JP2012004622A - Gain control method and apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gain control method and a gain control apparatus for performing gain control specialized for a specific reception signal in the case where a wireless device receives a group of signals on which a plurality of signals of different frequencies have been superimposed.SOLUTION: A gain control method for controlling a gain when collectively amplifying a group of signals on which a plurality of signals of different frequencies have been superimposed includes: a variable gain amplification step of collectively amplifying the group of signals; a frequency analysis step of performing frequency analysis on a signal output from the variable gain amplification step and measuring a signal level for each of the plurality of signals; and a gain control step of selecting one or more signals from among the plurality of signals as a reference signal on the basis of a preset selection method, and controlling a gain of the variable gain amplification step based on a signal level of the selected reference signal.

Description

  The present invention relates to a gain control technique for a variable gain amplifier.

  In a conventional radio apparatus, when the gain of a received signal is controlled by a variable gain amplifier, the bandwidth of the input signal to the variable gain amplifier or the output signal from the variable gain amplifier is reduced to the channel bandwidth by a filter or the like. The signal is limited, the band-limited signal level is measured in the time domain, and gain control is performed so that the output signal level from the variable gain amplifying unit is constant (see Non-Patent Document 1 or 2).

FIG. 18 shows an example of a conventional wireless device. The radio apparatus of FIG. 18 includes an RF unit 10 including at least a variable gain amplification unit 12 and a signal level determination unit 14, an AD conversion unit 16, and a demodulation processing unit 18.
The signal received by the RF unit 10 is subjected to gain control by the variable gain amplification unit 12 so that the output signal level from the RF unit 10 is constant. In the previous stage of output from the RF unit 10 to the AD conversion unit 16, the signal level is determined by the signal level determination unit 14, and the control value of the variable gain amplification unit 12 is changed based on the determination result. The received signal converted into a digital signal by the AD conversion unit 16 is demodulated by the demodulation processing unit 18.

  FIG. 19 is an example of a processing flow of conventional gain control. The wireless device measures the received signal level in step S22. In step S24, a control value of the variable gain amplifying unit in the RF unit corresponding to the measured received signal level is set, and gain control is executed.

As described above, in the conventional radio apparatus, the signal level is measured in the time domain with respect to the input signal to the variable gain amplification unit or the output signal from the variable gain amplification unit, and the output signal from the variable gain amplification unit. Gain control is performed to keep the level constant.
The input signal to the variable gain amplifying unit or the output signal from the variable gain amplifying unit is band-limited by a filter or the like, and then the signal level is measured in the time domain.

Fujimoto, et al., “Development of indoor FOMA booster device”, NTT DoCoMo Technical Journal, Vol. 13, no. 3, pp. 25-30. Masuda, et al. “A Study on Digital AGC in PHS Using Quadrature Demodulation”, 1997 IEICE General Conference, B-5-140.

  However, when the radio apparatus collectively receives a signal group in which a plurality of signals having different frequencies are superimposed, the band is received in a wide band. Therefore, the band cannot be limited to the channel bandwidth by a filter or the like. Therefore, in the conventional gain control based on the signal level determination based on the time domain, it is possible to execute collective gain control for all the received signals, but it is not possible to execute gain control specialized for the specified received signals. There is a problem.

For example, each received signal level of the superimposed signal group may be large or small. At this time, in the conventional gain control, since the gain control for all signals is performed collectively, the amplification for the maximum level signal is excessive and the signal is distorted, or the amplification for the minimum level signal is not performed. In some cases, the SNR of the signal is deteriorated due to shortage.
In addition, undesired signals may be superimposed on the superimposed signal group, and the signal level of the undesired received signal may affect the gain control of the variable gain amplifying unit.

  The present invention has been made in view of such circumstances, and an object thereof is to specialize in a specified received signal when a radio apparatus collectively receives a signal group in which a plurality of signals having different frequencies are superimposed. An object of the present invention is to provide a gain control method and a gain control apparatus that execute gain control.

The present invention was made to solve the above-described problems, and the invention according to claim 1
A gain control method used in a gain control apparatus for controlling a gain when collectively amplifying a signal group in which a plurality of signals having different frequencies are superimposed, a variable gain amplification procedure for amplifying the signal group at a time, Based on a frequency analysis procedure for performing signal analysis on the signal output from the variable gain amplification procedure and measuring a signal level for each of the plurality of signals, and a preset selection method, A gain control procedure that selects one or more of the signals as a reference signal and controls the gain of the variable gain amplification procedure based on the signal level of the selected reference signal. It is a control method.

  According to a second aspect of the present invention, in the gain control procedure, when the gain of the variable gain amplification procedure is controlled, the signal level of the reference signal and a preset gain control increase control or decrease control are controlled. 2. The gain control method according to claim 1, wherein a gain increase threshold and a gain decrease threshold for determining the gain are compared, and the gain is controlled based on the comparison result.

  According to a third aspect of the present invention, in the gain control procedure, when one or more signals are selected as the reference signal from the plurality of signals, the signal level having the highest signal level is selected from the plurality of signals. 3. The gain control method according to claim 1, wherein a large signal is selected as the reference signal.

  According to a fourth aspect of the present invention, in the gain control procedure, when one or more signals are selected as the reference signal from the plurality of signals, the signal level having the highest signal level is selected from the plurality of signals. 3. The gain control method according to claim 1, wherein a small signal is selected as the reference signal.

  According to a fifth aspect of the present invention, in the gain control procedure, the signal level of the plurality of signals is compared with the gain increase threshold value and the gain decrease threshold value, and the gain is obtained from the comparison result for each of the plurality of signals. 3. The gain control method according to claim 1, wherein the increase control or decrease control and the gain control value are calculated, and the most control among the comparison results is selected.

  According to a sixth aspect of the present invention, in the gain control procedure, when one or more signals are selected as the reference signal from the plurality of signals, each signal of the superimposed signal group is previously stored. 3. The gain control method according to claim 1, wherein a signal having a high priority is selected as the reference signal from the plurality of signals based on a set priority.

  The invention according to claim 7 is provided with a plurality of frequency conversion procedures for performing frequency conversion of the superimposed signal group for each frequency band in a previous stage of signal input of the variable gain amplification procedure, and the frequency conversion procedure Includes at least a variable attenuator procedure or a second variable gain amplification procedure, and in the variable attenuator procedure, a signal level of a received signal for each frequency band assigned to the frequency conversion procedure is adjusted, and the second variable gain In the amplification procedure, the signal level of the received signal for each frequency band assigned to the frequency conversion procedure is collectively amplified, and the reference selected for each frequency band of the signal output of the frequency conversion procedure in the gain control procedure The signal is compared with a predetermined reference level so that the reference signal is equal to the reference level. A control value of the attenuator procedure or the second variable gain amplification procedure and a control value of the variable gain amplification procedure are calculated, and based on the calculated control value, the variable attenuator procedure or the second variable gain amplification procedure 7. The gain control method according to claim 1, wherein the variable gain amplification procedure is controlled.

