TWI707567B - Device capable of compensating for amplitude-modulation to phase-modulation distortion - Google Patents

Abstract

Disclosed is a device capable of compensating for amplitude-modulation to phase-modulation distortion. The device includes a receiving circuit and a control circuit. The receiving circuit includes: an input circuit configured to generate an analog reception signal according to an radio-frequency (RF) signal; a phase-adjusting circuit configured to adjust the phase of the analog reception signal according to a control signal; and an RF-to-baseband receiving circuit configured to generate a digital reception signal according to the analog reception signal. The RF-to-baseband receiving circuit includes: a mixer configured to generate a intermediate-frequency (IF) signal according to the analog reception signal; a gain controller configured to generate a gain control signal according to the IF signal; and an analog-to-digital converter configured to generate the digital reception signal according to the gain control signal. The control circuit is configured to generate the control signal according to the digital reception signal, wherein the control signal varies with the digital reception signal.

Description

Compensation device for AM and phase distortion

The present invention relates to a distortion compensation device, especially to a compensation device for amplitude and phase modulation distortion.

The output of the power amplifier of the wireless transmitter will have amplitude-modulation to phase-modulation distortion (AM-PM distortion), which will cause the problem of spectral regrowth. The problem of spectrum proliferation makes it difficult for those skilled in the art to integrate the power amplifier into the wireless transceiver, and also reduces the performance of the transmission circuit of the wireless transceiver.

Current technologies to solve the problem of AM and phase distortion include the use of Cartesian feedback technology and adaptive digital predistortion technology. Cartesian feedback technology requires additional feedback demodulators and error amplifiers, which will increase circuit complexity and cost; Cartesian feedback can be found in textbooks (for example: Behzad Razavi, "Fundamentals of Microelectronics, 2 ^nd Edition" , ISBN-10: 9781118156322/ ISBN-13: 978-1118156322). The adaptive digital predistortion technology may require an increase in the bandwidth of the baseband signal, resulting in higher power consumption, and the coupling effect between the up-frequency path and the down-frequency path of this technology may also reduce the effect of the pre-distortion; The sexual digital predistortion technology can be found in the US Patent No. 5524286.

An object of the present invention is to provide a compensation device for AM and phase distortion to avoid the problems of the prior art.

According to an embodiment of the present invention, the compensation device for AM and phase distortion of the present invention includes a receiving circuit and a control circuit. The receiving circuit includes: an input circuit for generating an analog receiving signal according to a radio frequency signal; a phase shift adjusting circuit coupled to the input circuit for adjusting the phase shift of the analog receiving signal according to a control signal; and The RF to baseband receiving circuit is used to generate a digital receiving signal according to the analog receiving signal. The RF-to-baseband receiving circuit includes: a mixer for generating an intermediate frequency signal based on the analog received signal; a gain controller for generating a gain control signal based on the intermediate frequency signal; and an analog to digital signal The converter is used to generate the digital reception signal according to the gain control signal. The control circuit is used for generating the control signal according to the digital reception signal, wherein the control signal changes with the digital reception signal. This embodiment is suitable for a receiving circuit used in a communication device.

With regard to the features, implementation and effects of the present invention, preferred embodiments are described in detail as follows with the drawings.

The present invention discloses a compensation device for amplitude-modulation to phase-modulation distortion (AM-PM distortion), which can be applied to transmission or receiving circuits of communication devices and to audio transmission circuits, but is not limited to this . The compensation device has the advantages of easy implementation, economic cost and low power consumption.

