JP2009246434A - Base station apparatus and control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide the base station apparatus capable of performing suitable gain control even for rapid amplitude variation in an uplink signal, and converging the output amplitude of an AGC amplifier at a constant level quickly. <P>SOLUTION: The base station apparatus 1 comprises a signal amplifying portion 121, a desired wave electric power value computation portion 181, an assumed disturbance wave electric power value computation portion 182, and a gain control portion 153. The desired wave electric power value computation portion 181 computes an electric power value of a desired wave contained in a second signal transmitted by a mobile station 2 with a transmission timing after transmission of a first signal based on a scheduling information. The assumed disturbance wave electric power value computation portion 182 computes an electric power value of an assumed disturbance wave contained in the second signal based on the received quality of the first signal. The gain control portion 153 controls the gain of the signal amplifying portion 121 beforehand so that the amplitude of the second signal outputted from the signal amplifying portion 121 becomes a constant value, based on the electric power value of the desired wave and the electric power value of the assumed disturbance wave. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a base station apparatus and a control method.

  Generally, in a base station of a wireless mobile communication system, an AGC (Automatic Gain Control) amplifier is used in order to keep a received signal within a predetermined dynamic range. The received signal is amplified by the AGC amplifier, and the output is given to the AGC amplifier control unit. The AGC amplifier control unit controls the gain of the AGC amplifier so that the output amplitude of the AGC amplifier is constant regardless of the amplitude of the input signal.

  As this kind of technology, Patent Document 1 predicts a received power value of a transmission unit at the next control timing from a TPC (Transmit Power Control) command to the mobile station and the received power value of the previous transmission unit. The technology to do is described.

Patent Document 2 uses the power measurement result of the current reception time slot, the power of the code signal disappearing from the next reception time slot, and the power of the code signal newly added to the next reception time slot. A technique for calculating the power value of the next reception time slot and using it for gain control of the AGC amplifier is described.
Japanese Patent Application Laid-Open No. 2002-076996 JP 2006-523413 A

  In mobile communication systems, the frequency of occurrence of traffic bursts is high. When a burst-like received signal that rises sharply on the uplink is generated and received by the base station apparatus, appropriate AGC amplifier gain control cannot be performed quickly, so that the rising part of the signal falls within a predetermined dynamic range. The received data cannot be demodulated and may be lost.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to perform appropriate gain control even for a sudden amplitude fluctuation of an uplink signal, and to make the output amplitude of the AGC amplifier constant more quickly. An object of the present invention is to provide a base station apparatus that can converge.

  According to the present invention, a receiving unit that receives a first signal transmitted by a mobile station, a signal amplifying unit that amplifies the first signal received by the receiving unit, and the first signal output by the signal amplifying unit A reception quality measuring unit that measures reception quality from the uplink, an uplink scheduling unit that generates uplink scheduling information based on the reception quality, and scheduling information that adds the scheduling information to a transmission signal transmitted to the mobile station In a base station apparatus of a wireless mobile communication system, comprising: an adding unit; and a transmitting unit that transmits a signal to which the scheduling information is added to the mobile station, based on the scheduling information, A desired wave power value calculation unit for calculating a power value of a desired wave included in a second signal transmitted by the mobile station at a transmission timing; The assumed interference wave power value calculation unit for calculating the power value of the assumed interference wave included in the second signal based on the reception quality of the signal, and the amplitude of the second signal output from the signal amplification unit is constant A base station apparatus comprising: a gain control unit that controls a gain of the signal amplification unit based on a power value of the desired wave and a power value of the assumed interference wave Provided.

  According to the present invention, there is also provided a control method for a base station apparatus of a wireless mobile communication system, the step of receiving a first signal transmitted by a mobile station, the step of amplifying the received first signal, and amplification Measuring reception quality from the first signal, generating uplink scheduling information based on the reception quality, and adding the scheduling information to a transmission signal transmitted to the mobile station; A step of transmitting a signal to which the scheduling information is added to the mobile station, and a hope included in the second signal transmitted by the mobile station at a transmission timing after transmission of the first signal based on the scheduling information Calculating a power value of a wave, calculating a power value of an assumed interference wave included in the second signal based on the reception quality of the first signal, and amplifying Pre-controlling the amplification gain of the second signal in consideration of the power value of the desired wave and the power value of the assumed interference wave so that the amplitude of the second signal is constant; There is provided a control method characterized by comprising:

  The various components of the present invention do not necessarily have to be independent of each other. A plurality of components are formed as a single member, and a single component is formed of a plurality of members. It may be that a certain component is a part of another configuration, a part of a certain component overlaps a part of another component, and the like.

