JP2002290376A - Reference signal clip control system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize stable automatic gain control independently of the steepness of envelope fluctuations of a processed signal. SOLUTION: An RF section 2 receiving a base band signal outputted from a CONT section 1 up-converts the frequency of the base band into a transmission frequency, a detection circuit section 4 applies envelope detection to the transmission signal, an analog/digital converter 8 applies discrete data processing to the resulting signal and gives the result to a comparison calculation circuit 7. Furthermore, a clip processing section 5 estimates detection deterioration from the base band signal obtained from the CONT section 1 and caused by a time constant in a detection circuit section 4 to process the data. The comparison calculation circuit 7 compares data from the clip processing section 5 with data from the detection circuit section 4, and adjusts an ATT amount in the RF section 2 depending on the difference to stabilize the output level.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reference signal clip control system, and more particularly to a method of using a reference signal in consideration of a deterioration of a detection voltage generated when a modulated wave having a large amplitude fluctuation such as CDMA is detected. By clipping the data with sharp fluctuations to the baseband signal, the difference generated by the time constant at the time of detection is absorbed, and stable automatic gain control independent of the sharpness of the envelope fluctuation of the signal to be handled is achieved. The present invention relates to a reference signal clip control method that can be performed.

[0002]

2. Description of the Related Art Conventionally, in a communication apparatus, in order to obtain stable transmission power, gain is obtained by comparing reference data using a baseband signal generated by a transmission / reception control unit (CONT unit) with detection data of transmission output. A method called automatic gain control for adjustment is used.

Normally, a detection circuit used for forming detection data includes a diode, a capacitor C, and a resistor R.
Has been used to detect the envelope of an input signal by a detection method using the following method.

However, when detecting the envelope of a modulated wave having an amplitude fluctuation with respect to an unmodulated wave having a constant power, if the gradient of the charge / discharge change determined by the time constant CR is not appropriately given, the input signal Power may not be efficiently converted to a voltage component. Therefore, in order to detect correctly, it is necessary to appropriately set a time constant determined by CR.

[0005]

However, in a system in which the same frequency is used by a plurality of users, such as CDMA for mobile communication, the power is controlled by performing power control on a signal used according to the position of the user. Is amplified and a plurality of signals are multiplexed in order to increase the efficiency of frequency use, resulting in a waveform having a large power level and a large fluctuation.

For this reason, it is difficult to find an appropriate time constant CR corresponding to all modulated wave output patterns.
At present, stable detection cannot be performed.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional circumstances, and has been made to solve the above-mentioned problems inherent in the conventional technology. Therefore, an object of the present invention is to provide a modulated wave having a large amplitude fluctuation such as CDMA. By taking into account the degradation of the detection voltage that occurs during detection, the baseband signal used as reference data is clipped for data with sharp fluctuations, and the difference generated by the time constant at the time of detection is absorbed. , A new reference signal clip that realizes stable automatic gain control that does not depend on the sharpness of the envelope fluctuation of the signal to be handled in consideration of the variation in the detection voltage due to the type of signal input to the detection circuit It is to provide a control method.

[0008]

In order to achieve the above object, a reference signal clip control system according to the present invention comprises:
In a mobile communication system using A, transmission control means for outputting a baseband signal, radio frequency means for up-converting to a frequency for transmitting the baseband signal output from the transmission control means, Detection circuit means for performing envelope detection on the converted signal, A / D conversion means for converting the detection output detected by the detection circuit means into discrete data, and the baseband signal output from the transmission control means. Clip processing means for estimating detection deterioration caused by a time constant in the detection circuit means and processing data by clipping steeply fluctuating data; and data output from the clip processing means and data from the detection circuit means. And compares the data with the data in the radio frequency means.
Gain fluctuation calculating circuit means for adjusting the amount of T to absorb the difference from the true value caused by the time constant at the time of detection and stabilizing the output level.