Fig. 1 shows an embodiment of the compensation device for AM and phase distortion of the present invention. The compensation device 100 for AM and phase distortion in FIG. 1 includes a transmission circuit 110 and a control circuit 120. The transmission circuit 110 includes an amplifier circuit 112, a phase shift adjustment circuit 114, and an output circuit 116. The amplifying circuit 112 outputs an amplified signal S _AMP according to an input signal S _IN . The input signal S _IN can be a differential or single-ended signal depending on the implementation requirements. It can be a single signal or a plurality of signals (for example: in-phase (in -phase) signal and quadrature-phase (quadrature-phase) signal). The phase shift adjustment circuit 114 includes at least one of an adjustable capacitor and an adjustable inductance according to different applications. It is arranged between the amplifying circuit 114 and the output circuit 116, and adjusts the phase of the amplified signal S _AMP according to a control signal S _CTRL . Shift (phase shift); for example, the control signal S _CTRL includes a control voltage, the adjustable capacitor includes a varactor (varactor), the capacitance value of the varactor changes with the control voltage; another example The control signal S _CTRL is composed of a plurality of levels converted from a digital code. The adjustable capacitor includes a plurality of capacitor paths connected in parallel. Each capacitor path includes a capacitor element and a switch. Each switch is based on the The control signal S _CTRL is turned on or off to determine the capacitance value of the capacitor. The output circuit 116 outputs an output signal S _OUT according to the amplified signal S _AMP . The control circuit 120 generates the control signal S _CTRL according to the input signal S _IN , and the control signal S _CTRL changes with the input signal S _IN ; in other words, different input signals S _IN may correspond to different control signals S _CTRL , where The initial relationship between the input signal S _IN and the control signal S _CTRL can be selectively pre-stored in the control circuit 120, or can be selectively updated periodically/irregularly.

FIG. 2 shows an embodiment of the transmission circuit 110 of FIG. 1. In this embodiment, the transmission circuit 110 is a wireless transmission circuit (for example: a wireless transmission circuit that complies with 802.11a/b/g/n/ac specifications, a Bluetooth transmission circuit, and Narrow Band Internet of Things (NBIOT) Transmission circuit, etc.), the input signal S _IN (for example: baseband signal) includes an in-phase signal S _{IN_I} and a quadrature-phase signal S _{IN_Q} , and the amplified signal S _AMP includes a first amplified signal S _{AMP_1} and a second The amplification signal S _{AMP_2} , the control signal S _CTRL includes a first control signal S _{CTRL_1} and a second control signal S _{CTRL_2} .

As shown in FIG. 2, the amplifying circuit 112 includes an oscillation source 210 (for example: a frequency synthesizer), a first digital-to-RF-amplitude converter (DRAC) 220, and a The second DRAC 230. The oscillation source 210 provides at least one first oscillation signal LO ₁ (for example: two oscillation signals with a frequency of f _LO and phases of 0 degrees and 180 degrees) and at least one second oscillation signal LO ₂ (for example: a frequency of f _LO and Two oscillating signals with phases of 90 degrees and 270 degrees). The first DRAC 220 converts the in-phase signal S _{IN_I} into the first amplified signal S _{AMP_1} according to the at least one first oscillating signal LO ₁ . The second DRAC 230 converts the quadrature phase signal S _{IN_Q} into the second amplified signal S _{AMP_2} according to the at least one second oscillation signal LO ₂ . A further description of the amplifier circuit 112 can be found in the following documents: Morteza S. Alavi, Student Member, IEEE, Robert Bogdan Staszewski, Fellow, IEEE, Leo CN de Vreede, Senior Member, IEEE, and John R. Long, Member, IEEE, " A Wideband 2 13-bit All-Digital I/Q RF-DAC", IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 62, NO. 4, APRIL 2014.

As shown in FIG. 2, the phase shift adjustment circuit 114 includes a first resonant circuit 240 and a second resonant circuit 250. The first resonance circuit 240 adjusts the phase shift of the first amplification signal S _{AMP_1} according to the first control signal S _{CTRL_1} . The second resonance circuit 250 adjusts the phase shift of the second amplified signal S _{AMP_2} according to the second control signal S _{CTRL_2} . Each of the first resonance circuit 240 and the second resonance circuit 250 includes a capacitor and an inductance connected in parallel, and the value of the capacitor and/or the value of the inductance can be adjusted according to the control signal S _CTRL .