  Moreover, although the some process is described in order in the control method of this invention, the order of the description does not limit the order which performs a some process. For this reason, when implementing the control method of this invention, the order of the some process can be changed in the range which does not interfere in content.

  According to the present invention, before receiving the uplink signal, the power value of the desired wave and the assumed jamming wave included in the uplink signal is calculated, and the gain of the AGC amplifier is controlled in advance based on the calculation result. There is provided a base station apparatus that can converge the output amplitude of the AGC amplifier quickly and uniformly to a burst-like received signal that rises sharply.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same reference numerals are given to the same components, and the description will be omitted as appropriate.

  FIG. 1 is a functional block diagram showing an embodiment of the base station apparatus of the present invention. The base station apparatus 1 includes a receiving unit 11 that receives a first signal transmitted from the mobile station 2, a signal amplifying unit 121 that amplifies the first signal received by the receiving unit 11, and a first signal output from the signal amplifying unit 121. A reception quality measurement unit 152 that measures reception quality from the signal, an uplink scheduling unit 16 that generates uplink scheduling information based on the reception quality, and scheduling information that adds scheduling information to a transmission signal transmitted to the mobile station 2 An adding unit 17 and a transmitting unit (not shown) that transmits a signal with scheduling information to the mobile station 2 are provided.

  Further, as a characteristic function of the present invention, the base station apparatus 1 uses the scheduling information to determine the power value of the desired wave included in the second signal transmitted by the mobile station 2 at a transmission timing after the transmission of the first signal. Desired wave power value calculating unit 181, an assumed jamming wave power value calculating unit 182 that calculates the power value of the assumed jamming wave included in the second signal based on the reception quality of the first signal, and the signal amplifying unit 121. A gain control unit 153 that controls the gain of the signal amplification unit 121 in advance in consideration of the power value of the desired wave and the power value of the assumed interference wave so that the amplitude of the second signal output from I have.

  In addition, the base station apparatus 1 according to the present embodiment includes an RF circuit unit 12, an A / D converter unit 13, an I / Q orthogonal demodulation unit 14, a baseband circuit unit 15, and an assumed received power value calculation unit 18. , The D / A converter unit 19, the RF circuit unit 12 includes a signal amplification unit 121, the baseband circuit unit 15 includes a demodulation / combination unit 151, a reception quality measurement unit 152, and a gain control unit 153. The assumed received power value calculation unit 18 may include a desired wave power value calculation unit 181 and an assumed interference wave power value calculation unit 182.

  The uplink signal transmitted from the mobile station 2 to the base station apparatus 1 is received by the receiving unit 11. This signal is transmitted to the RF circuit unit 12 and amplified by the signal amplification unit 121 so as to be within a predetermined dynamic range. In addition to the signal amplifier 121, the RF circuit unit 12 may include members generally required for the configuration of the RF circuit, such as a band pass filter and a frequency converter.

  The signal output from the RF circuit unit 12 is converted into a digital signal by the A / D converter unit 13, subjected to I / Q orthogonal demodulation by the I / Q orthogonal demodulation unit 14, and input to the baseband circuit unit 15. .

  The signal input to the baseband circuit unit 15 is demodulated and combined by the demodulation / combination unit 151 and transmitted to the mobile communication control device. The reception quality measuring unit 152 measures the reception quality of the reception signal from each mobile station 2 from the information obtained at the time of demodulation and combination. The reception quality measured here includes CQI (Channel Quality Indicator), SIR (Signal to Interference Ratio), and the like. The gain control unit 153 included in the baseband circuit unit 15 will be described later.

  In an LTE (Long Term Evolution) base station apparatus, uplink radio resources are used so that radio resources can be efficiently used as a whole from the CQI, SIR, etc. of each mobile station obtained when demodulating / combining received signals. Is assigned to each mobile station. This is called uplink scheduling. In the present embodiment, the uplink scheduling unit 16 performs uplink scheduling based on the reception quality measured by the reception quality measurement unit 152, and generates uplink scheduling information. The scheduling information adding unit 17 transmits the uplink scheduling information to the transmission system circuit in order to add the uplink scheduling information to the downlink signal transmitted to the mobile station 2. The transmitted uplink scheduling information is added to the downlink signal generated by the transmission system circuit, and is transmitted to the mobile station 2 from a transmission unit (not shown).

