JP4166064B2 - Wireless device, IQ signal adjustment method, and IQ signal adjustment program - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a radio apparatus, an IQ signal adjustment method, and an IQ signal adjustment program, and in particular, a radio apparatus having a transmission / reception function such as a radio base apparatus in a mobile communication system, and IQ signal adjustment in such a radio apparatus. The present invention relates to a method and an adjustment program.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, in a mobile communication system such as a PHS (Personal Handyphone System), for example, a known π / 4 shift is performed between a mobile terminal device (hereinafter referred to as a terminal) and a radio base device (hereinafter referred to as a base station). QPSK (Quadrature Phase Shift
Wireless communication has been performed by a modulation method such as (Keying).
[0003]
In a radio transmission apparatus that employs such a modulation method, modulation processing is performed by separating into an in-phase signal (hereinafter referred to as I signal) and a quadrature signal (hereinafter referred to as Q signal). It is.
[0004]
In such a wireless transmission device, in order to obtain a transmission signal with good modulation accuracy, it is desirable that the I signal and the Q signal (hereinafter, both are collectively referred to as an IQ signal) be balanced. Specifically, it is desirable that the amplitude and voltage level are balanced between IQ signals.
[0005]
For this reason, it is necessary to match the amplitude and voltage level of each IQ signal to values within a range set in advance at the time of design in the wireless transmission device.
[0006]
For example, in a conventional base station, such IQ signal adjustment is basically performed before shipment as part of the production process in a factory.
[0007]
On the other hand, after installing a base station on the site, the magnitude of the IQ signal changes due to deterioration of parts or sudden failure due to aging and environmental changes, and there is a deviation in voltage level as a whole (offset). There is a case.
[0008]
Thus, when the IQ signal adjustment deviates from the original proper value after shipment, the installed base station must be removed and sent back to the factory for readjustment.
[0009]
FIG. 5 is a block diagram showing a circuit portion of a transmission system extracted from a conventional base station. Referring to FIG. 5, a digital IQ signal is given to a transmission system circuit 2 in the base station 1 from a signal processing unit (not shown).
[0010]
More specifically, the digital I signal is converted into an analog signal by the D / A converter 3a, and then supplied to the offset adjuster 4a that can manually adjust the voltage level up and down.
[0011]
The analog I signal level-adjusted by the offset adjuster 4a is supplied to the variable gain amplifier 5a that can manually adjust the amplification factor. The output of the variable gain amplifier 5a is further amplified by the amplifier 6a and then given to one input of the mixer 7a. An oscillation signal having an intermediate frequency (IF) is given to the other input of the mixer 7a from an oscillation circuit (not shown) via the distributor 8.
[0012]
The intermediate frequency I signal output from the mixer 7 a is applied to one input of the adder 9.
[0013]
On the other hand, the digital Q signal is converted into an analog signal by the D / A converter 3b, and then supplied to the offset adjuster 4b which can manually adjust the voltage level up and down.
[0014]
The analog Q signal whose level is adjusted by the offset adjuster 4b is supplied to the variable gain amplifier 5b whose gain can be adjusted manually. The output of the variable gain amplifier 5b is further amplified by the amplifier 6b and then applied to one input of the mixer 7b. The other input of the mixer 7b is supplied with an oscillation signal having an intermediate frequency (IF) from an oscillation circuit (not shown) through the distributor 8.
[0015]
The intermediate frequency Q signal output from the mixer 7 b is applied to the other input of the adder 9.
[0016]
The modulation signal added by the adder 9 is given to one input of the mixer 10. A radio frequency (RF) oscillation signal is given to the other input of the mixer 10 from an oscillation circuit (not shown).
[0017]
The radio frequency transmission signal output from the mixer 10 is further amplified by the amplifier 11 and then output from the transmission system circuit 2. The transmission signal output from the transmission system circuit 2 is normally transmitted by an antenna (not shown).
[0018]
Here, as described above, the adjustment of the IQ signal in the transmission system circuit 2 in the base station 1 has been manually performed in a process before factory shipment.
[0019]
More specifically, referring to FIG. 5, the offset (offset) of the voltage level of the IQ signal is adjusted while the operator monitors the output of the measuring instrument 12 connected to the output of the transmission system circuit 2. By manually adjusting the variable resistors of the devices 4a and 4b, the values were adjusted within a preset range.