As shown in FIG. 2, the output circuit 116 includes a signal synthesizer 260 that _adds the first amplified signal S _{AMP_1} and the second amplified signal S _{AMP_2} to generate the output signal S _OUT . The signal synthesizer 260 alone can be a known or self-developed circuit, and its details are omitted here.

FIG. 3 shows another embodiment of the transmission circuit 110 of FIG. 1, which can be applied to an audio transmission device. In the implementation of FIG. 3, the input signal S _IN is a digital audio signal S _{IN_D} ; the amplifying circuit 112 includes a digital-to-analog converter (DAC) 310 and an audio amplifier 320, wherein the DAC 310 is based on the digital audio signal S _{IN_D} generating an analog audio signal S _{IN_A,} the audio amplifier 320 according to the class to generate the amplified signal S _aMP than the audio signal S _{IN_A;} adjusting the phase shift circuit 114 comprises a variable capacitor 330; an output circuit 116 includes an output pin 340 according to the amplified signal S _AMP outputs the output signal S _OUT .

）給控制訊號產生電路420。控制訊號產生電路420依據該計算值S _{IN_AMP}決定該控制訊號S _CTRL之強度（例如：控制電壓的電壓大小）或準位組成（例如：由該計算值S _{IN_AMP}轉換而得的複數個準位的組成，其中每個準位控制一個開關的啟閉狀態），並輸出該控制訊號S _CTRL至相移調整電路114。值得注意的是，若輸入訊號為單一訊號（例如：圖3之數位音訊訊號S _{IN_D}）且其振幅可直接地被確定，計算電路410可選擇性地被省略，此時控制訊號產生電路420直接依據該輸入訊號S _IN的振幅決定該控制訊號S _CTRL之強度或準位組成。 FIG. 4 shows an embodiment of the control circuit 120 of FIG. 1. The control circuit 120 in FIG. 4 includes a calculation circuit 410 and a control signal generation circuit 420. Computing circuit 410 according to the input signal S _IN: providing a calculated value _S IN_AMP associated with the amplitude of the input signal S _IN (e.g., (e.g., the in-phase signal and quadrature phase signal S _{IN_I S} IN_Q):

) To the control signal generating circuit 420. The control signal generating circuit 420 determines the intensity (for example, the magnitude of the control voltage) or the level composition of the control signal S _CTRL according to the calculated value S _{IN_AMP} (for example: a plurality of _levels converted from the calculated value S _{IN_AMP} ) In which each level controls the on-off state of a switch), and outputs the control signal S _CTRL to the phase shift adjustment circuit 114. It is worth noting that if the input signal is a single signal (for example, the digital audio signal S _{IN_D in} Figure 3) and its amplitude can be directly determined, the calculation circuit 410 can be optionally omitted, and the control signal generation circuit 420 is directly The intensity or level composition of the control signal S _CTRL is determined according to the amplitude of the input signal S _IN .

FIG. 5 shows an embodiment of the control signal generating circuit 420 of FIG. 4. The control signal generating circuit 420 of FIG. 5 includes a look-up circuit 510, a digital-to-analog converter (DAC) 520, and a filter circuit 530. The look-up circuit 510 outputs a digital control signal S _{CTRL_D} according to the amplitude of the input signal S _IN . DAC 520 generates an analog signal S _A according to the digital control signal S _{CTRL_D.} The filter circuit 530 (for example: low-pass filter) to produce a filtered signal as the control signal S _CTRL signal based on such ratio S _A. Notably, if the analog signal S _A is not necessary to perform filtering, the filter circuit 530 is selectively omitted, than the case such as the signal S _A to the control signal S _CTRL.