  The uplink signal received by the base station apparatus of the mobile communication system includes a desired wave necessary for communication and an unnecessary interference wave. A communication error occurs when the ratio between the desired wave and the jamming wave exceeds a certain value, and therefore, system design or system control is generally performed so that the ratio between the desired wave and the jamming wave becomes small.

  The desired wave power value calculation unit 181 calculates the power value of the desired wave included in the uplink signal to be received in the future based on the uplink scheduling information generated by the uplink scheduling unit 16. If the uplink signal is transmitted from the mobile station 2 according to the uplink scheduling information, the base station apparatus 1 can calculate the received input power value of the desired wave included in the uplink signal to be received in the future.

  On the other hand, when the SIR is included in the reception quality measured by the reception quality measuring unit 152, the received power value of the desired wave and the received power value of the interference wave included in the uplink signal are measured along with the SIR measurement. Is done. The assumed jamming power value calculation unit 182 calculates the received power value of the jamming wave included in the uplink signal to be received in the future based on the measured received power value of the jamming wave.

  For example, the assumed interference wave power value calculation unit 182 samples a number of interference wave power values included in the uplink signal received from the mobile station 2 for each mobile station in real time, and analyzes the fluctuation state to analyze It is possible to predict the power value of the interference wave included in the uplink signal transmitted from the mobile station from which the result is obtained.

  In the case of this method, there is a concern that the line condition between the mobile station 2 and the base station apparatus 1 will change after a certain amount of time has passed. The sampling may be deleted.

  The assumed received power value calculation unit 18 can calculate the assumed received power value by adding the values obtained by the desired wave power value calculation unit 181 and the assumed jamming wave power value calculation unit 182. When calculating the assumed received power value, the desired wave power value and the assumed jamming wave power value may be summed by multiplying both values by respective constants. This assumed received power value is input to gain control section 153. The gain control unit 153 uses the received signal that has been I / Q orthogonal demodulated by the I / Q orthogonal demodulator 14 and the assumed received power value calculated by the assumed received power value calculator 18, as a signal amplifying unit. A gain control signal is output so that the output amplitude of 121 is constant. The gain control signal is converted into an analog signal by a D / A converter and input to the signal amplifier 121.

  FIG. 2 is a flowchart showing the processing flow of this embodiment.

  The uplink signal transmitted from the mobile station 2 is received by the receiving unit 11 (S101) and amplified by the signal amplifying unit 121 (S102). The amplified signal is processed by the A / D converter unit 13 and the I / Q quadrature demodulation unit 14 and input to the baseband circuit unit 15. The signal input to the baseband circuit unit 15 is demodulated and combined by the demodulation / combination unit 151, and the reception quality is measured by the reception quality measurement unit 152 (S103). Based on the measured reception quality, the uplink scheduling unit 16 performs uplink scheduling and generates uplink uplink scheduling information (S104).

  The desired wave power value calculation unit 181 calculates the power value of the desired wave included in the uplink signal to be received in the future based on the uplink scheduling information in the uplink scheduling unit 16 (S105). Based on the measured received power value of the disturbing wave, the assumed disturbing wave power value calculation unit 182 calculates the received power value of the disturbing wave included in the uplink signal to be received in the future (S106). The assumed received power value calculation unit 18 calculates the assumed received power value by adding the calculated desired wave power value and the assumed interference wave power value, and inputs them to the gain control unit 153. The gain control unit 153 uses the signal amplification unit 121 based on the signal demodulated by the I / Q orthogonal demodulation unit 14 and the assumed reception power value calculated by the assumed reception power value calculation unit 18. The gain is controlled in advance so that the output amplitude becomes constant (S107).

  The scheduling information adding unit 17 transmits the uplink scheduling information to the transmission system circuit in order to add the uplink scheduling information to the downlink signal transmitted to the mobile station 2 (S108). The transmitted uplink scheduling information is added to the downlink signal generated by the transmission system circuit and then transmitted to the mobile station 2 (S109), and the processing is completed.