The radio frequency means includes a first mixer for mixing and outputting a baseband signal output from the transmission control means, and a band for removing unnecessary waves outside a required band from the output of the first mixer. A pass filter, a first amplifier for amplifying the output of the filter, a second mixer for mixing and outputting the output of the first amplifier, and a variable ATT for variably attenuating the output of the second mixer. , The variable A
A second amplifier for amplifying the output of the TT.

The clip processing means includes a first differentiator for differentiating a baseband signal from the transmission / reception control means, a second differentiator for differentiating an output signal from the A / D converter, A threshold calculator that receives output signals from the first and second differentiators and generates a threshold, and a comparison processor that compares an output of the first differentiator with threshold data output from the threshold calculator. And processing the baseband signal based on discrete data of detection information from the detection circuit means.

The threshold calculator has a threshold data table stored in the threshold calculator with respect to the threshold data calculated by the threshold calculator, and the comparison processor has a threshold data table based on the threshold data in the threshold data table. A comparison determination is performed on the inclination information obtained from the first differentiator; if the inclination information exceeds the threshold, the reference data is clipped; Is sent.

The first and second differentiators are provided with a delay function, and the threshold calculator is supplied with data from the first and second differentiators in the same phase to form the threshold data table. ing.

In calculating the threshold data by the threshold calculator, the characteristics of the detection circuit means are grasped in advance,
It is necessary to obtain discrete data of detection capability information.

As a first method for obtaining the discrete data,
The transmission / reception control means outputs several types of CDMA data having different numbers of multiplexes and codes as sample data, and the threshold calculator calculates the inclination information of the discrete data and the inclination of the discrete data of the detection capability information when the transmission / reception control signal is output. The information is compared with the information, and a threshold data table is created under each condition.

As a second method for obtaining the discrete data,
By measuring the input / output characteristics of the detection circuit means in advance, the detection capability as the detection circuit means is converted into a mathematical expression and stored in the threshold calculator.

The gain variation calculation circuit means includes: the A / D conversion means having an output from the detection circuit means as an input;
A comparator for comparing the output from the A / D conversion unit with the output from the clip processing unit, and a control signal for controlling the variable ATT in the radio frequency unit by inputting the output of the comparator. A comparison calculation circuit comprising a variable ATT controller, and a gain difference obtained by comparing a baseband signal processed by the clipping means with a detection signal of a coupling signal to an output of the radio frequency means. Based on the above, the variable ATT in the radio frequency means is controlled in order to stabilize the level of the output signal.

The comparator in the comparison calculation circuit includes a first delay circuit, a second delay circuit, a first averaging circuit receiving an output of the first delay circuit as an input, and a second delay circuit. Averaging circuit that receives the output of the second averaging circuit, an adder that adds the outputs of the first and second averaging circuits, a comparison value conversion table, an output of the adder, and the comparison value conversion table. And a multiplier for multiplying the output of the clipping processing unit by the A / D conversion of the output of the detection circuit with the discrete signal, and comparing the difference with the variable ATT control in the comparison calculation circuit. It has a function to convert the information into the information necessary for the unit.

The first and second delay circuits and the first and second delay circuits
The second averaging circuit is a circuit that absorbs a change in a time difference and an amplitude difference of a signal input to the comparator caused by a propagation delay or a calculation processing time.

[0019]

Next, a preferred embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing one embodiment of the present invention.

[0021]

FIG. 1 is a block diagram showing an embodiment of the present invention; a transmission control unit 1 (hereinafter abbreviated as a CONT unit 1) and a radio frequency unit 2 (hereinafter abbreviated as an RF unit 2); , A coupler 3, a detection circuit 4, a clip processing unit 5, and a gain variation calculation circuit 6, which are roughly divided into six blocks.
And a D converter 8.