Fig. 6 shows another embodiment of the compensation device for AM and phase distortion of the present invention. Compared with FIG. 1, the compensation device 600 for AM and phase distortion compensation in FIG. 6 further includes a correction circuit 610. The correction circuit 610 outputs a correction signal S _CAL to the control circuit 120 according to the relationship between the change of the control signal S _{CTRL and} the change of the output signal S _OUT , so that the control circuit 120 determines the input signal according to the correction signal S _CAL The relationship between S _IN and the control signal S _CTRL . In an implementation example, when the input signal S _IN is a specific value (for example, when the amplitude of the input signal S _IN is a specific amplitude), the calibration circuit 610 performs at least the following steps in sequence (as shown in FIG. 7 (Shown) to determine the relationship between the change of the control signal S _{CTRL and} the change of the output signal S _IN : Step S710: Make the control signal S _CTRL change in a current direction. For example, the control signal S _CTRL is a control voltage. In this step, the control signal S _{CTRL is} increased/decreased by a predetermined voltage by one unit; for another example, the control signal S _CTRL is composed of a plurality of levels ( For example: 00011 is used to control the five switches in the aforementioned capacitance path, where level 0 is used to make the switch non-conductive, and level 1 is used to make the switch conductive), this step changes a level of the control signal S _CTRL ( For example: 00011à00111 or 00111à00011). Step S720: Perform a comparison operation to compare a current value derived from the output signal S _OUT (for example: the digital feedback signal S _FEEDBACK described below) with a previous value derived from the output signal S _OUT (for example: the following The first digital feedback signal). After the current value generating the control signal S _CTRL to a change in the latest, before the previous value produced in the last change of the control signal S _CTRL. Step S730: If the current value is less than the previous value (which means that the signal of the proliferation becomes smaller, that is, the AM-PM distortion is reduced), keep the current direction unchanged; if the current value is greater than the previous value (which means that the proliferation The signal becomes larger, that is, the AM-PM distortion becomes serious), so that the current direction is updated to the opposite of the current direction. Step S740: Repeat steps S710 to S740 in sequence until the current direction has changed at least N times, and then output the calibration signal S _CAL to indicate the best control signal S _CTRL under the condition that the input signal S _{IN is} the specific value Intensity or optimal level composition, where N is a positive integer. For example, if the current value is less than the previous value when the first comparison operation is performed, it means that the change direction of the control signal selected at the beginning is correct, then the N is a positive integer; if the first comparison operation is performed , The current value is greater than the previous value, which means that the change direction of the control signal selected at the beginning is wrong, and the N is a positive integer not less than 2. Through the above steps, the correction circuit 610 can find the best intensity or best level composition of the control signal S _CTRL corresponding to each value of the input signal S _IN .

FIG. 8 shows an embodiment of the correction circuit 610 of FIG. 6. As shown in FIG. 8, the calibration circuit 610 includes a self-mixing mixer (self-mixing mixer) 810 and an adaptive calibration circuit 820. The self-mixing mixer 810 generates a mixing signal S _MIX according to the output signal S _OUT or its derivative signal, wherein the output signal S _OUT or its derivative signal is simultaneously used as a mixing input signal S _{MIX_IN} and a mixer The oscillating signal S _{MIX_LO} is used by the self-mixing mixer 810 to generate the mixing signal S _MIX . The mixing signal S _MIX includes an accretionary signal (for example: a signal with a frequency of 2 f _BB , where f _BB is The frequency of the input signal S _IN ). The adaptive calibration circuit 820 outputs the calibration signal S _CAL to the control circuit 120 according to the relationship between the change of the control signal S _{CTRL and} the change of the mixing signal S _MIX . For example, when the control signal S _CTRL to increase up to a predetermined unit, if the one from the current value is smaller than S _MIX mixer signal from the mixer is stored in the adaptive calibration signal S _MIX circuit 820 in a previously Value (which is generated before the control signal S _CTRL changes), the adaptive calibration circuit 820 outputs the correction signal S _CAL so that the control signal S _CTRL output by the control circuit 120 increases by a preset unit; if the current value When the value is greater than the previous value, the adaptive calibration circuit 820 outputs the calibration signal S _CAL to reduce the control signal S _CTRL output by the control circuit 120 by a predetermined unit. It is worth noting that, in order to make the size of the output signal S _OUT suitable for processing by the correction circuit 610, the correction circuit 610 may optionally include a resistor (for example, an adjustable resistor) (not shown in the figure), and the resistance is based on the The output signal S _OUT outputs a step-down signal as a derivative signal of the output signal S _OUT for the self-mixing mixer 810 to generate the mixing signal S _MIX according to the step-down signal.

