JPH10112682A - Radio communication system and transmission power control method and base station therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radio communication system capable of simplifying the control procedure of transmission power, improving the throughput of communication and simplifying the constitution of hardwares required for the control of the transmission power. SOLUTION: In the transmission operation of a mobile terminal equipment, signals amplified by a fixed gain amplifier 222 are transmitted by one of antennas 201a and 201b selected by an antenna changeover switch 202 after unrequired signals are eliminated by a band-pass filter 203 through a transmission/reception changeover switch 204. After training signals are transmitted for fixed time, original data are transmitted and the transmission/reception of data are started. In the meantime, in the reception operation of a base station, in the case that the input level of a variable gain amplifier 108 is too high and exceeds a control range, that is in the case that the intensity of reception signals is too high, an AGC control part 109 controls the gain of the variable gain amplifier 105 and suppresses the input level of the variable gain amplifier 108 to a stipulated value.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a radio communication system for controlling transmission power between a base station and a terminal device.

[0002]

2. Description of the Related Art In recent years, wireless communication has been rapidly advanced and used in various fields. There is also a high demand for high-speed wireless communication, and a method of multiplexing baseband signals is being studied in order to achieve a higher transmission rate in a limited frequency band. An example of this is a technique of a code division multiplexing method. In this method, since data is multiplexed and transmitted in the amplitude direction, linearity is required for each unit.

On the other hand, a wide dynamic range is required to expand a communication area.

In order to satisfy both requirements, it is common practice to control the transmission power (suppress the transmission power when the communication distance is short).

Hereinafter, a transmission power control method in a conventional wireless communication system will be described. FIG. 4 is a block diagram showing a configuration of a radio unit of a conventional radio. In the figure, 301a and 301b are antennas, and 302 is an antenna switch.

Reference numerals 303, 318 and 321 denote band-pass filters (BPF) for removing unnecessary signals, reference numeral 304 denotes a transmission / reception switch, and reference numeral 305 denotes a low noise amplifier (LN).
A).

306 is a down mixer for frequency conversion, 307 is a low-pass filter (LPF) for removing unnecessary signals, 308 is a variable gain amplifier (AGC amplifier) for keeping the level of the received signal constant, 309 An AGC control unit having a function of passing control information of the variable gain amplifier (AGC amplifier) 308 to a higher-level control system.

Reference numeral 310 denotes a detector for detecting the intensity of the received signal, 311 denotes a demodulator, 312a and 312b denote filters for limiting the band of the received signal, and 313 denotes an A / D converter for converting an analog signal into a digital signal.

Reference numeral 314 denotes a baseband signal processing unit for performing processing such as multiplexing of baseband; 315, a D / A converter for converting a digital signal into an analog signal;
a, 316b are filters for limiting the band of the baseband signal, 317 is a modulator, 319 is a fixed gain amplifier, 3
Numeral 20 denotes an up-mixer for frequency conversion, and numeral 322 denotes a variable gain amplifier for varying a transmission output.

Reference numeral 323 denotes a frequency synthesizer for generating a carrier signal necessary for performing frequency conversion, modulation and demodulation,
Reference numeral 24 denotes a reference oscillator such as a temperature-compensated crystal oscillator (TCXO). Reference numeral 325 denotes a down-mixer 306 and an up-mixer 320 of the carrier signal generated by the frequency synthesizer 323.
Switch.

The operation of the radio unit having the above configuration will be described.

[Operation at Receiving] Antenna Switch 302
The training signal in the power control communication sequence received by the antenna 301a or the antenna 301b selected by
03, the signal in an unnecessary band is removed, and the signal is input to the low noise amplifier 305.

The received signal amplified by the low noise amplifier 305 is output from the down mixer 306 to a frequency synthesizer 323.
The frequency conversion (down-conversion) is performed by multiplying by the carrier signal generated in step (1).

The output of the down mixer 306 is input to a variable gain amplifier 308 after an image signal is removed by a low pass filter 307. Variable gain amplifier 308, AG
The C control unit 309 and the detector 310 constitute a feedback control circuit. The output of the variable gain amplifier 308 is measured by the detector 310, and the variable gain amplifier is controlled by the AGC control unit 309 so that the output level becomes constant. The gain of 308 is controlled.

