A method, apparatus and receiver for calibrating a receiver

Abstract

The application discloses a kind of calibration method, device and receiver of receiver, method includes: by the sampling of radio frequency signal and local oscillator signal input to receiver, first road digital output signal and second road digital output signal are calculated to obtain;Set digital quadrature mixing signal, and according to the signal amplitude of digital output signal, signal power is obtained;Further determine configuration value, to make initialization mismatch calibration control parameter, and using current configuration value carries out cyclic calculation, to update mismatch calibration control parameter, and then the configuration value corresponding to all mismatch calibration control parameters is compared, obtains final fixed mismatch calibration control parameter;According to mismatch calibration control parameter, the digital signal output is compensated and calibrated.The application solves the technical problems that calibration needs complex calculation and algorithm in the prior art, the requirement of higher hardware resources is not simple and efficient, easy to calibrate failure and calibration inaccuracy.

Description

Technical Field

[0001] This invention relates to the field of radio frequency communication technology, and in particular to a calibration method, apparatus and receiver for a receiver. Background Technology

[0002] Radio frequency (RF) transceiver chips are a crucial component of wireless communication systems, used for receiving and transmitting wireless signals. In a receiver, maintaining the orthogonality of the receiving channels is essential for proper demodulation and recovery of the original signal. However, due to manufacturing and environmental factors, receivers often suffer from orthogonal imbalance, meaning the gain and phase in the receiving channels are not perfectly aligned. This inconsistency makes it impossible to completely distinguish between the useful signal and the mirror signal, thus affecting receiver performance.

[0003] Currently, the main approach to addressing receiver quadrature imbalance is to estimate and calibrate the receiver's quadrature imbalance using mathematical models and computational algorithms. However, this method requires complex calculations and algorithms, places high demands on hardware resources, and is neither simple nor efficient. Furthermore, it has low tolerance for noise and other interference, which can easily lead to calibration failure or inaccurate calibration in real-world application scenarios with the interference and noise conditions encountered.

[0004] Therefore, there is an urgent need for a simple, effective, fault-tolerant, and easy-to-implement method for receiver quadrature imbalance calibration. Summary of the Invention

[0005] This invention provides a calibration method, apparatus, and receiver for a receiver, to solve the technical problems in the prior art where calibration requires complex calculations and algorithms, has high hardware resource requirements, is not simple and efficient enough, and is prone to calibration failure and inaccuracy.

[0006] To address the aforementioned technical problems, embodiments of the present invention provide a receiver calibration method, comprising:

[0007] By sampling the radio frequency signal and local oscillator signal input to the receiver, the first digital output signal and the second digital output signal after digital signal conversion are calculated.

[0008] Set up a digital quadrature mixer signal, and obtain the power of the first signal and the power of the second signal based on the signal amplitudes of the first digital output signal and the second digital output signal;

[0009] Based on the power of the first signal and the power of the second signal, a configuration value is determined to initialize the mismatch calibration control parameters. The current configuration value is then used to perform iterative calculations to update the mismatch calibration control parameters. Finally, the configuration values ​​corresponding to all mismatch calibration control parameters are compared to obtain the final fixed mismatch calibration control parameters.

[0010] The output digital signal is compensated and calibrated according to the mismatch calibration control parameters, thereby achieving the calibration of the receiver.

[0011] As a preferred embodiment, the step of sampling the radio frequency signal and the local oscillator signal input to the receiver to calculate the first digital output signal and the second digital output signal after digital signal conversion is specifically as follows:

[0012] The receiver receives the radio frequency signal sent to the receiver by the radio frequency signal generator and receives the local oscillator signal through the channel, thereby sampling to obtain the radio frequency signal and the local oscillator signal;

[0013] The radio frequency signal and the local oscillator signal are mixed by a mixer to obtain a mixed signal. The mixed signal is then filtered out for high frequencies to obtain a mid-to-low frequency signal. The mid-to-low frequency signal includes an intermediate frequency signal and a low frequency signal. Both the intermediate frequency signal and the low frequency signal include a useful signal and a mirror signal. The useful signal and the mirror signal have the same frequency and are 180° out of phase. The frequency of the intermediate frequency signal is higher than that of the low frequency signal.

[0014] The intermediate frequency signal and the low frequency signal are respectively converted into digital signals to obtain the first digital output signal and the second digital output signal.

[0015] As a preferred embodiment, the step of setting a digital quadrature mixer signal and obtaining the power of the first signal and the power of the second signal based on the signal amplitudes of the first and second digital output signals specifically involves:

[0016] The intermediate frequency angular frequency and the low frequency angular frequency are calculated based on the intermediate frequency signal and the low frequency signal, respectively.