In FIG. 1, the baseband signal output from the CONT unit 1 is up-converted to the frequency transmitted by the RF unit 2, and after the envelope detection by the detection circuit unit 4, the A / D converter 8 discretizes it. Data,
It is input to the comparison calculation circuit 7.

The clip processing unit 5 estimates the detection deterioration caused by the time constant of the detection circuit unit 4 for the baseband signal obtained from the CONT unit 1, and processes the data. The comparison calculation circuit 7 compares the data from the clip processing unit 5 with the data from the detection circuit unit 4, adjusts the ATT amount in the RF unit 2 according to the difference, and stabilizes the output level.

The above control absorbs the difference from the true value generated by the time constant at the time of detection, and enables stable automatic gain control independent of the sharpness of the envelope fluctuation of the signal to be handled.

FIG. 2 is a block diagram showing the details of the RF unit 2.

Referring to FIG. 2, the RF unit 2 mainly includes mixers 21 and 24, a band-pass filter 22, amplifiers (hereinafter abbreviated as amplifiers) 23 and 26, and a variable ATT 25. The variable ATT 25 is converted based on the function of up-converting the baseband signal 1a input from 1 into a frequency band necessary for transmission and generating a transmission wave 2a and the information 6a calculated by the comparison calculation circuit unit 7.
To stabilize transmission power.

FIG. 3A is a circuit diagram showing one embodiment of the detection circuit section 4, and FIG. 3B is a waveform diagram of each section in FIG. 3A.

Referring to FIGS. 3A and 3B, the detection circuit section 4 includes a diode 41, a capacitor C42, and a resistor R43, and is a coupling signal of a high-frequency signal output from the RF section 2. 3b is detected by envelope detection,
This is a circuit for converting into a component that can be processed by the A / D converter 8 at the next stage.

FIG. 4 is a block diagram showing an embodiment of the clip processing section.

Referring to FIG. 4, the clip processing unit 5
It is composed of differentiators 51 and 52, a threshold calculator 53, and a comparison processor 54. The baseband signal 1b obtained from the CONT unit 1 is detected based on discrete data 8b of detection information from the detection circuit unit 4. It is a circuit that performs processing.

FIG. 5 is a block diagram showing an embodiment of the gain fluctuation calculating circuit section 6. As shown in FIG.

Referring to FIG. 5, the gain fluctuation calculating circuit 6
Has a comparison calculation circuit unit 7 composed of a comparator 9 and a variable ATT controller 10, and an A / D converter 8. The baseband signal 5a processed by the clip processing unit 5 and the RF unit 2
Detection signal 4 of coupling signal 3b with respect to output 2a of
a in order to stabilize the output signal level based on the gain difference obtained by comparing
This is a circuit for controlling the TT25.

FIG. 6 is a block diagram showing an embodiment of the comparator 9.

Referring to FIG. 6, the comparator 9 in the comparison calculation circuit section 7 includes delay circuits 91 and 92 and averaging circuits 93 and 9
4. It has a comparison value conversion table 95, compares the discrete signal 5a from the clip processing unit 5 with the discrete signal 8a obtained by A / D-converting the output 4a of the detection circuit unit 4, and outputs the difference 93b to the variable ATT control unit. 10 has a function of converting the information into information 9a necessary for the apparatus.

Here, the delay circuits 91 and 92 and the averaging circuits 93 and 94 are circuits that absorb fluctuations in the time difference and the amplitude difference of the signal input to the comparator caused by the propagation delay and the calculation processing time.

[0036]

Next, the operation of the circuit shown in FIG. 1 will be described with reference to FIGS.

The CONT unit 1 shown in FIG. 1 modulates a digital signal to be transmitted, and generates a baseband signal serving as a reference of a transmission wave.

In the present invention, a system such as CDMA in which the same frequency is used by a plurality of users is considered. CD
In MA, power is adjusted by performing power control on a signal to be used so that the power from the base station is constant depending on the position of the user. In addition, control such as multiplexing a plurality of signals is performed to increase the efficiency of frequency use. The baseband signal 1a thus modulated is input to the RF unit 2 in FIG.