If the input level of the variable gain amplifier 308 is too high and exceeds the control range, that is, if the strength of the received signal is too high, the AGC control unit 309 passes information (saturation signal) to that effect to the upper control system. . When a saturation signal is received from the AGC control unit 309, it notifies the transmitting side via a communication procedure in a power control communication sequence.

The above operation sequence is performed by the variable gain amplifier 30.
8 is repeated until it falls within the control range of 8. After the above-described operation sequence is completed, the signal having the normal level is demodulated by the demodulator 311, band-limited by the filters 312 a and 312 b, converted to digital data by the A / D converter 313, and converted to a baseband signal processing unit. 314.

[Operation at the time of transmission] Data passed by the baseband signal processing section 314 (a training signal at first for a power control communication sequence) is converted into analog data by a D / A converter 315 and then filtered. The band is limited at 316 a and 316 b, and is passed to the modulator 317.

The modulator 317 performs modulation based on the input data and the carrier signal generated by the frequency synthesizer 323. The modulated signal is passed through a bandpass filter 318.
Thus, the unnecessary signal is removed, and is passed to the fixed gain amplifier 319. The signal amplified to a predetermined level is multiplied by a carrier signal generated by a frequency synthesizer 323 in an up mixer 320 to perform frequency conversion (up-conversion).

The frequency-converted (up-converted) signal from the up-mixer 320 is converted to a band-pass filter 321.
Then, unnecessary signals such as image signals are removed and input to the variable gain amplifier 322.

The gain of the variable gain amplifier 322 is controlled by a higher-level control system via a baseband signal processing unit 314. The gain of the variable gain amplifier 322 is initially set to a constant value.

The signal amplified by the variable gain amplifier 322 is filtered by a bandpass filter 303 via a transmission / reception changeover switch 304 to remove unnecessary signals.
01a or 301b.

After transmission, the operation transits to the reception operation, receives control information from the reception side, and when the transmission power is too large, decreases the gain of the variable gain amplifier 322, transmits the training signal again, and transits to the reception operation.

[Power Control Sequence] The above power control sequence is repeated until a signal indicating a normal level is received from the receiving side. After receiving the signal indicating the normal level, the original data is transmitted, and transmission / reception of data is started.

[0024]

However, the conventional wireless communication system has the following problems.
That is, since it is necessary to control the transmission power on both the transmitting side and the receiving side, the control procedure is complicated, and the communication throughput (the amount of work per predetermined time that the system can perform) decreases. .

Also, it is necessary to have hardware (variable gain amplifier or a combination of fixed gain amplifier and variable attenuator) necessary for controlling the transmission power on both the transmitting side and the receiving side, and the hardware configuration becomes complicated. turn into.

Accordingly, an object of the present invention is to provide a wireless communication system capable of improving the communication throughput by simplifying the transmission power control procedure and simplifying the hardware configuration required for the transmission power control. I do.

[0027]

According to a first aspect of the present invention, there is provided a radio communication system for controlling transmission power between a base station and a terminal device. Comprises a transmitting means for transmitting the training signal for a predetermined time, and a fixed gain amplifying means for amplifying the transmitted training signal with a fixed gain,
The base station is a receiving unit that receives the training signal, a variable gain amplifying unit that inputs the received training signal, and amplifies an output level of the training signal with a variable gain, and the amplified output level is Gain control means for controlling the variable gain so as to be constant; and an input level of the training signal such that the training signal input to the variable gain amplification means falls within an input control range of the variable gain amplification means. Input level control means for controlling.

[0028] In the wireless communication system according to the second aspect, in the wireless communication system according to the first aspect, when the transmission power and the gain at the time of reception are the same in both the base station and the terminal device, the terminal device is connected to the base station. It is characterized in that information about transmission power is not notified.