  The invention according to claim 8 includes an AD conversion procedure for converting the signal output of the variable gain amplification procedure from an analog signal to a digital signal, and the frequency analysis procedure is performed on the signal output from the AD conversion procedure. Analyzing the frequency and measuring the signal level for each of the plurality of signals, the gain control procedure compares the previous signal level for each of the plurality of signals with a preset distortion occurrence threshold, and is equal to or higher than the distortion occurrence threshold. When the signal at the signal level is detected, an unnecessary wave is generated from the frequency information of the signal, or the unnecessary wave is generated based on a signal obtained by correcting the phase of the signal based on the frequency characteristic of the variable gain amplification procedure. 7. The gain control method according to claim 1, wherein the gain control method generates and removes the unnecessary wave from the signal output. 8.

  The invention according to claim 9 is a gain control device for controlling a gain when collectively amplifying a signal group in which a plurality of signals having different frequencies are superimposed, and a variable gain amplifying unit for amplifying the signal group at a time And a frequency analysis unit that performs frequency analysis on the signal output from the variable gain amplification unit and measures a signal level for each of the plurality of signals, and a plurality of the plurality of the plurality of signals based on a preset selection method. A gain control unit that selects one or more of the signals from the signal as a reference signal, and controls the gain of the variable gain amplification unit based on the signal level of the selected reference signal. Is a gain control device.

The invention according to claim 10 is provided with a plurality of frequency conversion units that perform frequency conversion on the superimposed signal group for each frequency band in a preceding stage of signal input of the variable gain amplification unit, and the frequency conversion unit Includes at least a variable attenuator unit or a second variable gain amplifier unit,
The variable attenuator unit adjusts the signal level of the received signal for each frequency band assigned to the frequency converter, and the second variable gain amplifier unit receives the signal for each frequency band assigned to the frequency converter. The signal level of the signal is collectively amplified, and the gain control unit compares the reference signal selected for each frequency band of the signal output of the frequency conversion unit with a predetermined reference level, and the reference signal Is calculated to be equal to the reference level, the control value of the variable attenuator unit or the second variable gain amplification unit and the control value of the variable gain amplification unit are calculated, and based on the calculated control value, The gain control device according to claim 9, wherein the variable attenuator unit or the second variable gain amplifying unit and the variable gain amplifying unit are controlled.

  The invention according to claim 11 includes an AD conversion unit that converts the signal output of the variable gain amplification unit from an analog signal into a digital signal, and the frequency analysis unit outputs a signal output from the AD conversion unit. Analyzing the frequency and measuring the signal level for each of the plurality of signals, the gain control unit compares the previous signal level for each of the plurality of signals with a preset distortion occurrence threshold, and is equal to or higher than the distortion occurrence threshold. When the signal at the signal level is detected, an unnecessary wave is generated from the frequency information of the signal, or the unnecessary wave is generated based on a signal obtained by correcting the phase of the signal based on the frequency characteristic of the variable gain amplifier. The gain control device according to claim 9, wherein the gain control device generates and removes the unnecessary wave from the signal output.

  According to the present invention, even when a signal group in which a plurality of signals having different frequencies are superimposed is collectively amplified by the variable gain amplifier, the gain control unit selects the reference signal from each of the frequency-analyzed signals. Since gain control is executed based on the reference signal, gain control specialized for the specified received signal can be executed to improve the signal characteristics after amplification.

Further, according to the present invention, flexible gain control can be performed such that priority is set at the radio system or user level, and signal gain control is performed based on the priority.
Furthermore, according to the present invention, when a plurality of radio system signals are received in a lump, a radio apparatus is required to have a high dynamic range. Since the level adjustment control is also performed, the load of the dynamic range in the RF unit can be reduced.
Furthermore, according to the present invention, it is possible to improve reception characteristics by predicting signal distortion during gain control and removing unnecessary waves by signal processing.

It is a schematic block diagram which shows the structure of the radio | wireless apparatus containing the gain control apparatus by 1st Embodiment of this invention. It is explanatory drawing explaining the outline | summary of the gain control method in 1st Embodiment of this invention. FIG. 3 is an example of a process flowchart of the gain control method described in FIG. 2. In 1st Embodiment of this invention, it is explanatory drawing explaining the outline | summary of the gain control method in case the conditions which select a reference signal are the signals of the largest signal level. FIG. 5 is an example of a processing flowchart of the gain control method described in FIG. 4. In 1st Embodiment of this invention, it is explanatory drawing explaining the outline | summary of the gain control method in case the conditions which select a reference signal are the signals of the smallest signal level. FIG. 7 is an example of a process flowchart of the gain control method described in FIG. 6. In 1st Embodiment of this invention, it is explanatory drawing explaining the outline | summary of the gain control method in the case of carrying out gain control never many of the result of having performed the threshold determination of the signal level for every signal. FIG. 9 is an example of a process flow diagram of the gain control method described in FIG. 8. In 1st Embodiment of this invention, it is explanatory drawing explaining the outline | summary of the gain control method in the case of selecting a reference signal based on the priority preset to the signal to receive. It is an example of the processing flowchart of the gain control method described in FIG. It is a schematic block diagram which shows the structure of the radio | wireless apparatus containing the gain control apparatus by 2nd Embodiment of this invention. It is explanatory drawing explaining the outline | summary of the gain control method in 2nd Embodiment of this invention. FIG. 14 is an example of a process flow diagram of a method for controlling a signal level of a received signal with a variable attenuator and a variable gain amplifier in FIG. 13. It is a schematic block diagram which shows the structure of the radio | wireless apparatus containing the gain control apparatus by 3rd Embodiment of this invention. It is explanatory drawing explaining the outline | summary of the gain control method in 3rd Embodiment of this invention. FIG. 17 is an example of a process flow diagram for control related to unnecessary wave removal in the description of FIG. 16. It is an example of the schematic block diagram which shows the structure of the conventional radio | wireless apparatus. It is an example of the processing flowchart of the conventional gain control.

  In the description of the following embodiments, description will be given by the configuration of gain control in the wireless receiver. However, the present invention is not limited to a wireless receiver configuration, and can be applied to any field such as gain control in wired transmission and gain control in a device.

<First Embodiment>
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic block diagram showing a configuration of a radio apparatus including a gain control apparatus according to the first embodiment of the present invention.

  The radio apparatus includes an RF unit 100 including a variable gain amplification unit 102, an AD conversion unit 104, a frequency analysis unit 106, a gain control unit 108, a demodulation processing unit 110, and a radio system database 112.

The received signal received by the RF unit 100 is input to the variable gain amplifying unit 102 provided in the RF unit 100, and gain control is performed. The received signal that has been gain-controlled and level-adjusted to a certain magnitude is input to the AD converter 104 and the frequency analyzer 106.
The AD conversion unit 104 converts the reception signal input from the variable gain amplification unit 102 from analog data to digital data, and outputs the digital data to the demodulation processing unit 110.
The demodulation processing unit 110 demodulates the reception signal input from the AD conversion unit 104 and converted into digital data.

  On the other hand, the frequency analysis unit 106 performs frequency analysis on the reception signal input from the variable gain amplification unit 102 to measure the signal level of the signal for each frequency included in the reception signal, and the gain control unit 108 indicates the measurement result. Output.