FIG. 9a shows an embodiment of the self-mixing mixer 810 of FIG. 8, where the dashed line represents the parasitic capacitance. Since the components shown in FIG. 9a are conventional components in the art, those skilled in the art can understand the operation of the self-mixing mixer 810 according to FIG. 9a, and the details are omitted here.

FIG. 9b shows an embodiment of the adaptive calibration circuit 820 of FIG. 8. As shown in FIG. 9b, the adaptive calibration circuit 820 includes a gain controller 910, an analog-to-digital converter (ADC) 920, and a comparison and calibration circuit 930. A gain controller (for example, a variable gain amplifier (VGA)) generates a gain control signal S _GAIN according to the mixing signal S _{MIX. The} ADC 920 generates a digital feedback signal S _FEEDBACK according to the gain control signal S _GAIN . The comparison and calibration circuit 930 compares the digital feedback signal S _FEEDBACK and a previous digital feedback signal (ie, the previously generated digital feedback signal S _FEEDBACK ) to determine and output the calibration signal S _CAL ; after the completion of the comparison of the digital feedback signal After the signal S _FEEDBACK and the previous digital feedback signal, the comparison and calibration circuit 930 uses the digital feedback signal S _FEEDBACK as the previous digital feedback signal for the next round of comparison; in an implementation example, the comparison and calibration circuit 930 The calibration circuit 930 is used to perform the steps shown in FIG. 7.

Fig. 10 shows another embodiment of the compensation device for AM and phase distortion of the present invention. The compensation device 1000 for AM and phase distortion in Fig. 10 includes a receiving circuit 1010 (for example: a wireless receiving circuit conforming to 802.11a/b/g/n/ac specifications, a Bluetooth receiving circuit, and Narrow Band Internet of Things , NBIOT) receiving circuit, etc.) and a control circuit 1020 (for example: the control circuit 120 in Figure 4). The receiving circuit 1010 includes an input circuit 1012, a phase shift adjustment circuit 1014 (for example, an adjustable capacitor), and a radio frequency to baseband receiving circuit 1016. The input circuit 1012 (for example: an adjustable resistor or a pin) generates an analog receiving signal S _{RF_A} according to a radio frequency signal S _RF . The phase shift adjustment circuit 1014 is coupled to the input circuit 1012, and adjusts the phase shift of the analog received signal S _{RF_A} according to a control signal S _CTRL . The RF-to-baseband receiving circuit 1016 generates a digital receiving signal S _BB according to the _analog receiving signal S _{RF_A} . The control circuit 1020 generates the control signal S _CTRL according to the digital reception signal S _BB , and the control signal S _CTRL changes with the digital reception signal S _BB .

FIG. 11 shows an embodiment of the RF-to-baseband receiving circuit 1016 of FIG. 10. The RF to baseband receiving circuit 1016 of FIG. 11 includes: a mixer 1110 generates an intermediate frequency signal S _IF according to the _analog received signal S _{RF_A} . A gain controller 1120 (for example, a variable gain amplifier) generates a gain control signal S _GAIN according to the intermediate frequency signal S _IF ; and an analog-to-digital converter (ADC) 1130 generates the digital reception according to the gain control signal S _GAIN The signal S _BB .