According to a third aspect of the present invention, in the base station for performing wireless communication with a terminal device, receiving means for receiving a training signal transmitted from the terminal device, and inputting the received training signal Variable gain amplifying means for amplifying the output level of the training signal with a variable gain; gain control means for controlling the variable gain so that the amplified output level is constant; and input to the variable gain amplifying means. Input level control means for controlling an input level of the training signal so that the training signal falls within an input control range of the variable gain amplifying means.

According to a fourth aspect of the present invention, in the transmission power control method for a wireless communication system for performing wireless communication between a base station and a terminal device, the terminal device transmits a training signal for a predetermined time. The base station receives the training signal, inputs the received training signal, and varies the output level of the training signal by a variable gain amplifying unit. Amplify with gain,
When controlling the variable gain so that the amplified output level becomes constant, the training signal is input so that the training signal input to the variable gain amplifying means falls within the input control range of the variable gain amplifying means. Is characterized in that the input level is controlled.

According to a fifth aspect of the present invention, in the wireless communication system according to the first aspect, the wireless communication is a direct spread spectrum spread spectrum communication.

According to a sixth aspect of the present invention, in the wireless communication system according to the fifth aspect, the direct spread spectrum spread communication is a code division multiplex system.

According to a seventh aspect of the present invention, in the wireless communication system for controlling transmission power between a base station and a terminal device, one of the base station and the terminal device includes a transmitting unit for transmitting a training signal for a predetermined time. Fixed gain amplifying means for amplifying the transmitted training signal with a fixed gain, wherein the other of the base station and the terminal device receives the training signal, and receives the received training signal. Variable gain amplifying means for amplifying the output level of the training signal with a variable gain, gain control means for controlling the variable gain so that the amplified output level is constant, and input to the variable gain amplifying means. Input level of the training signal so that the training signal falls within the input control range of the variable gain amplifying means. Characterized by comprising an input level control means Gosuru.

[0034]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the radio communication system according to the present invention will be described. The wireless communication in the present embodiment is direct spread spectrum spread spectrum (DSSS) communication, and the direct spread spectrum spread communication is code division multiplexing (CDM).

[Base Station Side] FIG. 1 is a block diagram showing the configuration of the radio section on the base station side. In the figure, 101a, 10
1b is an antenna, and 102 is an antenna changeover switch. Reference numerals 103, 118, and 121 denote band-pass filters (BPFs) for removing unnecessary signals; 104, a transmission / reception switch; and 105, a variable gain amplifier.
Note that a combination of a fixed gain amplifier and a variable attenuator may be used instead of the variable gain amplifier 105.

106 is a down mixer for frequency conversion, 107 is a low-pass filter (LPF) for removing unnecessary signals, 108 is a variable gain amplifier (AGC amplifier) for keeping the level of the received signal constant, 109 Is a variable gain amplifier (AGC) for the upper control system (mobile terminal device).
An AGC control unit having a function of passing control information of the amplifier 108. The control information includes a signal indicating that the received signal has reached a normal level. In the present embodiment, this signal is not particularly notified to the mobile terminal device.

Reference numeral 110 denotes a detector for detecting the intensity of the received signal, 111 denotes a demodulator, 112a and 112b denote filters for limiting the band of the received signal, and 113 denotes an A / D converter for converting an analog signal into a digital signal.

Reference numeral 114 denotes a baseband signal processing unit for performing processing such as multiplexing of baseband; 115, a D / A converter for converting a digital signal into an analog signal;
a and 116b are filters for limiting the band of the baseband signal, 117 is a modulator, 119 is a fixed gain amplifier, 1
Reference numeral 20 denotes an up-mixer for frequency conversion, and reference numeral 122 denotes a variable gain amplifier that varies a transmission output.

Reference numeral 123 denotes a frequency synthesizer for generating a carrier signal necessary for performing frequency conversion, modulation and demodulation, and 1
Reference numeral 24 denotes a reference oscillator such as a temperature-compensated crystal oscillator (TCXO). Reference numeral 125 denotes a carrier signal generated by the frequency synthesizer 123 by a down mixer 106 and an up mixer 120.
Switch.

[Mobile Terminal] FIG. 2 is a block diagram showing the configuration of the radio section of the mobile terminal. 2 in the figure
01a and 201b are antennas, and 202 is an antenna changeover switch.