The gain control unit 108 is a measurement condition input from the frequency analysis unit 106 based on a selection condition registered in the wireless system database 112 and a reference signal selection condition set according to the priority of the wireless system. The signal level of the signal for each frequency as a result is detected, and a signal corresponding to the selection condition is selected as a reference signal based on the detected result.
The gain control unit 108 also compares the condition for comparison with the reference signal registered in the wireless system database 112 and the signal level of the selected reference signal, and sets the gain control determined from the comparison result. The value is output to the variable gain amplification unit 102. The variable gain amplifying unit 102 amplifies the received signal based on the set gain control.
In this embodiment, a gain increase threshold and a gain decrease threshold are used as conditions for comparison with the reference signal.

  The frequency analysis unit 106 may use data converted from analog data to digital data in the AD conversion unit 104 instead of the reception signal input from the variable gain amplification unit 102.

FIG. 2 is an explanatory diagram for explaining the outline of the gain control method according to the first embodiment of the present invention.
First, the frequency analysis unit 106 is a signal group in which a plurality of signals are superimposed in a wide frequency range (in the case of radio, it corresponds to a received radio wave received. Hereinafter, it is referred to as a received radio wave received, but can be dealt with in the embodiment. The signal group is not limited to the received radio wave).
At this time, the frequency analysis unit 106 uses fast Fourier transform, short-time Fourier transform, discrete Fourier transform, wavelet transform, Wigner distribution analysis, or a combination thereof as a frequency analysis method.

In FIG. 2A, the vertical axis represents signal level (amplitude), and the horizontal axis represents time. The vertical axis in FIG. 2B is the signal level (amplitude), and the horizontal axis is the frequency.
FIG. 2A shows received radio waves. FIG. 2B shows an example in which five signals (signal S1 to signal S5) are included in the received radio wave as a result of frequency analysis of the received radio wave.
The gain reduction threshold shown in FIG. 2B is a threshold used for determination to decrease the gain in the variable gain amplification unit 102, and the gain increase threshold is a threshold used for determination to increase the gain in the variable gain amplification unit 102. It is.

Here, the gain control unit 108 selects the signal S5 as a reference signal when determining gain control. Therefore, the gain control unit 108 detects the signal level of the signal S5, which is the reference signal, for a certain period, and determines increase / decrease in gain based on the detection result.
When determining the increase or decrease in gain, the gain control unit 108 compares the average value of the signal level of the reference signal within the detection period with the gain decrease threshold and the gain increase threshold, and increases or decreases the gain from the comparison result. Judge whether to execute or not.
The gain control unit 108 determines the gain control amount based on the currently set gain control value, the signal level (amplitude value) of the received radio wave, the reference signal level (amplitude value), or a combination thereof.

  In this way, the gain control unit 108 notifies or sets the variable gain amplifying unit 102 with the result of determining the gain increase / decrease and the control value for determining the gain control amount, and performs gain control.

In FIG. 2, as a result of the determination based on the signal S5, since the signal level of the signal S5 is smaller than the gain increase threshold, the variable gain amplification unit 102 determines the gain increase control and increases the amplification amount of the variable gain amplification unit 102. Control.
FIG. 2C shows an example of the signal level of each signal after the increase control.

FIG. 3 is an example of a processing flowchart of the gain control method described in FIG.
First, the frequency analysis unit 106 performs frequency analysis on the received radio wave input from the variable gain amplification unit 102 (step S102).

  Next, the gain control unit 108 detects the amplitude value of each signal input from the frequency analysis unit 106 for a certain period and calculates the average value of each signal. Next, the gain control unit 108 selects a signal corresponding to the selection condition as a reference signal. Then, the gain control unit 108 compares the average value of the reference signal with the gain increase threshold value, and if it is equal to or less than the gain increase threshold value, the process proceeds to step S108. Further, the gain control unit 108 compares the average value of the reference signal with the gain increase threshold value, and if it is equal to or greater than the gain increase threshold value, the process proceeds to step S106 (step S104).

  Subsequently, when it is determined in step S104 that the process proceeds to step S106, the gain control unit 108 compares the average value of the reference signal selected in step S104 with the gain reduction threshold value, and the average value of the reference signal is the gain. If it is equal to or greater than the decrease threshold, the process proceeds to step S108. If the average value of the reference signals is equal to or smaller than the gain reduction threshold, gain control unit 108 ends the process without performing gain control (step S106).

  Further, when it is determined in step S104 and step S106 that the process proceeds to step S108, the gain control unit 108 sets the current set value of the variable gain amplification unit 102, the signal level (amplitude value) of the received radio wave, and the gain control target. The control value of the variable gain amplifying unit 102 is determined based on the signal level (amplitude value) of the reference signal, or a combination of two or more thereof, and the control value is notified or set to the variable gain amplifying unit 102 (step S108). ).

  As described above, even when the variable gain amplification unit 102 collectively amplifies a signal group in which a plurality of signals having different frequencies are superimposed, the gain control unit 108 of the first embodiment A reference signal is selected from the frequency-analyzed signals, and gain control is executed based on the reference signal. Thereby, the gain control apparatus of the first embodiment can execute gain control specialized for the specified received radio wave.

  In step S102, the frequency analysis unit 106 performs frequency analysis using data converted from analog data to digital data in the AD conversion unit 104 instead of the received radio wave input from the variable gain amplification unit 102. Also good.

In step S104, the gain control unit 108 determines whether the reference signal is less than or equal to the gain increase threshold within the detection period, instead of comparing the average value of the reference signal with the gain increase threshold. You may determine whether it is more than the number determined to increase.
Further, in step S106, the gain control unit 108, instead of making a determination by comparing the average value of the reference signal with the gain increase threshold value, sets a preset number of times that the reference signal exceeds the gain decrease threshold value within the detection period. You may determine whether it is more than the number of times determined to decrease.

  A method for selecting a reference signal or a method for determining gain control will be described with reference to FIGS. A case where the reference signal is selected based on the magnitude of the signal level will be described with reference to FIGS. A case will be described with reference to FIGS. 8 to 9 where each signal is used as a reference signal and control is never performed for many signal levels for each signal. A case where the reference signal is selected based on the priority set in advance in the wireless system will be described with reference to FIGS. 10 to 11.

  First, the outline of the gain control method when the condition for selecting the reference signal is a signal having the highest signal level in the first embodiment of the present invention described above will be described with reference to FIG. The vertical axis and the horizontal axis in FIGS. 4A and 4B are the same as the vertical axis and the horizontal axis in FIGS. 2A and 2B. FIG. 4A shows received radio waves. FIG. 4B shows an example in which five signals (signal S1 to signal S5) are included in the received radio wave as a result of frequency analysis of the received radio wave.

Here, the gain control unit 108 selects the signal S1 having the highest signal level among the five signals as the reference signal for determining the gain control. Therefore, the signal level of the signal S1 is detected for a certain period, and the increase / decrease in gain is determined based on the detection result.
The gain increase / decrease is determined by comparing the average value of the signal level of the reference signal within the detection period with the gain decrease threshold and the gain increase threshold, and determining whether to increase / decrease the gain based on the comparison result.
The gain control amount is determined based on the currently set gain control value, the signal level (amplitude value) of the received radio wave, the reference signal level (amplitude value), or a combination thereof.

  In this way, the gain control unit 108 notifies or sets the variable gain amplifying unit 102 with the result of determining the gain increase / decrease and the control value for determining the gain control amount, and performs gain control.