FIG. 12 shows another embodiment of the compensation device for AM and phase distortion of the present invention. Compared with FIG. 10, the compensation device 1200 for AM and phase distortion compensation in FIG. 12 further includes a correction circuit 1210 (for example, the comparison and calibration circuit 930 in FIG. 9b). The correction circuit 1210 outputs a correction signal S _CAL to the control circuit 1020 according to the relationship between the change of the digital received signal S _{BB and} the change of the control signal S _CTRL , so that the control circuit 1020 determines the digital signal according to the correction signal S _CAL The relationship between the received signal S _BB and the control signal S _CTRL . In an implementation example, the calibration circuit 1210 performs the steps of FIG. 7 except that the input signal S _{IN is} replaced by the radio frequency signal S _RF , the specific value of the input signal S _IN is replaced by the specific amplitude of the radio frequency signal S _RF , and The output signal S _{OUT is} replaced by the digital reception signal S _BB .

Since those with ordinary knowledge in the art can refer to the disclosure of the embodiments of FIGS. 1 to 9b to understand the implementation details and changes of the embodiments of FIGS. 10 to 12, repetitive and redundant descriptions are omitted here.

In summary, compared with the prior art, the compensation device for AM and phase distortion of the present invention has the advantages of easy implementation, economical cost, and low power consumption.

Although the embodiments of the present invention are as described above, these embodiments are not used to limit the present invention. Those skilled in the art can make changes to the technical features of the present invention based on the explicit or implicit content of the present invention. All such changes may belong to the scope of patent protection sought by the present invention. In other words, the scope of patent protection of the present invention shall be subject to the scope of the patent application in this specification.

100 Compensation device for amplitude modulation and phase modulation distortion 110 Transmission circuit 120 Control circuit 112 Amplification circuit 114 Phase shift adjustment circuit 116 Output circuit S _IN input signal S _AMP amplified signal S _CTRL control signal S _OUT output signal S _{IN_I} In-phase signal S _{IN_Q} Quadrature phase Signal S _{AMP_1} First amplification signal S _{AMP_2} Second amplification signal S _{CTRL_1} First control signal S _{CTRL_2} Second control signal 210 Oscillation source 220 First DRAC (first digital to RF amplitude converter) 230 Second DRAC (second digital To RF amplitude converter) LO ₁ at least one first oscillation signal LO ₂ at least one second oscillation signal 240 first resonance circuit 250 second resonance circuit 260 signal synthesizer S _{IN_D} digital audio signal S _{IN_A} analog audio signal 310 DAC (digital To analog converter) 320 audio amplifier 330 adjustable capacitor 340 output pin 410 calculation circuit 420 control signal generation circuit S _{IN_AMP} calculation value 510 look-up circuit 520 DAC (digital-to-analog converter) 530 filter circuit S _{CTRL_D} digital control signal S _A analog signal 600 compensation device for amplitude and phase modulation distortion 610 correction circuit S _CAL correction signal S710~S740 step 810 self-mixing mixer 820 adaptive calibration circuit S _MIX mixing signal S _{MIX_IN} mixing input signal S _{MIX_LO} mixer Oscillation signal 910 Gain controller 920 ADC (analog-to-digital converter) 930 Comparison and calibration circuit S _GAIN gain control signal S _FEEDBACK Digital feedback signal 1000 Amplitude and phase modulation distortion compensation device 1010 Receive circuit 1020 Control circuit 1012 Input circuit 1014 phase Shift adjustment circuit 1016 RF to baseband receiving circuit S _RF radio frequency signal S _{RF_A} analog receiving signal S _BB digital receiving signal 1110 mixer 1120 gain controller 1130 ADC (analog to digital converter) S _IF intermediate frequency signal S _GAIN gain control Signal 1200 Amplitude and Phase Modulation Distortion Compensation Device 1210 Correction Circuit