[0017] Based on the intermediate frequency angular frequency, the digital quadrature mixing signal is set as the first calculated value, and based on the first calculated value, the first digital output signal and the second digital output signal are respectively converted into a first DC signal and a first signal to be filtered out.

[0018] Based on the low-frequency angular frequency, the digital quadrature mixing signal is set as the second calculated value, and based on the second calculated value, the second digital output signal and the first digital output signal are respectively converted into a second DC signal and a second signal to be filtered out.

[0019] The first signal to be filtered and the second signal to be filtered are filtered out, and the first DC signal and the second DC signal are retained, thereby obtaining the first signal power corresponding to the first DC signal and the second signal power corresponding to the second DC signal.

[0020] As a preferred embodiment, determining the configuration value based on the power of the first signal and the power of the second signal includes:

[0021] The image suppression value is calculated based on the power of the first signal and the power of the second signal, and is used as the configuration value;

[0022] Alternatively, the power of the second signal can be used as a configuration value.

[0023] As a preferred embodiment, the initialization of the mismatch calibration control parameters and the cyclic calculation using the current configuration values ​​update the mismatch calibration control parameters. Then, by comparing the configuration values ​​corresponding to all mismatch calibration control parameters, the final fixed mismatch calibration control parameters are obtained. Specifically:

[0024] Initialize the mismatch calibration control parameters by performing iterative calculations using the current configuration values. During the iterative calculation, the mismatch calibration control parameters are set twice, in both the forward and reverse directions, using the binary search method of the control word. The first and second components corresponding to the current configuration value are calculated for both the forward and reverse directions. Based on the first and second components obtained from the two mismatch calibration control parameter settings, the corresponding mismatch calibration control parameter is selected as the first mismatch calibration control parameter for the next iterative calculation. This process continues until the mismatch calibration control parameters corresponding to all control words are obtained, at which point the parameters are fixed to obtain the final mismatch calibration control parameters. One iteration corresponds to one control word.

[0025] As a preferred embodiment, the mismatch calibration control parameters include phase mismatch calibration control parameters and amplitude mismatch calibration control parameters; the phase mismatch calibration control parameters and the amplitude mismatch calibration control parameters are obtained through separate iterative calculations.

[0026] As a preferred embodiment, the step of compensating and calibrating the output digital signal according to the mismatch calibration control parameters to achieve receiver calibration specifically involves:

[0027] The phase mismatch calibration control parameters and the amplitude mismatch calibration control parameters are used to compensate and calibrate the phase and amplitude of the useful signal after digital signal conversion, and the phase mismatch calibration control parameters and the amplitude mismatch calibration control parameters are used to compensate and calibrate the phase and amplitude of the mirror signal after digital signal conversion, thereby realizing the calibration of the quadrature imbalance of the receiver.

[0028] Accordingly, the present invention also provides a calibration device for a receiver, comprising: a sampling module, a quantization module, a decision loop module, and a calibration module;

[0029] The sampling module is used to calculate the first digital output signal and the second digital output signal after digital signal conversion by sampling the radio frequency signal and the local oscillator signal input to the receiver.

[0030] The quantization module is used to set the digital quadrature mixing signal and obtain the power of the first signal and the power of the second signal based on the signal amplitudes of the first digital output signal and the second digital output signal.

[0031] The determination loop module is used to determine the configuration value based on the power of the first signal and the power of the second signal, so as to initialize the mismatch calibration control parameter, and perform loop calculation using the current configuration value to update the mismatch calibration control parameter. Then, after comparing the configuration values ​​corresponding to all mismatch calibration control parameters, the final fixed mismatch calibration control parameter is obtained.

[0032] The calibration module is used to compensate and calibrate the output digital signal according to the mismatch calibration control parameters, thereby calibrating the receiver.

[0033] Accordingly, the present invention also provides a receiver for performing the calibration method of the receiver as described in any of the above claims, comprising a radio frequency signal generator, an input module, an orthogonal compensation module, a sampling module, and a digital algorithm module connected in sequence; wherein the input terminal of the orthogonal compensation module is also connected to the output terminal of the digital algorithm module;

[0034] The radio frequency signal generator is used to generate radio frequency signals; the input module is used to preprocess the radio frequency signals.

[0035] The sampling module is used to sample the signal output by the input module;

[0036] The digital algorithm module is used to quantize and evaluate the sampled signal, and then feed the quantized and evaluated signal back to the orthogonal compensation module.