In FIG. 4, since the signal level of the signal S1 is larger than the gain increase threshold and smaller than the gain decrease threshold as a result of the determination based on the signal S1, the gain control unit 108 performs neither gain increase control nor gain decrease control. And the gain control value of the variable gain amplifying unit 102 is not changed from the current setting.
FIG. 4C is an example of the signal level of each signal after control. Since the control value is not changed, the signal level of each signal is the same as that in FIG. 4B.

FIG. 5 is an example of a processing flowchart of the gain control method described in FIG.
First, the frequency analysis unit 106 performs frequency analysis on the received radio wave input from the variable gain amplification unit 102 (step S202).

  Next, the gain control unit 108 detects the amplitude value of each signal input from the frequency analysis unit 106 for a certain period and calculates the average value of each signal. Next, the gain control unit 108 selects a signal having the highest average value among the signals as a reference signal. Then, the gain control unit 108 compares the average value of the reference signal with the gain increase threshold value, and if it is equal to or less than the gain increase threshold value, the process proceeds to step S208. Further, the gain control unit 108 compares the average value of the reference signal with the gain increase threshold value, and if it is equal to or greater than the gain increase threshold value, the process proceeds to step S206 (step S204).

  Subsequently, when it is determined in step S204 that the process proceeds to step S206, the gain control unit 108 compares the average value of the reference signal selected in step S204 with the gain reduction threshold, and the average of the reference signal is a gain reduction. If it is equal to or greater than the threshold value, the process proceeds to step S208. If the average of the reference signals is equal to or less than the gain reduction threshold, the gain control unit 108 ends the process without performing gain control (step S206).

  Further, when it is determined in step S204 and step S206 that the process proceeds to step S208, the gain control unit 108 sets the current setting value of the variable gain amplification unit 102, the signal level (amplitude value) of the received radio wave, and the gain control target. The control value of the variable gain amplifying unit 102 is determined based on the signal level (amplitude value) of the reference signal, or a combination of two or more thereof, and the control value is notified or set to the variable gain amplifying unit 102 (step S208). ).

  In this way, when the gain control apparatus according to the first embodiment selects the signal having the highest signal level as the reference signal, the gain control unit 108 decreases the gain of the reference signal by a gain increase threshold or more. Gain control is executed so as to be in the range below the threshold. As a result, the gain control apparatus according to the first embodiment can suppress excessive amplification of the signal having the maximum signal level, and can prevent distortion of the signal.

  In step S202, step S204, or step S206 in FIG. 5, the processing method may be changed in the same manner as in step S102, step S104, or step S106 in FIG.

  Next, the outline of the gain control method when the condition for selecting the reference signal is a signal having the smallest signal level in the first embodiment of the present invention described above will be described with reference to FIG. The vertical axis and the horizontal axis in FIGS. 6A and 6B are the same as the vertical axis and the horizontal axis in FIGS. 2A and 2B. FIG. 6A shows received radio waves. FIG. 6B shows an example in which five signals (signal S1 to signal S5) are included in the received radio wave as a result of frequency analysis of the received radio wave.

Here, the gain control unit 108 selects the signal S4 having the lowest signal level among the five signals as a reference signal for determining gain control. Therefore, the signal level of the signal S4 is detected for a certain period, and the increase / decrease in gain is determined based on the detection result.
The gain increase / decrease is determined by comparing the average value of the signal level of the reference signal within the detection period with the gain decrease threshold and the gain increase threshold, and determining whether to increase / decrease the gain based on the comparison result.
The gain control amount is determined based on the currently set gain control value, the signal level (amplitude value) of the received radio wave, the reference signal level (amplitude value), or a combination thereof.

  In this way, the gain control unit 108 notifies or sets the result of determining the gain increase / decrease and the control value that determines the gain control amount to the variable gain amplifying unit 102, and performs gain control.

In FIG. 6, as a result of the determination based on the signal S4, the signal level of the signal S4 is smaller than the gain increase threshold value. Therefore, the gain control unit 108 determines the gain increase control and controls the increase of the amplification amount of the variable gain amplification unit 102. .
FIG. 6C is an example of the signal level of each signal after control, and the signal level of each signal is higher than that in FIG. 6B.

FIG. 7 is an example of a process flow diagram of the gain control method described in FIG.
First, the frequency analysis unit 106 performs frequency analysis on the received radio wave input from the variable gain amplification unit 102 (step S302).

  Next, the gain control unit 108 detects the amplitude value of each signal input from the frequency analysis unit 106 for a certain period and calculates the average value of each signal. Next, the gain control unit 108 selects a signal having the lowest average value among the signals as a reference signal. Then, the gain control unit 108 compares the average value of the reference signal with the gain increase threshold value, and if it is equal to or less than the gain increase threshold value, the process proceeds to step S308. Further, the gain control unit 108 compares the average value of the reference signal with the gain increase threshold value, and if it is equal to or greater than the gain increase threshold value, the process proceeds to step S306 (step S304).

  Subsequently, when it is determined in step S304 that the process proceeds to step S306, the gain control unit 108 compares the average value of the reference signal selected in step S304 with the gain reduction threshold value, and the average value of the reference signal is the gain. If so, the process proceeds to step S308. If the gain control unit 108 is equal to or smaller than the average gain reduction threshold value of the reference signal, the gain control unit 108 ends the process without performing gain control (step S306).

  Further, when it is determined in step S304 and step S306 that the process proceeds to step S308, the gain control unit 108 sets the current setting value of the variable gain amplification unit 102, the signal level (amplitude value) of the received radio wave, and the gain. The control value of the variable gain amplifying unit 102 is determined based on the signal level (amplitude value) of the reference signal to be controlled, or a combination of two or more thereof, and the control value is notified or set to the variable gain amplifying unit 102 ( Step S308).

  As described above, when the gain control apparatus according to the first embodiment selects the signal having the lowest signal level as the reference signal, the gain control unit 108 sets the reference signal to a gain increase threshold value or more and a gain decrease threshold value or less. Gain control is performed so as to be within the range. As a result, the gain control apparatus according to the first embodiment can suppress the amplification of the minimum level signal from becoming insufficient, and can prevent the SNR of the signal from deteriorating.

  In step S302, step S304, or step S306 in FIG. 7, the processing method may be changed in the same manner as in step S102, step S104, or step S106 in FIG.

  Next, referring to FIG. 8, in the first embodiment of the present invention described above, the condition for executing the gain control is to determine the gain control by comparing the signal level and the gain control threshold for each signal, and the determination An outline of the gain control method in the case where gain control is performed based on the largest number of determination results among the results will be described.

The vertical axis and the horizontal axis in FIGS. 8A and 8B are the same as the vertical axis and the horizontal axis in FIGS. 2A and 2B.
FIG. 8A shows received radio waves. FIG. 8B shows an example in which five signals (signal S1 to signal S5) are included in the received radio wave as a result of frequency analysis of the received radio wave.
Here, the gain control unit 108 selects all five signals (signal S1 to signal S5) as reference signals for determining gain control. Therefore, the signal levels of all five signals are detected for a certain period, and the increase / decrease in gain is determined for each signal based on the detection result.