  The effect of the invention of this embodiment will be described. Before receiving the uplink signal, the power value of the desired wave and the assumed interference wave included in the uplink signal is calculated, and the gain of the AGC amplifier is controlled in advance based on the calculation result. Can be converged more quickly and consistently. In addition, since the expected value of the received power value is calculated separately for the desired desired wave and the unnecessary disturbing wave, both the fluctuation of the desired wave and the disturbing wave can be tolerated.

  On the other hand, the techniques described in Patent Documents 1 and 2 do not take into account the power value of the interference wave when assuming the received power value of the uplink signal. In Patent Document 1, transmission output control of a mobile station is performed so that the SIR approaches a target value. However, since it is affected by an interference wave on the uplink, the signal received by the base station apparatus is a burst shape that rises sharply. May be a received signal. Therefore, it can be said that it is inferior to the invention of this embodiment in terms of appropriate gain control for a burst-like received signal that rises sharply.

It is a functional block diagram which shows one Embodiment of the base station apparatus of this invention. It is a flowchart which shows the processing flow in one Embodiment of the base station apparatus of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Base station apparatus 11 Receiving part 12 RF circuit part 121 Signal amplification part 13 A / D converter part 14 I / Q orthogonal demodulation part 15 Baseband circuit part 151 Demodulation / composite part 152 Reception quality measurement part 153 Gain control part 16 Uplink scheduling Unit 17 Scheduling Information Adding Unit 18 Assumed Received Power Value Calculation Unit 181 Desired Wave Power Value Calculation Unit 182 Assumed Interference Wave Power Value Calculation Unit 19 D / A Converter Unit 2 Mobile Station

Claims (6)

Receiving means for receiving the first signal transmitted by the mobile station;
Signal amplifying means for amplifying the first signal received by the receiving means;
Reception quality measuring means for measuring reception quality from the first signal output by the signal amplification means;
Uplink scheduling means for generating uplink scheduling information based on the reception quality;
Scheduling information giving means for giving the scheduling information to a transmission signal transmitted to the mobile station;
Transmitting means for transmitting a signal to which the scheduling information is added to the mobile station;
Based on the scheduling information, desired wave power value calculation means for calculating a power value of a desired wave included in a second signal transmitted by the mobile station at a transmission timing after transmission of the first signal;
Based on the reception quality of the first signal, an assumed interference wave power value calculating means for calculating a power value of the assumed interference wave included in the second signal;
The gain of the signal amplifying means is previously set in consideration of the power value of the desired wave and the power value of the assumed interference wave so that the amplitude of the second signal output from the signal amplifying means is constant. Gain control means for controlling;
A base station apparatus comprising: The base station apparatus according to claim 1,
The reception quality of the first signal measured by the reception quality measuring means has a power value of an interference wave included in the first signal,
The assumed interference wave power value calculating means calculates the power value of the assumed interference wave included in the second signal based on the power value of the interference wave included in the first signal. apparatus. The base station apparatus according to claim 2,
The assumed interference wave power value calculation means stores and analyzes a power value of a prior interference wave included in one or a plurality of signals transmitted by the mobile station at a transmission timing before the transmission of the second signal. A base station apparatus that calculates the assumed interference wave power value included in the second signal. In the base station apparatus of Claim 3,
The base station apparatus, wherein the assumed interference wave power value calculation means deletes the stored power value of the previous interference wave when a predetermined time elapses. In the base station apparatus in any one of Claims 1 thru | or 4,
The base station apparatus, wherein the gain control means controls the gain of the signal amplification means in advance using a value obtained by adding the power value of the desired wave and the power value of the assumed interference wave. A control method for a base station apparatus of a wireless mobile communication system, comprising:
Receiving a first signal transmitted by the mobile station;
Amplifying the received first signal;
Measuring reception quality from the amplified first signal;
Generating uplink scheduling information based on the received quality;
Providing the scheduling information to a transmission signal transmitted to the mobile station;
Transmitting the signal with the scheduling information to the mobile station;
Calculating a power value of a desired wave included in a second signal transmitted by the mobile station at a transmission timing after transmission of the first signal based on the scheduling information;
Calculating a power value of an assumed jamming wave included in the second signal based on the reception quality of the first signal;
Pre-controlling the amplification gain of the second signal in consideration of the power value of the desired wave and the power value of the assumed interference wave so that the amplitude of the amplified second signal is constant; ,
A control method comprising:

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