[Figure 1] shows an embodiment of the compensation device for amplitude and phase modulation of the present invention; [Figure 2] shows an embodiment of the transmission circuit of Figure 1; [Figure 3] shows another embodiment of the transmission circuit of Figure 1; [Figure 4] shows an embodiment of the control circuit of Figure 1; [Figure 5] shows an embodiment of the control signal generating circuit of Figure 4; [Figure 6] shows another embodiment of the compensation device for amplitude and phase modulation of the present invention; [Figure 7] shows the steps performed by the calibration circuit in Figure 6; [Figure 8] shows an embodiment of the correction circuit of Figure 6; [Figure 9a] shows an embodiment of the self-mixing mixer of Figure 8; [Figure 9b] shows an embodiment of the adaptive calibration circuit of Figure 8; [Figure 10] shows another embodiment of the compensation device for AM and phase distortion of the present invention; [Figure 11] shows an embodiment of the RF to baseband receiving circuit of Figure 10; and [Figure 12] shows another embodiment of the compensation device for AM and phase distortion of the present invention.

100 Compensation device for amplitude and phase modulation distortion 110 Transmission circuit 120 Control circuit 112 Amplification circuit 114 Phase shift adjustment circuit 116 Output circuit S _IN input signal S _AMP amplified signal S _CTRL control signal S _OUT output signal

Claims (6)

An amplitude-modulation to phase-modulation (AM-PM) distortion compensation device, including: A receiving circuit, including: An input circuit for generating an analog receiving signal according to a radio frequency signal; A phase shift adjustment circuit coupled to the input circuit for adjusting the phase shift of the analog received signal according to a control signal; and An RF to baseband receiving circuit for generating a digital receiving signal according to the analog receiving signal; and A control circuit for generating the control signal according to the digital reception signal, wherein the control signal changes with the digital reception signal, The RF to baseband receiving circuit includes: A mixer for generating an intermediate frequency signal according to the analog received signal; A gain controller for generating a gain control signal according to the intermediate frequency signal; and An analog-to-digital converter is used to generate the digital reception signal according to the gain control signal. For example, the compensation device for amplitude modulation and phase modulation distortion described in the scope of the patent application further includes a correction circuit that outputs a correction signal to the control signal according to the relationship between the change of the digital received signal and the change of the control signal The control circuit enables the control circuit to determine the relationship between the digital reception signal and the control signal according to the correction signal. For example, the compensation device for amplitude modulation and phase modulation distortion described in item 2 of the scope of application, wherein when the amplitude of the radio frequency signal is a specific amplitude, the correction circuit executes at least the following steps to determine the change of the digital received signal and the The relationship between the change of the control signal: make the control signal change in a current direction; perform a comparison operation to compare a current value of the digital reception signal with a previous value of the digital reception signal, where the current value is generated After the last change of the control signal, the previous value was generated before the last change of the control signal; if the current value is less than the previous value, keep the current direction unchanged, if the current value is greater than the previous value , Update the current direction to be the inverse of the current direction; repeat the above steps in sequence until the current direction changes at least N times, and then output the correction signal to indicate that the radio frequency signal is the specific amplitude The optimal strength or optimal level composition of the control signal, where N is a positive integer. The compensation device for amplitude modulation and phase modulation distortion as described in item 1 of the scope of patent application, wherein the control circuit includes: A control signal generating circuit is used to determine the intensity or level composition of the control signal according to the amplitude of the digital received signal, and output the control signal to the phase shift adjustment circuit. For the compensation device for amplitude modulation and phase modulation distortion described in item 4 of the scope of patent application, the control signal generating circuit includes: a calculation circuit for generating a calculated value related to the amplitude of the digital received signal according to the digital received signal ; A look-up circuit for outputting a digital control signal according to the calculated value; and a digital-to-analog converter for generating an analog signal according to the digital control signal, wherein the analog signal or a filter signal of the analog signal As the control signal. The compensation device for amplitude and phase modulation distortion described in item 4 of the scope of patent application, wherein the control signal generating circuit includes: A look-up circuit for outputting a digital control signal according to the amplitude of the input signal; and A digital-to-analog converter is used to generate an analog signal according to the digital control signal, wherein the analog signal or a filter signal of the analog signal is used as the control signal.

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