The gain increase / decrease is determined by comparing the average value of the signal level of the reference signal within the detection period with the gain decrease threshold and the gain increase threshold, and determining the gain increase / decrease for each signal from the comparison result.
Then, a majority decision is made for each signal, and whether to increase or decrease the gain is determined based on the control with the larger determination result.
The gain control amount includes the signal level (amplitude value) of a plurality of signals selected by majority vote, the signal level (amplitude value) of a signal further selected from the plurality of signals, and the currently set gain control value. It is determined based on the signal level (amplitude value) of the received radio wave or a combination thereof.

  In this way, the gain control unit 108 notifies or sets the variable gain amplifying unit 102 with the result of determining the gain increase / decrease and the control value for determining the gain control amount, and performs gain control.

In FIG. 8, the gain control unit 108 determines that the three signals S1, S2, and S3 are not changed in gain control, and the two signals S4 and S5 are gain increase control. The determination result of the three signals is selected by majority decision, and the gain control value of the variable gain amplifier 102 is not changed from the current setting.
FIG. 8C shows an example of the signal level of each signal after control, and since the control value is not changed, the signal level of each signal is the same as that in FIG. 8B.

FIG. 9 is an example of a processing flowchart of the gain control method described in FIG.
First, the frequency analysis unit 106 performs frequency analysis on the received radio wave input from the variable gain amplification unit 102 (step S402).
Next, the gain control unit 108 detects the average value of the amplitude value or signal level of each signal for a certain period for each signal input from the frequency analysis unit 106, and selects each signal as a reference signal. The gain control unit 108 compares the amplitude value of each reference signal or the average value of the signal levels with a gain increase threshold value, determines whether the gain increase threshold value or less is satisfied, and holds the determination result for each signal. As a determination method, there is a method based not on the average value but on the number of times that the gain increase threshold or less is reached (step S404).

  Next, the gain control unit 108 compares the amplitude value of each reference signal or the average value of the signal levels with the gain reduction threshold, determines whether or not the gain reduction threshold is exceeded, and holds the determination result for each signal. As a determination method, there is a method based not on the average value but on the number of times that the gain reduction threshold is reached (step S406).

Next, the gain control unit 108 selects the determination result of the most signals from the determination results for each signal held in steps S404 and S406 (step S408).
Next, the gain control unit 108 determines whether or not it is necessary to change the gain control value of the variable gain amplification unit 102 based on the determination result selected in step S408 (step S410).

  If it is determined in step S410 that the gain control value needs to be changed, the gain control unit 108 determines the level of the received radio wave, the signal subjected to gain control (if there are a plurality of signals to be processed, one of them). The control value of the variable gain amplifying unit 102 is calculated based on the signal having the highest signal level, the signal level being the lowest, or the average value thereof, or a combination thereof, and the control value is notified or set to the variable gain amplifying unit. (Step S420).

  If it is determined in step S410 that it is not necessary to change the gain control value, the gain control unit 108 ends the process without executing the change of the gain control value.

  As described above, in the gain control apparatus according to the first embodiment, the gain control unit 108 determines gain control from the comparison between the signal level and the gain control threshold for each signal, and the most among the determination results. Gain control is executed based on the determination result. As a result, the gain control apparatus according to the first embodiment can prevent a large number of signals from being excessively amplified and distorted or insufficiently amplified to deteriorate the SNR.

  In step S402 in FIG. 9, the processing method may be changed in the same manner as in step S102 in FIG.

  Next, referring to FIG. 10, in the first embodiment of the present invention described above, the reference signal selection condition is based on the priority set in advance for the signal to be received, and the reference signal in the order of the signal having the highest priority. The outline of the gain control method for the case of selecting as will be described.

The vertical axis and the horizontal axis in FIGS. 10A and 10B are the same as the vertical axis and the horizontal axis in FIGS. 2A and 2B.
FIG. 10A shows received radio waves. FIG. 10B shows an example in which five signals (signal S1 to signal S5) are included in the received radio wave as a result of frequency analysis of the received radio wave.
In this control method, the priority of the signal is set according to the wireless system received in advance. As shown in FIG. 10B, the signal of priority 1 is the signal S5 and of priority 2. The signal is an example in which the signal S4, the signal S1, the signal S2, and the signal S3 are in descending order of priority.

  Here, the gain control unit 108 selects the signal S5 having the highest signal priority among the five signals as the reference signal for determining the gain control. Therefore, the signal level of the signal S5 is detected for a certain period, and the increase / decrease in gain is determined based on the detection result.

The gain increase / decrease is determined by comparing the average value of the signal level of the reference signal within the detection period with the gain decrease threshold and the gain increase threshold, and determining whether to increase / decrease the gain based on the comparison result.
The gain control amount is determined based on the currently set gain control value, the signal level (amplitude value) of the received radio wave, the reference signal level (amplitude value), or a combination thereof.

  In this way, the gain control unit 108 notifies or sets the result of determining the gain increase / decrease and the control value that determines the gain control amount to the variable gain amplifying unit 102, and performs gain control.

In FIG. 10, as a result of the determination based on the signal S5, the signal level of the signal S5 is smaller than the gain increase threshold value. Therefore, the gain control unit 108 determines the gain increase control and increases the amplification amount of the variable gain amplification unit 102. .
FIG. 10C shows an example of the signal level of each signal after control. The signal level of each signal is higher than that in FIG. 10B.

  Note that the gain control unit 108 selects, as the reference signal, the reference signal having the highest priority among the input signals. Therefore, for example, when the signal S5 is not input, the signal S4 having the priority 2 selects the reference signal. Further, when the priority level signal S4 is not input, the priority level signal S1 is selected as the reference signal.

FIG. 11 is an example of a processing flowchart of the gain control method described in FIG.
First, the frequency analysis unit 106 performs frequency analysis on the received radio wave input from the variable gain amplification unit 102 (step S502).

Next, the gain control unit 108 gives a preset priority to the wireless system based on the frequency information of each signal input from the frequency analysis unit 106. A signal having the highest priority is selected as a reference signal from the priorities assigned to the signals.
Next, the gain control unit 108 detects the amplitude value of the selected reference signal for a certain period and calculates the average value of the reference signal.
Then, the gain control unit 108 compares the average value of the reference signal with the gain increase threshold value, and if it is equal to or less than the gain increase threshold value, the process proceeds to step S508.
Further, the gain control unit 108 compares the average value of the reference signal with the gain increase threshold value, and if it is equal to or greater than the gain increase threshold value, the process proceeds to step S506 (step S504).

  Subsequently, when it is determined in step S504 that the process proceeds to step S506, the gain control unit 108 compares the average value of the reference signal selected in step S504 with the gain reduction threshold, and the average value of the reference signal is gain. If it is equal to or greater than the decrease threshold, the process proceeds to step S508. If the gain control unit 108 is equal to or less than the average gain reduction threshold value of the reference signal, the gain control unit 108 ends the process without performing gain control (step S506).

  Further, when it is determined in step S504 and step S506 that the process proceeds to step S508, the gain control unit 108 sets the current setting value of the variable gain amplification unit 102, the signal level (amplitude value) of the received radio wave, and the gain control target. The control value of the variable gain amplifying unit 102 is determined based on the signal level (amplitude value) of the reference signal, or a combination of two or more thereof, and the control value is notified or set to the variable gain amplifying unit 102 (step S508). ).