In FIG. 2, the RF unit 2 has a mixer 21 and a mixer 21 for obtaining a frequency band and a gain necessary for transmission.
24 is converted into a signal
2, unnecessary waves outside the required band are removed, and the amplifiers 23, 2
6 amplifies to the power required for transmission. Also, an offset signal 6a from a gain fluctuation calculation circuit unit 6 described later
The variable ATT 25 in the RF unit 2 is controlled to change the total gain of the RF unit 2.

The RF signal 2a thus obtained is
Although output as a transmission wave, it is actually difficult to keep the power constant due to device characteristics and temperature fluctuations. Therefore, in order to keep the output power constant, a temperature compensation circuit and an automatic gain control circuit are used.

The automatic gain control circuit feeds back the transmission power value at the output of the RF unit 2 as information and controls the variable ATT 25 in the RF unit 2 to control the transmission power gain. As a means for generating the information to be fed back, the comparator 3 in FIG.
After the signal is distributed to a level which can be compared with the above, a high-frequency signal is converted into envelope information using an envelope detection circuit unit 4 including a diode 41, a capacitor C42, and a resistor R43 as shown in FIG. A method is commonly used.

In the envelope detection circuit section 4, half-wave rectification (FIGS. 3A and 3B) of the input signal (FIG. 3A and FIG. (B))
Charge and discharge by the capacitor C42 and the resistor R43 (FIG. 3).
(A) and (B) (c)) are performed to obtain an envelope.

However, at this time, an appropriate capacitor C4
If the combination of the resistor 2 and the resistor R43 is not selected, the converted voltage will be too large or too small to perform efficient detection, making it difficult to detect accurate information. In particular, in a system such as CDMA in which a plurality of users use the same frequency, power is increased by performing power control as described above, and a plurality of signals are multiplexed in order to increase the efficiency of frequency use. Therefore, a modulated wave having a large amplitude fluctuation is handled.

In such a case, it is difficult to find an appropriate time constant for each signal, and the detected voltage varies. This is because, in the case of a modulated wave having a large waveform variation in a short time, the detection voltage is clipped by the smoothing function of the detector circuit 4, so that the power is lost and the detection voltage becomes small. Happens.

Here, in FIG. 7, the average voltage of the baseband signal 1b generated by the CONT unit 1 at a certain time T1 is given by V'1. Further, if a signal of the same level is taken out of the coupler 3, this is sent to the detection circuit unit 4.
After converting into discrete data by the A / D converter, the voltage V'2 averaged over the same time T2 as described above is V '
Should be equivalent to 1. However, in practice,
When a signal having a large amplitude fluctuation such as CDMA is handled, information on a portion having a large amplitude as shown in FIG. 7B is obtained by a value of a time constant determined by the constants of the resistor R and the capacitor C in the detection circuit section 4. Time T2
Is V2, which may be lower than the voltage V'2.

In such a case, although the desired output level is obtained, it is recognized that the level is low, and there is a problem that control is performed to increase the level. .

As described above, if the detected voltage varies, an error occurs in information to be fed back, and stable automatic gain control cannot be performed.

However, in the CDMA system, it is difficult to find appropriate time constants corresponding to the output patterns of all the modulated waves. Therefore, in the present invention, the detection circuit section in the gain fluctuation calculation circuit 6 in FIG. Assuming that the reference signal is degraded by the control unit 4, the clip processing unit 5 processes the reference data using the baseband signal generated by the CONT unit 1 as information, and then performs a comparison process by the comparator 9 to generate the reference data. Variations are absorbed.

Here, the operation of the clip processing section 5 will be described.