[0020]
Further, the change in the amplitude of the IQ signal is adjusted by manually adjusting the amplification factors of the variable gain amplifiers 5a and 5b while the operator monitors the output of the measuring instrument 12 connected to the output of the transmission system circuit 2, respectively. The value was adjusted within a preset range.
[0021]
In addition, although the prior art about this invention was demonstrated based on the general technical information which the applicant acquired, the information which should be disclosed as prior art document information before filing in the range which an applicant memorize | stores The applicant does not have
[0022]
[Problems to be solved by the invention]
As described above, the IQ signal of the base station is manually adjusted in the factory while watching the measurement result of the measuring instrument before shipment. Such adjustment of the IQ signal is a very delicate operation, requiring skill of the operator, and it takes time and effort for the actual adjustment operation. Further, the adjustment is performed manually while looking at the measuring instrument of the operator, and the adjustment accuracy is not always sufficient.
[0023]
In addition, after the base station is installed, if the IQ signal needs to be readjusted due to secular change or failure, the base station is sent back to the factory, and manual re-operation using the above-described measuring instrument by the operator is performed. There is a need to make adjustments, and the work becomes very complicated, and the base station cannot be used during that time.
[0024]
Therefore, the present invention provides a radio apparatus, an IQ signal adjustment method, and an IQ signal adjustment program capable of automatically adjusting a high-precision IQ signal without using manual adjustment using a measuring instrument. It is.
[0025]
Another object of the present invention is to provide a radio apparatus, an IQ signal adjustment method, and an IQ signal adjustment program capable of automatically adjusting an IQ signal at the place where the apparatus is installed without being removed and sent back to the factory. It is.
[0026]
[Means for Solving the Problems]
According to one aspect of the present invention, a wireless device that transmits and receives a signal via an antenna includes a transmission system circuit, a reception system circuit, a switch circuit, and a control unit. The transmission system circuit performs a predetermined process on the transmission signal composed of the IQ signal and transmits it from the antenna. The reception system circuit demodulates the signal received by the antenna. The switch circuit gives a transmission signal subjected to predetermined processing in the transmission system circuit to the reception system circuit when adjusting the IQ signal. The transmission system circuit includes an adjustment circuit that changes each predetermined characteristic of the IQ signal, and the reception system circuit detects a deviation from an appropriate value of each predetermined characteristic of the IQ signal of the transmission signal received from the transmission system circuit. A filter circuit for detection is included. The control unit controls the adjustment circuit according to the detection output of the filter circuit so that the predetermined characteristic of the IQ signal becomes an appropriate value.
[0027]
Preferably, the IQ signal characteristics are amplitude and voltage level. The filter circuit includes a first filter that extracts a signal component that represents a deviation from an appropriate value of amplitude, and a second filter that extracts a signal component that represents a deviation from an appropriate value of the voltage level. The control unit controls the adjustment circuit according to the output levels of the first and second filters.
[0028]
Preferably, the control unit specifies the amplitude of the IQ signal that minimizes the output level of the first filter, specifies the voltage level of the IQ signal that minimizes the output level of the second filter, and determines the amplitude of the IQ signal. The control circuit controls the adjustment circuit so that the voltage level becomes the specified amplitude and voltage level.
[0029]
Preferably, the adjustment circuit changes a predetermined characteristic of each of the digital IQ signals.
[0030]
Preferably, the adjustment circuit changes a predetermined characteristic of each of the analog IQ signals.
[0041]
Therefore, according to the present invention, the IQ signal characteristic in the transmission unit of the wireless device can be automatically adjusted to an optimum value, not manually using a measuring instrument. The efficiency and accuracy of the adjustment can be improved.
[0042]
Furthermore, according to the present invention, adjustment of IQ signal characteristics in the transmission unit of the wireless device can be automatically performed periodically or in response to an instruction from the outside, so that it remains installed in the field without being sent back to the factory. Adjustment can be performed in the state of.
[0043]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.
[0044]
[Embodiment 1]
FIG. 1 is a functional block diagram of a base station as a radio apparatus according to Embodiment 1 of the present invention. Referring to FIG. 1, the base station 1 roughly includes a transmission system circuit 20, a switch circuit 30, an antenna 40, a reception system circuit 50, a line interface 60, a signal processing unit 70, and a local signal generation. Device 80, distributors 81 and 82, and control unit 100.