  As described above, when the gain control apparatus according to the first embodiment selects a preset high-priority signal as a reference signal, the gain control unit 108 selects the reference signal as a gain increase threshold or more. Gain control is executed so as to be in the following range. As a result, the gain control apparatus according to the first embodiment can prevent a signal having a high priority from being excessively amplified and distorted, or from being insufficiently amplified to deteriorate the SNR.

In step S502, step S504, or step S506 in FIG. 11, the processing method may be changed in the same manner as in step S102, step S104, or step S106 in FIG.

Second Embodiment
Hereinafter, a second embodiment of the present invention will be described with reference to the drawings. FIG. 12 is a schematic block diagram showing a configuration of a radio apparatus including a gain control apparatus according to the second embodiment of the present invention.

The radio apparatus includes an RF unit 200 including a frequency conversion unit 214 and a variable gain amplification unit 202, an AD conversion unit 204, a frequency analysis unit 206, a gain control unit 208, a demodulation processing unit 210, and a radio system database 212. .
The frequency conversion unit 214 includes a variable attenuator 216, a variable gain amplification unit 217 (second variable gain control unit), or both, and further includes a low noise amplifier, a filter, a mixer, and the like.

  The variable gain amplification unit 202, AD conversion unit 204, frequency analysis unit 206, gain control unit 208, demodulation processing unit 210, and radio system database 212 shown in FIG. 12 are the same as those in the first embodiment shown in FIG. It corresponds to the amplification unit 102, AD conversion unit 104, frequency analysis unit 106, gain control unit 108, demodulation processing unit 110, and radio system database 112, respectively. Further, the RF unit 200 shown in FIG. 12 corresponds to the RF unit 100 of the first embodiment shown in FIG. 1, but the RF unit 200 is different in that it includes a frequency conversion unit 214. The description of the same configuration among the corresponding configurations is omitted.

Reception signals received by the RF unit 200 are input to a plurality of frequency conversion units 214 provided in the RF unit 200. The plurality of frequency conversion units 214 assign the received signal to each of a plurality of frequency bands, and perform frequency conversion for each assigned frequency band. Further, the frequency conversion unit 214 adjusts the signal level using the variable attenuator 216, the variable gain amplification unit 217, or both included in the frequency conversion unit 214 when performing frequency conversion.
The variable gain amplifying unit 202 receives the received signal that has been frequency-converted and level-adjusted by the frequency converting unit 214, and performs gain control.
The variable gain amplifying unit 202 outputs the received signal whose gain is controlled and level-adjusted to a constant magnitude to the AD converting unit 204 and the frequency analyzing unit 206.

The gain control unit 208 is a measurement condition input from the frequency analysis unit 206 based on the selection condition registered in the wireless system database 212 and based on the selection condition of the reference signal set according to the priority of the wireless system. The signal level of the signal for each frequency as a result is detected, and based on the detected result, a signal corresponding to the selection condition is selected as a reference signal for each frequency band assigned by the plurality of frequency converters 214.
Further, the gain control unit 208 compares the reference signal selected for each frequency band with the reference level based on the reference level registered in the wireless system database 212 for adjusting the signal level of the reference signal.
Furthermore, the gain control unit 208 compares the reference signal and the reference level, and the variable attenuator 216 and the variable gain amplification so that the signal levels of the plurality of reference signals selected for each frequency band are equal to the reference level. The setting value for the unit 217 or both and the setting value for gain control to the variable gain amplifying unit 202 are output.

  Thus, after adjusting the signal level of the reference signal for each frequency band, the gain control unit 208 performs gain control similar to that described in the first embodiment.

  Note that the frequency analysis unit 206 may use data converted from analog data to digital data by the AD conversion unit 204 instead of the reception signal input from the variable gain amplification unit 202.

FIG. 13 is an explanatory diagram for explaining the outline of the gain control method according to the second embodiment of the present invention.
In the second embodiment, the received radio wave input from the antenna is divided into a plurality of frequency bands, so that the signal level included in each frequency band becomes a certain signal level. Controls the setting values of the variable attenuator 216, the variable gain amplifier 217, or both included in the plurality of frequency converters 214, and the gain control value of the variable gain amplifier 202.

First, the frequency analysis unit 206 performs frequency analysis on the received radio wave output from the variable gain amplifier 202.
The vertical axis and the horizontal axis in FIGS. 13A and 13B are the same as the vertical axis and the horizontal axis in FIGS. 2A and 2B.
FIG. 13A shows received radio waves. FIG. 13B shows an example in which five signals (signal S1 to signal S5) are included in the received radio wave as a result of frequency analysis of the received radio wave.

Also, the received radio wave shown in FIG. 13A is input to a plurality of frequency conversion units 214 assigned to a plurality of frequency bands, and the frequency conversion unit 214 performs frequency conversion on the received radio waves in each frequency band. Output to the variable gain amplifier 202. Therefore, the five signals (signals S1 to S5) obtained as a result of analysis by the frequency analysis unit 206 are assigned to any one of the plurality of frequency conversion units 214.
Here, as shown in FIG. 13B, the signals S1 and S2 are assigned to the frequency converter 1, the signals S3 and S4 are assigned to the frequency converter 2, and the signal S5 is assigned to the frequency converter 3, respectively. Yes.

Further, the gain control unit 208 uses the signals S1, S3, and S5, which are the largest signals among the signals included in the frequency conversion unit 1, the frequency conversion unit 2, and the frequency conversion unit 3, as reference signals. select.
Therefore, the gain control unit 208 detects the signal levels of the reference signals S1, S3, and S5 for a certain period, and is preset with an average value of the signal levels of the reference signal within the detection period. The set value and variable gain amplification of the variable attenuator 216 and / or the variable gain amplifier 217 included in the frequency converter 214 so that the signal level becomes equal to the value of the reference level based on the comparison result. The gain control value of the unit 202 is controlled.
Thereafter, the gain control unit 208 performs gain control similar to that described in the first embodiment on a signal that has reached a certain level.

FIG. 14 is an example of a process flow diagram for the method of controlling the signal level of the received signal with the variable attenuator in FIG.
First, the frequency analysis unit 206 performs frequency analysis on the received radio wave input from the variable gain amplification unit 202 (step S602).

Next, the gain control unit 208 compares the signal level existing in each frequency band for each frequency band divided in advance by the frequency conversion unit 214 with a reference level for equalizing the signal level of each frequency band. Then, the set value of the variable attenuator 216 and / or the variable gain amplifier 217 of each frequency converter 214 of the RF unit 200 and the gain control value of the variable gain amplifier 202 are set so that the signal level becomes the reference level. calculate.
The gain control unit 208 calculates the set values of the variable attenuator 216, the variable gain amplification unit 217, or both, and the gain control value of the variable gain amplification unit 202, respectively, as the variable attenuator 216, the variable gain amplification unit 217, or Both of them are notified or set to the variable gain amplifier 202 (step S604).

  In step S604, the gain control unit 208 sets the signal level existing in each frequency band for each frequency band divided in advance by the frequency conversion unit 214 and the reference level for equalizing the signal level in each frequency band. If the signal level is determined to be equal to the reference level, the process is terminated.