Reference numerals 203, 218 and 221 denote band-pass filters (BPF) for removing unnecessary signals, reference numeral 204 denotes a transmission / reception switch, and reference numeral 205 denotes a low noise amplifier (LN).
A).

Reference numeral 206 denotes a down mixer for frequency conversion, 207 denotes a low-pass filter (LPF) for removing unnecessary signals, 208 denotes a variable gain amplifier (AGC amplifier) for keeping the level of a received signal constant, and 209. An AGC control unit having a function of passing control information of the variable gain amplifier (AGC amplifier) 208 to a higher-level control system. The control information includes AGC amplifier 20 as information on transmission power.
8 contains information about the strength of the received signal that the input level is too high and exceeds the control range.

Reference numeral 210 denotes a detector for detecting the intensity of the received signal, 211 denotes a demodulator, 212a and 212b denote filters for limiting the band of the received signal, and 213 denotes an A / D converter for converting an analog signal into a digital signal.

Reference numeral 214 denotes a baseband signal processing unit for performing processing such as multiplexing of baseband; 215, a D / A converter for converting a digital signal into an analog signal;
a, 216b are filters for limiting the band of the baseband signal, 217 is a modulator, 219 is a fixed gain amplifier, 2
20 is an up-mixer for frequency conversion, and 222 is a fixed gain amplifier.

A frequency synthesizer 223 generates a carrier signal necessary for performing frequency conversion, modulation and demodulation.
Reference numeral 24 denotes a reference oscillator such as a temperature compensated crystal oscillator (TCXO). Reference numeral 225 denotes a carrier signal generated by the frequency synthesizer 223.
Switch.

The operation of the wireless communication system having the above configuration will be described.

[Reception Operation of Base Station] Antenna Switch 1
02, the training signal in the power control communication sequence received by the antenna 101a or the antenna 101b selected by the antenna 101a is a band-pass filter (BP
F) The signal is input to 103, the signal in an unnecessary band is removed, and input to the variable gain amplifier 105.

The received signal amplified by the variable gain amplifier 105, which is initially controlled to a fixed gain, is multiplied by the downmixer 106 with the carrier signal generated by the frequency synthesizer 123 to perform frequency conversion (downconversion). .

The output of the down mixer 106 is input to the variable gain amplifier 108 after the image signal is removed by the low pass filter 107. Variable gain amplifier 108, AG
The C control unit 109 and the detector 110 constitute a feedback control circuit. The output of the variable gain amplifier 108 is measured by the detector 110, and the AGC control unit 109 controls the variable gain amplifier so that the output level becomes a constant value. The gain of 108 is controlled.

When the input level of the variable gain amplifier 108 is too high and exceeds the control range, that is, when the strength of the received signal is too high, the AGC control unit 109 sets the variable gain amplifier 10
5, the input level of the variable gain amplifier 108 is suppressed to a specified value. The signal having the normal level by the above operation is demodulated by the demodulator 111 and then filtered by the filter 112.
a, 112b, A / D converter 113
Is converted into digital data, and is passed to the baseband signal processing unit 114.

[Transmission Operation of Base Station] The data passed by the baseband signal processing unit 114 (a training signal at first for a power control communication sequence) is converted into analog data by a D / A converter 115, The band of the modulator 11 is limited by the filters 116a and 116b.
Passed to 7.

The modulator 117 performs modulation based on the input data and the carrier signal generated by the frequency synthesizer 123. The modulated signal is passed to a bandpass filter 118
Thus, the unnecessary signal is removed, and is passed to the fixed gain amplifier 119. The signal amplified to a predetermined level is multiplied by the carrier signal generated by the frequency synthesizer 123 in the up mixer 120 to perform frequency conversion (up-conversion).

The frequency-converted (up-converted) signal from the up-mixer 120 is applied to a band-pass filter 121.
Then, unnecessary signals such as image signals are removed and input to the variable gain amplifier 122.

The gain of variable gain amplifier 122 is controlled by a higher-level control system (mobile terminal device) via baseband signal processing section 114. The gain of the variable gain amplifier 122 is initially set to a constant value.