[0037] The orthogonal compensation module is used to compensate and calibrate the orthogonal imbalance of the input radio frequency signal based on the quantized evaluation signal.

[0038] As a preferred embodiment, the input module includes: a down-conversion mixer, a first receiver intermediate frequency circuit, a second receiver intermediate frequency circuit, a first digital-to-analog converter, and a second digital-to-analog converter; the sampling module includes: a digital quadrature mixer, a first non-recursive filter, and a second non-recursive filter.

[0039] The input terminal of the downconversion mixer is connected to the output terminal of the radio frequency signal generator. The input terminal of the downconversion mixer is also connected to the channel for transmitting the local oscillator signal. The output terminals of the downconversion mixer are both connected to the input terminals of the first receiver intermediate frequency circuit and the second receiver intermediate frequency circuit. The output terminals of the first receiver intermediate frequency circuit and the second receiver intermediate frequency circuit are respectively connected to the first digital-to-analog converter and the second digital-to-analog converter. The input terminal of the digital quadrature mixer is connected to the output terminal of the quadrature compensation module. The output terminal of the digital quadrature mixer is respectively connected to the input terminals of the first non-recursive filter and the second non-recursive filter. The output terminals of the first non-recursive filter and the second non-recursive filter are both connected to the input terminal of the digital algorithm module.

[0040] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0041] The technical solution of this invention obtains a first digital output signal and a second digital output signal by sampling the radio frequency signal and local oscillator signal input to the receiver, and then obtains the first signal power and the second signal power. After determining the configuration value, the mismatch calibration control parameter is cyclically calculated with the configuration value to obtain the final fixed mismatch calibration control parameter, thereby realizing the calibration of the orthogonal imbalance of the signal. Compared with the prior art, this invention does not require complex calculations and mathematical calculations, has a simple principle, and does not require complex hardware facilities, making it easy to implement. At the same time, the cyclic calculation of the mismatch calibration control parameter and the configuration value can successively approximate a high fault tolerance rate, thereby improving the calibration effect and adjustment accuracy. Attached Figure Description

[0042] Figure 1 : A flowchart illustrating the steps of a receiver calibration method provided in an embodiment of the present invention;

[0043] Figure 2 : A frame diagram of the receiver provided in an embodiment of the present invention;

[0044] Figure 3 : This is a sampling diagram of the receiver provided in an embodiment of the present invention;

[0045] Figure 4 : A schematic diagram of the dichotomy method provided in an embodiment of the present invention;

[0046] Figure 5 : This is a flowchart illustrating the orthogonal unbalance calibration method provided in an embodiment of the present invention;

[0047] Figure 6 : This is a structural diagram of the calibration device for the receiver provided in an embodiment of the present invention;

[0048] Figure 7 : This is a schematic diagram of the orthogonal compensation module architecture provided in an embodiment of the present invention. Detailed Implementation

[0049] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0050] Example 1

[0051] Please refer to Figure 1 A receiver calibration method provided in this embodiment of the invention includes the following steps S101-S104:

[0052] Step S101: By sampling the radio frequency signal and the local oscillator signal input to the receiver, the first digital output signal and the second digital output signal after digital signal conversion are calculated.

[0053] In a preferred embodiment, the step of sampling the radio frequency signal and the local oscillator signal input to the receiver to calculate the first digital output signal and the second digital output signal after digital signal conversion is specifically as follows:

[0054] The receiver receives radio frequency (RF) signals sent from an RF signal generator to a receiver and receives local oscillator (LO) signals through a channel, thereby sampling to obtain RF signals and LO signals. The RF signals and LO signals are then mixed using a mixer to obtain a mixed signal, which is then filtered for high frequencies to obtain a mid-to-low frequency (MCF) signal. The MCF signal includes an intermediate frequency (IF) signal and a low-frequency (LFM) signal, both of which include a useful signal and a mirror signal. The useful signal and the mirror signal have the same frequency and are 180° out of phase. The IF signal has a higher frequency than the LFM signal. The IF signal and LFM signal are then digitally converted to obtain a first digital output signal and a second digital output signal.