Referring to FIG. 4, a composite amplitude of the baseband signal is generated, and the discrete data
Is input to The differentiator 51 compares the discrete data 1b output from the CONT unit 1 and input to the clip processing unit 5.
Thus, the inclination is obtained for each sampling point. Based on the calculated inclination data 51a, the reference data is processed by the comparison processor 54 based on the threshold data 53a calculated by the threshold calculator 53.

As an operation in actual operation, the inclination information 51a obtained by the differentiator 51 is determined based on the threshold data table stored in the threshold calculator 53 as shown in FIG. Clip the reference data in case
If it is within the threshold, the data is transmitted as it is.

Here, when calculating the threshold value, it is necessary to grasp the characteristics of the detection circuit unit 4 in FIG. 1 in advance and obtain the discrete data 8b of the detection capability information. As a method of creating the discrete data 8b, the following two types of methods are exemplified.

The first method is to use CON in FIG.
Output several patterns of sample data 1b from the T unit 1,
The threshold calculator 53 compares the detection capability 8b with the detection capability 8b from the detection circuit unit 4, optimizes the threshold, and stores the data table.

More specifically, the CONT unit 1 outputs several types of CDMA data having different numbers of multiplexes and codes as sample data, and outputs a threshold value calculator 53 in the clip processing unit 5.
At the inclination information 51b of the discrete data 1b at the time of CONT output
Is compared with the slope information 52a of the discrete data 8b of the detection capability information, and a threshold data table is created under each condition. Here, the differentiators 51 and 52 each include a delay circuit, and the threshold calculator 53 has a function of inputting data of the same phase.

In the second method, the input / output characteristics of the detection circuit unit 4 are measured in advance, so that the detection capability of the detection circuit unit 4 is converted into a mathematical expression and stored in the threshold calculator 53.

On the other hand, the detection circuit section 4 receives the coupling data 3b of the transmission output generated by the RF section 2 and converts the envelope data 4a detected by sufficient charge / discharge into discrete data by the A / D converter 8. After the conversion into 8a, it is input to the comparison calculation circuit 7.

Referring to FIG. 6, in comparator 9, both input data 5a and 8a are passed through delay circuits 91 and 92 in consideration of a delay difference such as propagation and calculation. Data 91a with the timing matched,
The averaging circuits 93 and 94 perform averaging processing in an arbitrary section T, thereby obtaining average voltage values 93 a and 93.
4a is obtained. By differentially processing these data, voltage difference data 93b is obtained, and the comparison value conversion table 9
5 is converted into data 9a that can be processed by the variable ATT controller 10 in FIG.

FIG. 10 shows a specific example of the processing method in the averaging circuits 93 and 94.

Referring to FIG. 10, each averaging circuit 93,
Data from the CONT unit 1 and the detection circuit unit 4 is input to the 94 as discrete values.

In FIG. 10, an average voltage value V is calculated in an arbitrary section T with respect to discrete data of a certain time t inputted to each of them, and the voltage difference data 93b is obtained by differential processing on the obtained V1 and V2. can get.

As a comparison condition of the average voltage value data 93a and 94a, both must be compared in a logarithmic format if the data format is logarithmic conversion, and both must be compared in a linear format if the data format is linear conversion.

In FIG. 6, the comparator 9 has a comparison value conversion table 95, and converts the voltage difference data 93b obtained by the conversion table as shown in FIG. The variable ATT controller 10 that controls the amount of attenuation of the ATT 25 is provided as offset data 9a. The variable ATT control unit 10 converts the obtained offset data into a voltage value and supplies it as a control voltage to the variable ATT 25 to vary the attenuation.

For example, the voltage difference data 9 obtained from FIG.
When 3b is + 2V (2 dB lower as the transmission output level), it is converted to 0140 as offset data 9a. This is given to the variable ATT control unit 10 in FIG. 5 so that the variable ATT2 provided in the RF unit 2 in FIG.
5 is set to + 2.5V. As a result, the attenuation of the variable ATT 25 is reduced by 2 dB, and the RF unit 2
Is corrected by +2 dB.