After the unnecessary signal is removed from the signal amplified by the variable gain amplifier 122 through the transmission / reception changeover switch 104 by the bandpass filter 103, the antenna 1 selected by the antenna changeover switch 102 is removed.
01a or 101b.

After the transmission, the operation transits to the reception operation, receives control information from the reception side (mobile terminal device), and if the transmission power is too large, reduces the gain of the variable gain amplifier 122 and transmits the training signal again. Transition to receiving operation.

[Power Control Sequence] The above power control sequence is repeated until a signal indicating a normal level is received from the receiving side (mobile terminal device). After receiving the signal indicating the normal level, the original data is transmitted, and transmission / reception of data is started.

[Transmission operation of mobile terminal apparatus] The data passed by the baseband signal processing section 214 (a training signal at first for a power control communication sequence) is D /
After being converted into analog data by the A converter 215, the data is band-limited by the filters 216 a and 216 b and passed to the modulator 217.

The modulator 217 performs modulation based on the input data and the carrier signal generated by the frequency synthesizer 223. The modulated signal is passed through a bandpass filter 218.
Thus, the unnecessary signal is removed, and is passed to the fixed gain amplifier 219. The signal amplified to a predetermined level is multiplied by the carrier signal generated by the frequency synthesizer 223 in the up-mixer 220 to perform frequency conversion (up-conversion).

The frequency-converted (up-converted) signal from the up-mixer 220 is output to the band-pass filter 221.
Then, unnecessary signals such as image signals are removed and input to the fixed gain amplifier 222.

After the unnecessary signal is removed from the signal amplified by the fixed gain amplifier 222 by the band pass filter 203 via the transmission / reception switch 204, the antenna 2 selected by the antenna switch 202
01a and 201b.

After transmitting the training signal for a certain period of time,
The original data is transmitted, and data transmission / reception is started.

[Reception Operation of Mobile Terminal Device] The training signal in the power control communication sequence received by the antenna 201a or 201b selected by the antenna switch 202 is input to the band-pass filter (BPF) 203 and becomes unnecessary. The band signal is removed and input to the low noise amplifier 205.

The received signal amplified by the low noise amplifier 205 is output from the down mixer 206 to the frequency synthesizer 223.
The frequency conversion (down-conversion) is performed by multiplying by the carrier signal generated in step (1).

The output of the down mixer 206 is input to the variable gain amplifier 208 after the image signal is removed by the low pass filter 207. Variable gain amplifier 208, AG
The C control section 209 and the detector 210 constitute a feedback control circuit, and the output of the variable gain amplifier 208 is measured by the detector 210, and the AGC control section 209 controls the variable gain amplifier so that the output level becomes constant. The gain of 208 is controlled.

If the input level of the variable gain amplifier 208 is too high and exceeds the control range, that is, if the strength of the received signal is too high, the AGC control unit 209 informs the higher control system (base station) of the information (saturation). Pass). When a saturation signal is received from the AGC control unit 209, it notifies the transmitting side (base station) via a communication procedure in a power control communication sequence.

The above operation sequence is performed by the variable gain amplifier 20.
8 is repeated until it falls within the control range of 8. After the above operation sequence is completed, the signal having the normal level is demodulated by the demodulator 211, band-limited by the filters 212a and 212b, converted into digital data by the A / D converter 213, and processed by the baseband signal processing unit. Passed to 214.

In the above embodiment, when the input level of the variable gain amplifier 108 is too high on the base station side and exceeds the control range, the AGC control section 109 controls the variable gain amplifier 105
And the input level of the variable gain amplifier 108 is suppressed to a specified value so that the base station does not need to notify the mobile terminal device of the strength of the received signal. The terminal device may have this configuration, so that the mobile terminal device does not need to notify the base station of the strength of the received signal. Furthermore, since both the base station and the mobile terminal have the same configuration, it is not necessary to mutually notify the strength of the received signal.