[0045]
More specifically, at the time of transmission from the base station 1, a transmission signal transmitted from the center (not shown) to the base station 1 via the I ′ line is given to the signal processing unit 70 via the line interface 60.
[0046]
The signal processing unit 70 performs modulation processing, for example, π / 4 shift QPSK modulation, on the transmission signal as part of the function of the transmission system circuit 20. Therefore, in the signal processing unit 70, the transmission signal is separated into IQ signals, subjected to predetermined signal processing, and further subjected to amplitude adjustment and offset adjustment according to the present invention.
[0047]
More specifically, in the signal processing unit 70, the digital I signal is supplied to the amplitude adjustment circuit 71 a that can automatically adjust the magnitude of the amplitude according to the control signal supplied from the control unit 100.
[0048]
The digital I signal whose amplitude is adjusted by the amplitude adjusting circuit 71 a is supplied to an offset adjusting circuit 72 a that can automatically adjust the voltage level up and down in accordance with a control signal supplied from the control unit 100.
[0049]
The digital I signal level-adjusted by the offset adjustment circuit 72 a is output from the signal processing circuit 70 and given to the D / A converter 21 a of the transmission system circuit 20. The digital I signal is converted into an analog I signal by the D / A converter 21a.
[0050]
The analog I signal is further amplified by the amplifier 22a and then applied to one input of the mixer 23a. An oscillation signal having an intermediate frequency (IF) is supplied to the other input of the mixer 23 a from the local signal generation circuit 80 via the distributors 82 and 24.
[0051]
The intermediate frequency I signal output from the mixer 23 a is applied to one input of the adder 25.
[0052]
On the other hand, in the signal processing unit 70, the digital Q signal is supplied to an amplitude adjustment circuit 71 b that can automatically adjust the magnitude of the amplitude in accordance with a control signal supplied from the control unit 100.
[0053]
The digital Q signal whose amplitude is adjusted by the amplitude adjustment circuit 71b is supplied to an offset adjustment circuit 72b that can automatically adjust the voltage level up and down in accordance with a control signal supplied from the control unit 100.
[0054]
The digital Q signal whose level is adjusted by the offset adjustment circuit 72 b is output from the signal processing circuit 70 and is supplied to the D / A converter 21 b of the transmission system circuit 20. The digital Q signal is converted into an analog Q signal by the D / A converter 21b.
[0055]
The analog Q signal is further amplified by the amplifier 22b and then applied to one input of the mixer 23b. An oscillation signal having an intermediate frequency (IF) is supplied to the other input of the mixer 23b from the local signal generation circuit 80 via the distributors 82 and 24.
[0056]
The intermediate frequency Q signal output from the mixer 23 b is supplied to the other input of the adder 25.
[0057]
The modulation signal added by the adder 25 is given to one input of the mixer 26. A radio frequency (RF) oscillation signal is applied to the other input of the mixer 26 from the local signal generation circuit 80 via the distributor 81.
[0058]
The radio frequency transmission signal output from the mixer 26 is further amplified by the amplifier 27, and is then supplied from the transmission system circuit 20 to the antenna 40 via the switch circuit 30 and transmitted. More specifically, at the time of transmission, the switch 31 of the switch circuit 30 is switched to connect the output of the transmission system circuit 20 to the antenna 40 by a switching control signal given from the control unit 100.
[0059]
The switch circuit 30 includes a switch 32 for directly giving (looping back) the output of the transmission system circuit 20 to the input of the reception system circuit 50. It is assumed that the loopback switch 32 is opened by a control signal.
[0060]
On the other hand, at the time of reception by the base station 1, the reception signal from the terminal received by the antenna 40 is given to the input of the reception system circuit 50 via the switch circuit 30. At this time, the switch 31 of the switch circuit 30 is switched to connect the output of the antenna 40 to the input of the reception system circuit 50 in accordance with a switching control signal given from the control unit 100.
[0061]
It is assumed that the loopback switch 32 is opened by the switching control signal from the control unit 100 even at the time of the above reception.
[0062]
A reception signal given from the antenna 40 to the reception system circuit 50 is amplified by the amplifier 51 and then given to one input of the mixer 52. The other input of the mixer 52 is supplied with a radio frequency (RF) oscillation signal from the local signal generating circuit 80 via the distributor 81.