As described above, by using, as reference data, data that has been subjected to processing for correcting a power loss due to the detection capability of the detection circuit unit 4, when a modulated wave having a large amplitude fluctuation such as CDMA is handled. Also, stable automatic gain control can be performed.

[0065]

The present invention is constructed and operates as described above, and according to the present invention, the following effects can be obtained.

With respect to the baseband signal obtained from the CONT unit 1, the clip processing unit 5 estimates the detection deterioration caused by the time constant in the detection circuit unit 4, and processes the data to obtain an amplitude such as CDMA. It is possible to absorb the deterioration of the detection voltage generated when detecting a modulated wave having a large fluctuation, and to stabilize the power at the RF output.

The reason is that the difference caused by the time constant at the time of detection can be absorbed by taking into account the degradation caused by the detection circuit unit 4 with respect to the reference data.

As described above, the detection voltage output from the detection circuit unit 4 is compared with the baseband signal 1b used as the reference data obtained from the CONT unit 1.
By clipping steep fluctuation data, CD
It is possible to absorb an error caused by deterioration of a detection voltage generated when a modulated wave having a large amplitude fluctuation such as MA is detected. As a result, an effect is obtained in which stable automatic gain control can be performed irrespective of the type of the input signal, taking into account the variation in the detection voltage at the output of the signal input to the detection circuit unit 4.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment according to the present invention.

FIG. 2 is a block diagram showing an embodiment of an RF unit 2 in FIG. 1;

3A is a circuit configuration diagram showing an example of a detection circuit unit 4 in FIG. 1, and FIG. 3B is a waveform diagram of each unit.

FIG. 4 is a circuit block diagram showing one embodiment of a clip processing unit 5 in FIG. 1;

FIG. 5 is a block diagram showing one embodiment of a gain variation calculation circuit 7 in FIG. 1;

FIG. 6 is a block diagram showing one embodiment of a comparator 9 in FIG. 5;

FIG. 7 is a diagram illustrating a principle of deterioration of an average voltage due to a time constant in FIG. 3;

FIG. 8 is an explanatory diagram showing an example of a determination method of the comparison processor 54 in FIG.

9 is an explanatory diagram showing an example of a conversion method of a comparison value conversion table 95 in FIG.

FIG. 10 is an explanatory diagram showing an example of a comparison method of the comparator 9 in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... CONT part 2 ... RF part 3 ... Coupler 4 ... Detection circuit part 5 ... Clip processing part 6 ... Gain fluctuation calculation circuit part 7 ... Comparison calculation circuit part 8 ... A / D converter 9 ... Comparator 10 ... Variable ATT control Units 21, 24 Mixer 22 BPF 23, 26 AMP 25 Variable ATT 41 Diode 42 Capacitor 43 Resistor 51, 52 Differentiator 53 Threshold calculator 54 Comparison processor 91, 92 Delay circuit 93 .. 94 averaging circuit 95 comparison value conversion circuit

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5J100 JA01 KA05 LA04 LA06 LA09 LA11 QA02 SA01 5K004 AA01 BA02 BD01 5K022 EE01 EE31

Claims (11)