  As described above, when the gain control apparatus according to the second embodiment receives a plurality of radio signals at once, the radio apparatus requires a high dynamic range, but the gain control unit 208 controls the gain. At this time, level adjustment control of the received signal divided for each frequency band is also executed. Thereby, the gain control apparatus of the second embodiment can reduce the load of the dynamic range in the RF unit 200.

<Third Embodiment>
The third embodiment of the present invention will be described below with reference to the drawings. FIG. 15 is a schematic block diagram showing a configuration of a radio apparatus including a gain control apparatus according to the third embodiment of the present invention.

The radio apparatus includes an RF unit 300 including a variable gain amplification unit 302, an AD conversion unit 304, a frequency analysis unit 306, a gain control unit 308, a demodulation processing unit 310, and a radio system database 312. The RF unit 300, variable gain amplification unit 302, AD conversion unit 304, frequency analysis unit 306, gain control unit 308, demodulation processing unit 310, and radio system database 312 shown in FIG. 15 are the same as those shown in FIG. The RF unit 100, the variable gain amplifying unit 102, the AD converting unit 104, the frequency analyzing unit 106, the gain control unit 108, the demodulation processing unit 110, and the radio system database 112 are respectively corresponded.
However, in the first embodiment shown in FIG. 1, the received signal is input from the AD conversion unit 104 to the demodulation processing unit 110, but in FIG. 15, the received signal is input to the AD conversion unit 304, the frequency analysis unit 306, In addition, after passing through the gain control unit 308 in order, it is input to the demodulation processing unit 310.
The description of the same configuration among the corresponding configurations is omitted.

The received signal received by the RF unit 300 is input to the variable gain amplifying unit 302 provided in the RF unit 300, and gain control is performed. The received signal that has been gain-controlled and level-adjusted to a certain magnitude is input to the AD conversion unit 304.
The AD conversion unit 304 converts the reception signal input from the variable gain amplification unit 302 from analog data to digital data, and outputs the digital data to the frequency analysis unit 306.

  The frequency analysis unit 306 performs frequency analysis on the reception signal input from the AD conversion unit 304 to measure the signal level of the signal for each frequency included in the reception signal, and outputs the measurement result to the gain control unit 308. The frequency analysis unit 306 also outputs the input received signal digital data to the gain control unit 308 together.

First, as a first step, the gain control unit 308 performs frequency analysis based on selection conditions registered in the radio system database 312 and set according to the reference signal selection conditions set according to the priority of the radio system. The signal level of the signal for each frequency, which is the measurement result input from the unit 306, is detected, and a signal corresponding to the selection condition is selected as a reference signal based on the detected result.
Further, the gain control unit 308 compares the condition for comparison with the reference signal registered in the wireless system database 312 and the signal level of the selected reference signal, and sets the gain control determined from the comparison result. The value is output to variable gain amplification section 302.
Here, the gain control unit 308 executes gain control similar to that described in the first embodiment by using the gain increase threshold and the gain decrease threshold as conditions for comparison with the reference signal.

Next, as a second step, the gain control unit 308 also executes unnecessary wave removal control on the reception signal obtained in the first step.
The gain control unit 308 is a measurement condition input from the frequency analysis unit 306 based on the selection condition registered in the wireless system database 312 and the reference signal selection condition set according to the priority of the wireless system. The signal level of the signal for each frequency as a result is detected, and a signal corresponding to the selection condition is selected as a reference signal based on the detected result.
Here, the selection condition of the reference signal is all signals of the signals for each frequency, which are the measurement results input from the frequency analysis unit 306, a plurality of high priority signals, or a plurality of arbitrary signals.

Next, the gain control unit 308 compares the condition for comparison with the reference signal registered in the wireless system database 312 and the signal level of the selected reference signal.
Here, the gain control unit 308 uses, as a condition for comparison with the reference signal, a distortion occurrence threshold value for determining whether or not the signal level is a large signal level that causes distortion.

The gain control unit 308 compares the signal levels of a plurality of reference signals with the distortion occurrence threshold, and when there is a reference signal that is determined that the signal level of the reference signal is equal to or higher than the distortion occurrence threshold, the gain control unit 308 generates a harmonic from the reference signal. Generate waves and subharmonics.
Further, the gain control unit 308 removes the generated harmonics and subharmonics from the digital data of the reception signal input from the frequency analysis unit 306 and outputs the digital data to the demodulation processing unit 310.
Demodulation processor 310 demodulates the digital data of the received signal input from gain controller 308.

  When the gain control unit 308 generates harmonics and subharmonics from the reference signal determined to be equal to or greater than the distortion occurrence threshold, the gain control unit 308 generates a phase based on a change in frequency characteristics of the variable gain amplification unit 302 with respect to the reference signal. It is possible to correct and generate harmonics and subharmonics from the phase-corrected signal.

FIG. 16 is an explanatory diagram for explaining the outline of the gain control method according to the third embodiment of the present invention.
For example, when a gain signal according to the first embodiment is executed and a received signal having a high signal level is input to the variable gain amplifier 302, the received signal is distorted and unnecessary waves such as harmonics are generated. May occur. In this case, the gain control unit 308 according to the third embodiment compares the set distortion occurrence threshold value with the signal level of the received signal. If the signal level is equal to or higher than the distortion occurrence threshold value, the received signal at the signal level is distorted. Is determined to have occurred.

The vertical axis and horizontal axis in FIGS. 16A and 16B are the same as the vertical axis and horizontal axis in FIG.
In FIG. 16A, as a result of frequency analysis of the received radio wave by the frequency analysis unit 301, four signals (signal S1 to signal S4) are included in the received radio wave, and the signals S1 and S2 are equal to or greater than the distortion occurrence threshold. An example in which it is determined that

The gain control unit 308 first corrects the phase of the received signal that is equal to or higher than the distortion occurrence threshold based on the change in the frequency characteristic of the variable gain amplification unit 302, and based on the phase-corrected signal, Generate subharmonics.
Then, gain control section 308 removes the generated harmonics / subharmonics from the received signal.
In FIG. 16B, the phase of the signal S1 and the signal S2 determined to be equal to or greater than the distortion occurrence threshold in FIG. 16A is corrected, and unnecessary from the received signal based on the phase corrected signal S1 and signal S2. An example of removing waves is shown.

FIG. 17 is an example of a process flow diagram regarding control related to unnecessary wave removal in the description of FIG. 16.
First, gain control section 308 compares the signal level of each received signal with a distortion occurrence threshold based on the result of frequency analysis of the received signal by frequency analysis section 306 (step S702). Next, when it is determined that the signal level of each received signal is equal to or higher than the distortion occurrence threshold, the gain control unit 308 proceeds to step S706, and when it is determined that the signal level is less than the distortion occurrence threshold, the process is performed. The process ends (step S704).

Subsequently, the gain control unit 308 corrects the phase of the signal determined to be greater than or equal to the distortion occurrence threshold in step S704 based on the characteristics of the variable gain amplification unit 302 (step S706).
Further, the gain control unit 308 generates unnecessary harmonic and subharmonic waves based on the frequency information and signal level information of the phase-corrected signal, and removes them from the received signal (step S708).
The signal level of the target signal is estimated from the magnitudes of harmonics and subharmonics and the control value of gain control.