[0063]
The radio frequency reception signal output from the mixer 52 is further amplified by the amplifier 53 and then given to one input of the mixer 55 and one terminal of the switch 56 by the distributor 54.
[0064]
The other input of the mixer 55 is supplied with an oscillation signal having an intermediate frequency (IF) from the local signal generation circuit 80 via the distributor 82.
[0065]
The intermediate frequency reception signal output from the mixer 55 is supplied to the signal processing unit 70. In the signal processing unit 70, predetermined demodulation processing is performed on the received signal.
[0066]
On the other hand, the received signal given from the distributor 54 to the switch 56 is a well-known signal indicating the power level of the received signal via the switch 56 that is controlled to be switched by the switching control signal from the control unit 100 during normal reception operation. A level measurement unit 59 is provided via a switch 58 which is given to a wideband filter 57a for measuring an RSSI (Received Signal Strength Indicator) which is an index, and whose filter output is switched and controlled by a switching control signal from the control unit 100. Given to.
[0067]
The level measurement unit 59 measures the RSSI that is the reception power level based on the output of the filter 57 a and supplies the RSSI to the signal processing unit 70. The measured received power level RSSI is used for various signal processing in the signal processing unit.
[0068]
An operation of automatically adjusting the amplitude and offset of the IQ signal in base station 1 of the first embodiment as described above will be described.
[0069]
In this IQ signal adjustment mode, on the basis of the switching control signal from the control unit 100, the switch 31 of the switch circuit 30 does not connect either the transmission system circuit 20 or the reception system circuit 50 to the antenna 40. Then, the loopback switch 32 is closed so that the output of the transmission system circuit 20 is directly applied to the input of the reception system circuit 50.
[0070]
Then, the switch 56 in the reception system circuit 50 gives the reception signal from the distributor 54 to the narrowband filter 57c for amplitude adjustment by the switching control signal from the control unit 100. The filter output is given to the level measuring unit 59 through a switch 58 that is switch-controlled by a switch control signal from the control unit 100.
[0071]
The level of the amplitude adjusting filter 57c measured by the level measuring unit 59 is given to the control unit 100 via the signal processing unit 70, and the control unit 100 in the signal processing unit 70 based on the measured level. A control signal for the amplitude adjusting circuits 71a and 71b is generated to adjust the amplitude of the digital IQ signal. A specific method of adjustment will be described later.
[0072]
Next, the switch 56 in the reception system circuit 50 supplies the received signal from the distributor 54 to the narrow band filter 57b for offset adjustment by the switching control signal from the control unit 100. The filter output is given to the level measuring unit 59 through a switch 58 that is switch-controlled by a switch control signal from the control unit 100.
[0073]
The level of the offset adjustment filter 57b measured by the level measuring unit 59 is given to the control unit 100 via the signal processing unit 70, and the control unit 100 in the signal processing unit 70 based on the measured level. A control signal for the offset adjustment circuits 72a and 72b is generated to adjust the offset of the digital IQ signal. A specific method of adjustment will be described later.
[0074]
FIG. 2 is a waveform diagram for explaining the operation principle of the present invention. Next, the principle of adjusting the amplitude and offset of the IQ signal according to the present invention will be described with reference to FIG.
[0075]
FIG. 2 is a spectrum diagram obtained when a 00 pattern signal is transmitted under the condition of 192 K symbols / second and frequency f using the π / 4 shift QPSK modulation method.
[0076]
Here, when the spectrum at the center of the frequency f is minimum, the offset of the IQ signal is optimal, and when the spectrum on the left side of the frequency f−24 KHz is minimum, the amplitude of the IQ signal is optimal.
[0077]
Therefore, it is necessary to extract signal components in the frequency band of these spectrums and measure their levels. Conventionally, a filter for reception power level RSSI measurement (filter 57a in FIG. 1) provided in the reception system circuit. Is too wide. For this reason, a narrowband filter 57b dedicated to offset adjustment for extracting the signal component of the spectrum of frequency f and a narrowband filter 57c dedicated to amplitude adjustment for extracting the signal component of the spectrum of frequency f-24KHz are provided. It is.
[0078]
In the present invention, the amplitude and offset of the IQ signal are adjusted so that the output levels of these narrow band filters are minimized.
[0079]
The configuration of the functional block diagram of the base station shown in FIG. 1 is actually executed by software according to a flowchart shown in FIG. 3 by a digital signal processor (DSP) (not shown). The DSP reads a program including each step of the flowchart shown in FIG. 3 from a memory (not shown) and executes the program. This program can be installed in the base station from an external center via a line.
