item 3. 5. The reception quality detecting means includes a CRC (Cyclic Redundanc) sent from a base station together with the control information.
The mobile radio terminal device according to any one of claims 1 to 4, wherein the reception quality is detected based on (y Check) bits. 6. The mobile radio terminal device according to claim 1, wherein the reception quality detecting means detects a signal power to interference power ratio as a reception quality.