  In this way, when receiving a plurality of radio signals at once, the gain control apparatus according to the third embodiment predicts signal distortion when performing gain control, and removes unnecessary waves by signal processing. Thereby, the gain control apparatus of the third embodiment can improve the reception characteristics.

  In the embodiment of the present invention, the configuration of the wireless device including the gain control device has been described. However, the gain control device of the present invention is not limited to the configuration of the wireless device, and the gain control device in wired transmission, or The present invention can also be applied to the configuration of a gain control device in an arbitrary device.

  Also, a program for realizing the function of each component constituting the gain control shown in FIGS. 1, 12, and 15 is recorded on a computer-readable recording medium, and the program recorded on the recording medium May be executed by causing the computer system to read and execute. Here, the “computer system” includes an OS and hardware such as peripheral devices.

Further, the “computer system” includes a homepage providing environment (or display environment) if a WWW system is used.
The “computer-readable recording medium” refers to a storage device such as a flexible medium, a magneto-optical disk, a portable medium such as a ROM and a CD-ROM, and a hard disk incorporated in a computer system. Furthermore, the “computer-readable recording medium” dynamically holds a program for a short time like a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line. In this case, a volatile memory in a computer system serving as a server or a client in that case, and a program that holds a program for a certain period of time are also included. The program may be a program for realizing a part of the functions described above, and may be a program capable of realizing the functions described above in combination with a program already recorded in a computer system.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and includes design and the like within a scope not departing from the gist of the present invention.

100, 200, 300 ... RF section, 102, 202, 217, 302 ... variable gain amplification section, 104, 204, 304 ... AD conversion section, 106, 206, 306 ... frequency analysis section, 108, 208, 308 ... gain control , 214 ... Frequency converter, 216 ... Variable attenuator

Claims (11)

A gain control method used in a gain control apparatus for controlling a gain when a signal group in which a plurality of signals having different frequencies are superimposed is collectively amplified,
A variable gain amplification procedure for collectively amplifying the signal group;
A frequency analysis procedure for performing a frequency analysis on the signal output from the variable gain amplification procedure and measuring a signal level for each of the plurality of signals;
Based on a selection method set in advance, one or more of the plurality of signals is selected as a reference signal, and based on the signal level of the selected reference signal, the variable gain amplification procedure And a gain control procedure for controlling the gain.   In the gain control procedure, when controlling the gain of the variable gain amplification procedure, the signal level of the reference signal, a gain increase threshold value for determining a gain control increase control or decrease control set in advance, and 2. The gain control method according to claim 1, wherein the gain is compared with a gain reduction threshold value, and the gain is controlled based on the comparison result.   In the gain control procedure, when one or more of the plurality of signals are selected as the reference signal, a signal having the highest signal level is selected as the reference signal from the plurality of signals. The gain control method according to claim 1 or 2, wherein   In the gain control procedure, when one or more of the plurality of signals are selected as the reference signal, a signal having the lowest signal level is selected as the reference signal from the plurality of signals. The gain control method according to claim 1 or 2, wherein   In the gain control procedure, the signal level of the plurality of signals is compared with the gain increase threshold and the gain decrease threshold, and gain increase control or decrease control and gain control are determined for each of the plurality of signals based on the comparison result. The gain control method according to claim 1 or 2, wherein a value is calculated and the most control among the results of the comparison is selected.   In the gain control procedure, when selecting one or more of the plurality of signals as the reference signal, based on a priority set in advance for each signal of the superimposed signal group, The gain control method according to claim 1 or 2, wherein a signal having a high priority is selected as the reference signal from a plurality of signals. A plurality of frequency conversion procedures for performing frequency conversion for each frequency band of the superimposed signal group in the previous stage of signal input of the variable gain amplification procedure,
The frequency conversion procedure includes at least a variable attenuator procedure or a second variable gain amplification procedure,
In the variable attenuator procedure, adjust the signal level of the received signal for each frequency band assigned to the frequency conversion procedure,
In the second variable gain amplification procedure, the signal level of the received signal for each frequency band assigned to the frequency conversion procedure is collectively amplified,
In the gain control procedure, the reference signal selected for each frequency band of the signal output of the frequency conversion procedure is compared with a predetermined reference level so that the reference signal becomes equal to the reference level. The control value of the variable attenuator procedure or the second variable gain amplification procedure and the control value of the variable gain amplification procedure are calculated, and the variable attenuator procedure or the second variable gain is calculated based on the calculated control value. The gain control method according to claim 1, wherein an amplification procedure and the variable gain amplification procedure are controlled. An AD conversion procedure for converting the signal output of the variable gain amplification procedure from an analog signal to a digital signal;
The frequency analysis procedure performs frequency analysis on the signal output from the AD conversion procedure, measures the signal level for each of the plurality of signals,
The gain control procedure compares the previous signal level for each of the plurality of signals with a preset distortion occurrence threshold, and detects a signal with the signal level equal to or higher than the distortion occurrence threshold.
Generate an unnecessary wave from the frequency information of the signal, or generate the unnecessary wave based on a signal obtained by correcting the phase of the signal based on the frequency characteristics of the variable gain amplification procedure,
The gain control method according to claim 1, wherein the unnecessary wave is removed from the signal output. A gain control device for controlling a gain when collectively amplifying a signal group in which a plurality of signals having different frequencies are superimposed,
A variable gain amplifying unit for collectively amplifying the signal group;
A frequency analysis unit that performs frequency analysis on the signal output from the variable gain amplification unit and measures a signal level for each of the plurality of signals;
Based on a selection method set in advance, one or more signals are selected as a reference signal from the plurality of signals, and based on the signal level of the selected reference signal, the variable gain amplification unit A gain control apparatus comprising: a gain control unit that controls the gain. A plurality of frequency conversion units that perform frequency conversion of the superimposed signal group for each frequency band in a previous stage of signal input of the variable gain amplification unit,
The frequency conversion unit includes at least a variable attenuator unit or a second variable gain amplification unit,
The variable attenuator unit adjusts the signal level of the received signal for each frequency band assigned to the frequency converter,
The second variable gain amplifying unit collectively amplifies the signal level of the received signal for each frequency band assigned to the frequency converting unit,
The gain control unit compares the reference signal selected for each frequency band of the signal output of the frequency conversion unit with a predetermined reference level so that the reference signal becomes equal to the reference level. Calculating a control value of the variable attenuator unit or the second variable gain amplifying unit and a control value of the variable gain amplifying unit, and based on the calculated control value, the variable attenuator unit or the second variable gain unit The gain control apparatus according to claim 9, wherein an amplifying unit and the variable gain amplifying unit are controlled. An AD converter that converts the signal output of the variable gain amplifier from an analog signal to a digital signal;
The frequency analysis unit performs frequency analysis on the signal output from the AD conversion unit, measures the signal level for each of the plurality of signals,
The gain control unit compares the previous signal level for each of the plurality of signals with a preset distortion occurrence threshold, and detects a signal with the signal level equal to or higher than the distortion occurrence threshold,
Generate an unnecessary wave from the frequency information of the signal, or generate the unnecessary wave based on a signal obtained by correcting the phase of the signal based on the frequency characteristics of the variable gain amplifier,
The gain control apparatus according to claim 9, wherein the unnecessary wave is removed from the signal output.

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