[Claims] In a mobile communication system using CDMA, transmission control means for outputting a baseband signal, radio frequency means for up-converting to a frequency for transmitting a baseband signal output from the transmission control means, Detection circuit means for performing envelope detection on the signal upconverted by the radio frequency means, A / D conversion means for converting the detection output detected by the detection circuit means into discrete data, and the output from the transmission control means Clip processing means for estimating the detection deterioration caused by the time constant in the detection circuit means for the baseband signal and clipping the data having sharp fluctuations to process the data; and data output from the clip processing means and A comparison is made with the data from the detection circuit means, and A in the radio frequency means is determined according to the difference between the comparison results. A reference signal clipping control method comprising: a gain variation calculation circuit for adjusting a TT amount to absorb a difference from a true value generated by a time constant at the time of detection and stabilizing an output level. 2. The radio frequency unit includes a first mixer that mixes and outputs a baseband signal output from the transmission control unit, and removes unnecessary waves outside a required band from an output of the first mixer. A band-pass filter, a first amplifier that amplifies the output of the filter, a second mixer that mixes and outputs the output of the first amplifier,
2. The reference signal clip control method according to claim 1, further comprising: a variable ATT for variably attenuating the output of the mixer of the first embodiment, and a second amplifier for amplifying the output of the variable ATT. 3. The clip processing means includes: a first differentiator for differentiating a baseband signal from the transmission / reception control means; a second differentiator for differentiating an output signal from the A / D converter; A threshold calculator that receives output signals from the first and second differentiators and generates a threshold, and a comparison that compares an output of the first differentiator with threshold data output from the threshold calculator. And a processing unit for processing the baseband signal based on discrete data of detection information from the detection circuit means. Reference signal clip control method described in the section. 4. The threshold calculator has a threshold data table stored in the threshold calculator for the threshold data calculated by the threshold calculator, and the comparison processor includes a threshold data of the threshold data table. Is compared with the slope information obtained from the first differentiator, and the reference data is clipped when the slope information exceeds the threshold, and when the slope information is within the threshold, 4. The reference signal clip control method according to claim 3, further comprising: 5. The first and second differentiators are provided with a delay function, and the data from the first and second differentiators are input in the same phase to the threshold calculator, and the threshold data table is stored in the first and second differentiators. The control method according to claim 4, further comprising forming the reference signal. 6. The method according to claim 4, wherein, when calculating the threshold data of the threshold calculator, it is necessary to grasp characteristics of the detection circuit means in advance and obtain discrete data of detection capability information. Reference signal clip control method. 7. A method for obtaining the discrete data, wherein the transmission / reception control means includes several types of C codes having different multiplex numbers and codes.
DMA data is output as sample data, and the threshold calculator compares the slope information of the discrete data at the time of output of the transmission / reception control signal with the slope information of the discrete data of the detection capability information, and sets a threshold data table under each condition. 7. The reference signal clip control method according to claim 6, further comprising: 8. A method for obtaining the discrete data, further comprising: measuring an input / output characteristic of the detection circuit means in advance, formulating a detection capability as the detection circuit means, and storing it in the threshold calculator. 7. The reference signal clip control method according to claim 6, wherein: 9. The gain variation calculation circuit means, wherein the A / D conversion means receives an output from the detection circuit means as an input, an output from the A / D conversion means, and an output from the clip processing means. And a clipping process comprising a variable ATT controller receiving the output of the comparator and generating a control signal for controlling the variable ATT in the radio frequency means. Based on the gain difference obtained by comparing the baseband signal processed by the means and the detection signal of the coupling signal with respect to the output of the radio frequency means, the radio frequency means is used to stabilize the output signal level. The reference signal clip control method according to any one of claims 1 to 5, further comprising controlling the variable ATT. 10. The comparator in the comparison calculation circuit,
First and second delay circuits, a first averaging circuit that receives an output of the first delay circuit as an input, a second averaging circuit that receives an output of the second delay circuit as an input, The first and second
An adder for adding the output of the averaging circuit, a comparison value conversion table, and a multiplier for multiplying the output of the adder by the output of the comparison value conversion table. 10. The apparatus according to claim 9, further comprising a function of comparing a signal and a discrete signal obtained by A / D converting an output of the detection circuit, and converting a difference into information necessary for the variable ATT control unit in the comparison calculation circuit. 3. The reference signal clip control method described in 1. 11. The first and second delay circuits and the first and second averaging circuits each have a time difference and an amplitude difference of a signal input to the comparator caused by a propagation delay or a calculation processing time. 11. The reference signal clipping control method according to claim 10, further comprising a circuit for absorbing the reference signal.