In the above embodiment, the transmission power of the base station is controlled by measuring the transmission power from the base station by the mobile terminal device and notifying the measured power via the communication procedure from the mobile terminal device to the base station. . However, when the transmission power and the reception gain of both the mobile terminal device and the base station are equal, the transmission power from the mobile terminal device is measured at the base station side and set to the variable gain amplifier 105 (or attenuator) on the reception side. By converting the amount of attenuation from the value and setting the same amount of attenuation in the variable gain amplifier 122 (or attenuator) on the transmitting side as on the receiving side, the same control as in the above embodiment can be performed. 3 shows the configuration.

FIG. 3 is a block diagram showing the configuration of another radio section on the mobile terminal apparatus side. The same components as those in FIG. 2 are denoted by the same reference numerals, and description thereof will be omitted. In this case, since all control is performed by the base station, A
The GC control unit 409 can omit the function of notifying control data to a higher-level control system (base station).

Accordingly, it is not necessary to notify the transmission power from the base station via the communication procedure from the mobile terminal apparatus to the base station, so that the communication procedure can be simplified and the throughput can be further improved.

[0072]

According to the radio communication system according to the first aspect of the present invention, when controlling transmission power between a base station and a terminal device, the terminal device transmits a training signal by a transmission means for a predetermined time, The training signal transmitted by the fixed gain amplifying means is amplified by a fixed gain, and the base station receives the training signal by a receiving means, and inputs the received training signal by a variable gain amplifying means, and The output level of the signal is amplified with a variable gain, the variable gain is controlled by a gain control means so that the amplified output level becomes constant, and the training is input to the variable gain amplification means by an input level control means. Since the input level of the training signal is controlled so that the signal falls within the input control range of the variable gain amplifying means, Requires the base station without notifying the information (received signal strength) related to the transmission power to the terminal apparatus, it may be the one-way notifications from the terminal apparatus to the base station and improve the communication throughput.

Since the terminal device does not need to control the transmission power, the hardware configuration required for communication can be simplified. Therefore, components such as a relatively expensive variable gain amplifier can be reduced, and the cost can be reduced.

Further, since a plurality of terminal devices are generally provided for one base station, the greater the system configuration (the number of terminal devices accommodated in one base station), the greater the cost reduction effect.

According to the second aspect of the present invention, when the transmission power and the gain at the time of reception are the same in both the base station and the terminal device, the terminal device does not notify the base station of information on the transmission power. Therefore, by making the reception level and the transmission level the same, both the base station and the terminal device can omit the notification of the information (reception signal strength) regarding the transmission power. Therefore, the communication procedure can be simplified, and the communication throughput can be further improved. Also,
Since the base station does not need to control the transmission power, the hardware configuration required for communication can be further simplified.

According to the third aspect of the present invention, when wireless communication is performed with the terminal device, the training signal transmitted from the terminal device is received by the receiving means, and the received training signal is received by the variable gain amplifying means. The training signal is input, the output level of the training signal is amplified with a variable gain, the variable gain is controlled by a gain control means so that the amplified output level is constant, and the variable level is controlled by an input level control means. Since the input level of the training signal is controlled so that the training signal input to the gain amplifying means falls within the input control range of the variable gain amplifying means, information on transmission power (reception signal strength) is transmitted from the base station to the terminal device. ) Need not be notified, and a one-way notification from the terminal device to the base station is sufficient, and the communication throughput can be improved.

According to the transmission power control method for a wireless communication system according to claim 4, in the transmission power control method for a wireless communication system for performing wireless communication between a base station and a terminal device, the terminal device transmits a training signal to a predetermined position. The base station receives the training signal, inputs the received training signal, and outputs the training signal by a variable gain amplifying means. When the variable gain is controlled so that the amplified output level is constant, the training signal input to the variable gain amplifying unit is within an input control range of the variable gain amplifying unit. Since the input level of the training signal is controlled to be within the Finished No. strength) without notification to,
One-way notification from the terminal device to the base station is sufficient, and communication throughput can be improved.

According to the fifth aspect of the present invention, since the wireless communication is a direct spread spectrum spread communication, it can be applied to a direct spread wireless communication.

According to the radio communication system of the present invention, since the direct spread spectrum spread communication is a code division multiplex system, it can be applied to a code division multiplex system radio communication.