[0080]
The IQ signal adjustment operation of the base station according to Embodiment 1 of the present invention will be described below with reference to FIG.
[0081]
First, in step S1, the IQ signal adjustment operation is automatically started periodically (for example, once a week, once a month, etc.) by an interruption by a timer, or an instruction from an external center (for example, When the base station is suspected of performance degradation, the IQ signal adjustment operation is started.
[0082]
Next, in step S2, while changing the amplitude of each IQ signal transmitted in the signal processing unit 70, the level measuring unit 59 of the reception system circuit 50 acquires the output level of the amplitude adjusting filter 57c, and the result is obtained. Store in a memory (not shown).
[0083]
Next, in step S3, while changing the offset of each IQ signal transmitted in the signal processing unit 70, the level measurement unit 59 of the reception system circuit 50 acquires the output level of the offset adjustment filter 57b, and the result is obtained. Store in a memory (not shown).
[0084]
Next, in step S4, the minimum value of each output level of the filters 57c and 57b acquired in steps S2 and 3 is searched.
[0085]
Next, in step S5, the amplitude adjustment circuits 71a and 71b are adjusted so that the output level of the amplitude adjustment filter 57c searched in step S4 becomes the amplitude of the IQ signal that becomes the minimum value.
[0086]
Next, in step S6, the offset adjustment circuits 72a and 72b are adjusted so that the output level of the offset adjustment filter 57b searched in step S4 becomes the offset of the IQ signal that becomes the minimum value.
[0087]
As a result, the amplitude and offset of the IQ signal are adjusted to match the optimum values.
[0088]
As described above, according to the first embodiment of the present invention, the amplitude and offset of the IQ signal in the transmission system circuit of the base station are automatically adjusted to optimum values instead of manual adjustment using a measuring instrument. Therefore, it is possible to improve the efficiency and accuracy of adjusting the IQ signal in the production process of the factory.
[0089]
Further, according to the first embodiment of the present invention, the adjustment of the amplitude and offset of the IQ signal in the transmission system circuit of the base station can be automatically performed periodically or in response to an instruction from the center. Adjustments can be made without removing the station and sending it back to the factory.
[0090]
[Embodiment 2]
FIG. 4 is a functional block diagram of a base station as a radio apparatus according to Embodiment 2 of the present invention. The base station according to Embodiment 2 shown in FIG. 4 is different from the base station according to Embodiment 1 shown in FIG. 1 in the following points, and description of common parts will not be repeated.
[0091]
That is, in the base station of the first embodiment of FIG. 1, the amplitude and offset of the IQ signal are adjusted by digital signal processing in the signal processing unit 70, but in the base station of the second embodiment of FIG. The IQ signals after being converted into analog signals by the D / A converters 91a and 91b in the transmission system circuit unit 90 are offset by the offset adjusters 92a and 92b that are automatically controlled by the control signal from the control unit 100. Adjustment is performed, and amplitude adjustment is performed by variable gain amplifiers 93a and 93b that are automatically controlled by a control signal from the control unit 100.
[0092]
The control signals for controlling the offset adjusters 92a and 92b and the variable gain amplifiers 93a and 93b are the output level and amplitude adjustment of the filter 57b for offset adjustment measured by the level measuring unit 59, as in the first embodiment. This is a signal for adjusting the offset and the amplitude of the IQ signal so that the output level of the filter 57c for use is minimized.
[0093]
Since the offset and amplitude adjustment procedures are the same as those in the flowchart of the first embodiment shown in FIG. 3, description thereof will not be repeated here.
[0094]
The amplifiers 94a and 94b, the mixers 95a and 95b, the distributor 96, the adder 97, the mixer 98, and the amplifier 99 constituting the transmission system circuit 90 are the amplifiers of the transmission system circuit 20 according to the first embodiment shown in FIG. 22a, 22b, mixers 23a, 23b, distributor 24, adder 25, mixer 26, and amplifier 27, the description thereof will not be repeated here.
[0095]
As described above, according to the second embodiment of the present invention, the amplitude and offset of the IQ signal in the transmission system circuit of the base station are automatically adjusted to optimum values instead of manual adjustment using a measuring instrument. Therefore, it is possible to improve the efficiency and accuracy of adjusting the IQ signal in the production process of the factory.