According to the radio communication system of the present invention, when controlling the transmission power between the base station and the terminal device,
One of the base station and the terminal device transmits a training signal by a transmission unit for a predetermined time, amplifies the transmitted training signal by a fixed gain amplifying unit with a fixed gain, and the other of the base station and the terminal unit receives a training signal. Means for receiving the training signal, inputting the received training signal, amplifying the output level of the training signal with variable gain by variable gain amplifying means, and keeping the amplified output level constant by gain control means. And the input level of the training signal is controlled by the input level control means such that the training signal input to the variable gain amplifying means falls within the input control range of the variable gain amplifying means. Information on the transmission power (the received signal strength) from one of the base station and the terminal device to the other. ) Do not have to notify, it may be the one-way notifications from the one to the other, it is possible to improve the communication throughput.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a radio unit on a base station side.

FIG. 2 is a block diagram illustrating a configuration of a wireless unit on the mobile terminal device side.

FIG. 3 is a block diagram illustrating a configuration of another wireless unit on the mobile terminal device side.

FIG. 4 is a block diagram illustrating a configuration of a wireless unit of a conventional wireless device.

[Explanation of symbols]

 105, 108, 122 Variable gain amplifier 109, 409 AGC control unit 205, 405 Low noise amplifier 222, 422 Fixed gain amplifier 114, 214, 412 Baseband signal processing unit

Claims (7)

[Claims] 1. A wireless communication system for controlling transmission power between a base station and a terminal device, wherein the terminal device transmits a training signal for a predetermined time, and amplifies the transmitted training signal with a fixed gain. A fixed gain amplifying means, wherein the base station receives the training signal, a variable gain amplifying means for receiving the training signal, and amplifying an output level of the training signal with a variable gain. Gain control means for controlling the variable gain so that the amplified output level is constant; and the training signal input to the variable gain amplifying means falls within an input control range of the variable gain amplifying means. Wireless communication system further comprising input level control means for controlling an input level of the training signal. . 2. The transmission apparatus according to claim 1, wherein when the transmission power and the gain at the time of reception are the same in both the base station and the terminal apparatus, the terminal apparatus does not notify the base station of information regarding the transmission power. Wireless communication system. 3. A base station for performing wireless communication with a terminal device, a receiving means for receiving a training signal transmitted from the terminal device, an input of the received training signal, and an output of the training signal. Variable gain amplifying means for amplifying a level with a variable gain; gain control means for controlling the variable gain so that the amplified output level is constant; and wherein the training signal input to the variable gain amplifying means is A base station comprising: input level control means for controlling an input level of the training signal so as to fall within an input control range of the variable gain amplifying means. 4. A transmission power control method for a wireless communication system for performing wireless communication between a base station and a terminal device, wherein the terminal device transmits a training signal for a predetermined time, and amplifies the transmitted training signal with a fixed gain. The base station receives the training signal, inputs the received training signal, amplifies the output level of the training signal with variable gain by variable gain amplifying means, and the amplified output level is constant. When controlling the variable gain such that the input level of the training signal is controlled so that the training signal input to the variable gain amplifying means falls within the input control range of the variable gain amplifying means. A transmission power control method for a wireless communication system. 5. The wireless communication system according to claim 1, wherein said wireless communication is a direct spread spectrum spread spectrum communication. 6. The spread spectrum communication of the direct spread system is a code division multiplex system.
A wireless communication system as described. 7. A wireless communication system for controlling transmission power between a base station and a terminal device, wherein one of the base station and the terminal device transmits a training signal for a predetermined time, A fixed gain amplifying means for amplifying with a fixed gain, the other of the base station and the terminal device receiving means for receiving the training signal, inputting the received training signal, and adjusting an output level of the training signal. Variable gain amplifying means for amplifying with a variable gain; gain controlling means for controlling the variable gain so that the amplified output level is constant; and the training signal input to the variable gain amplifying means is a variable gain amplifying means. Input level control means for controlling the input level of the training signal so as to fall within the input control range of the amplification means; Wireless communication system characterized by comprising.