[0096]
Furthermore, according to the second embodiment of the present invention, the adjustment of the amplitude and offset of the IQ signal in the transmission system circuit of the base station can be automatically performed periodically or in response to an instruction from the center. Adjustments can be made without removing the station and sending it back to the factory.
[0097]
In the first and second embodiments described above, the base station has been described as an example of the radio apparatus. However, the IQ signal adjustment method according to the present invention is not limited to the base station, and includes a transmission system circuit and a reception system circuit. Any wireless device can be applied as long as the wireless device is provided.
[0098]
The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.
[0099]
【The invention's effect】
As described above, according to the present invention, the characteristic of the IQ signal in the transmission unit of the wireless device can be automatically adjusted to an optimal value instead of manual adjustment using a measuring instrument. It is possible to increase the efficiency and accuracy of IQ signal adjustment in the process.
[0100]
Furthermore, according to the present invention, the IQ signal characteristics can be automatically adjusted at the transmitter of the wireless device periodically or in response to an instruction from the outside. Adjustments can be made while installed.
[Brief description of the drawings]
FIG. 1 is a functional block diagram of a base station according to Embodiment 1 of the present invention.
FIG. 2 is a waveform diagram illustrating the operating principle of the present invention.
FIG. 3 is a flowchart showing an IQ signal adjustment method according to Embodiment 1 of the present invention;
FIG. 4 is a functional block diagram of a base station according to Embodiment 2 of the present invention.
FIG. 5 is a block diagram of a transmission unit of a conventional base station.
[Explanation of symbols]
1 Base station, 2, 20, 90 Transmission system circuit, 3a, 3b, 21a, 21b, 91a, 91b D / A converter, 4a, 4b, 92a, 92b Offset adjuster, 5a, 5b, 93a, 93b Variable gain amplifier 6a, 6b, 11, 22a, 22b, 27, 51, 53, 94a, 94b, 99 amplifier, 7a, 7b, 10, 55, 95a, 95b, 98 mixer, 8, 24, 54, 81, 82, 96 distributor, 9, 25, 97 adder, 12 measuring instrument, 30 switch circuit, 31, 32, 56, 58 switch, 40 antenna, 50 reception system circuit, 57a RSSI measurement filter, 57b offset adjustment filter, 57c amplitude Adjustment filter, 59 level measurement unit, 60 line interface, 70, 110 signal processing unit, 71a, 71b amplitude adjustment circuit, 2a, 72b offset adjusting circuit, 80 a local signal oscillator, 100 controller.

Claims (5)

A wireless device that transmits and receives signals via an antenna,
A transmission system circuit that performs predetermined processing on a transmission signal composed of an IQ signal and transmits the signal from the antenna;
A receiving circuit for demodulating a signal received by the antenna;
A switch circuit that provides the reception system circuit with the transmission signal subjected to the predetermined processing in the transmission system circuit when adjusting the IQ signal;
The transmission system circuit
An adjustment circuit for changing a predetermined characteristic of each of the IQ signals;
The receiving circuit is
A filter circuit for detecting a deviation of the transmission signal received from the transmission system circuit from an appropriate value of each of the predetermined characteristics of the IQ signal;
A radio apparatus further comprising: a control unit that controls the adjustment circuit so that the predetermined characteristic of the IQ signal becomes the appropriate value in accordance with a detection output of the filter circuit. The characteristics of the IQ signal are amplitude and voltage level;
The filter circuit is
A first filter for extracting a signal component representing a deviation from an appropriate value of the amplitude;
A second filter for extracting a signal component representing a deviation from an appropriate value of the voltage level,
The radio apparatus according to claim 1, wherein the control unit controls the adjustment circuit according to output levels of the first and second filters. The controller is
Identifying the amplitude of the IQ signal that minimizes the output level of the first filter;
Identifying the voltage level of the IQ signal that minimizes the output level of the second filter;
The radio apparatus according to claim 2, wherein the adjustment circuit is controlled so that an amplitude and a voltage level of the IQ signal become the specified amplitude and voltage level.   The radio apparatus according to claim 1, wherein the adjustment circuit changes the predetermined characteristic of each of the digital IQ signals.   The radio apparatus according to claim 1, wherein the adjustment circuit changes the predetermined characteristic of each of the analog IQ signals.

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