[0055] In this embodiment, by receiving the radio frequency (RF) signal sent to the receiver by the RF signal generator and the local oscillator (LO) signal received through the channel, the RF signal and LO signal can be effectively sampled. Simultaneously, the RF signal and LO signal are mixed by a mixer to obtain a mixed signal. The mixing process extracts the frequency information from the RF signal and converts it into a mid-to-low frequency (MCF) signal. High-frequency filtering of the mixed signal removes unwanted frequency components, resulting in a pure MCF signal. The MCF signal includes an intermediate frequency (IF) signal and a low-frequency (LF) signal, both of which include a useful signal and a mirror signal. The useful signal and the mirror signal have the same frequency but differ by 180°. Furthermore, the IF signal and the LF signal are digitally converted to obtain a first digital output signal and a second digital output signal. Digital signal conversion improves the signal's anti-interference capability and transmittance. Preferably, the LCF signal is in the range of 30-150Hz, and the IF signal is in the range of 150-500Hz.

[0056] In this embodiment, please refer to Figure 2 This is a block diagram of the receiver in this invention. In this diagram, RF Signal Generator is the radio frequency signal generator, RXIF is the receiver intermediate frequency circuit, Mixer is the down-conversion mixer, ADC is the digital-to-analog converter, IQtune is the quadrature compensation module, Quad Mixer is the digital quadrature mixer, FIR is the non-recursive filter, and Algorithm is the digital algorithm module. Further, DI... <bit-1:0>,DQ <bit-1:0>These are all ADC output signals, primarily the original signals from the RF receiver, and are digital signals. The bit (BIT) represents the physical number of bits in the ADC. NCO_I and NCO_Q are both digital quadrature mixer digital local oscillator signals, and different signals can be output according to test requirements. ph_tune <b-1:0>,a_tune <a-1:0>These are the phase mismatch calibration control parameters and amplitude mismatch calibration control parameters, respectively. B and A represent the number of control bits, which can be set differently depending on the range and precision. The highest bit is the sign bit, with 1 indicating a negative value and 0 indicating a positive value. SI <bit-1:0>and SQ <bit-1:0>The sampled signal can be used as data for algorithmic calculations. The RXIF filter's spectral characteristics suppress signals outside its filtering spectrum, as does the FIR filter's spectral characteristics.

[0057] In this embodiment, please refer to Figure 2 and 3 Based on the receiver's block diagram, the RF signal generator generates and transmits at a frequency of f. rf The radio frequency signal, thus interacting with the original down-conversion frequency f in the radio frequency receiver. lo The local oscillator signal is down-converted to a low-to-medium frequency signal in the down-conversion mixer. This signal is then passed through the receiver's intermediate frequency circuit to filter out unwanted signals and amplify the useful signal, thus obtaining the useful signal and its image signal. Where f... rf +f lo High-frequency signals will be filtered out by RXIF, f if =f rf -f lo The signal will be preserved. However, due to the presence of quadrature imbalance (phase and gain mismatch), the intermediate frequency signal will have a -f value. if The frequency components of this signal are mirror images of the useful signal, with the same frequency but a 180° phase difference. Where f rf f is the frequency of the radio frequency signal generated by RF Signal gen; lo f is the local oscillator signal frequency; if f is the intermediate frequency signal frequency after down-conversion; NCO This is the frequency of the digital quadrature mixer.

[0058] In this embodiment, the low-to-medium frequency signal (analog signal) can be converted into a digital signal by a digital-to-analog converter, corresponding to DI. <bit-1:0>And DQ <bit-1:0>, among which, DI <bit-1:0>DQ is the first digital output signal corresponding to the intermediate frequency signal. <bit-1:0>This is the second digital output signal corresponding to the low-frequency signal.

[0059] Step S102: Set the digital quadrature mixing signal, and obtain the power of the first signal and the power of the second signal based on the signal amplitudes of the first digital output signal and the second digital output signal.

[0060] In a preferred embodiment, the step of setting a digital quadrature mixer signal and obtaining the power of the first signal and the power of the second signal based on the signal amplitudes of the first and second digital output signals specifically involves:

[0061] Based on the intermediate frequency signal and the low frequency signal, the intermediate frequency angular frequency and the low frequency angular frequency are calculated respectively; based on the intermediate frequency angular frequency, the digital quadrature mixer signal is set as the first calculated value, and based on the first calculated value, the first digital output signal and the second digital output signal are converted into a first DC signal and a first signal to be filtered, respectively; based on the low frequency angular frequency, the digital quadrature mixer signal is set as the second calculated value, and based on the second calculated value, the second digital output signal and the first digital output signal are converted into a second DC signal and a second signal to be filtered, respectively; the first signal to be filtered and the second signal to be filtered are filtered out, and the first DC signal and the second DC signal are retained, thereby corresponding to the first signal power of the first DC signal and the second signal power of the second DC signal.

[0062] In this embodiment, the intermediate frequency (IF) and low frequency (LFM) angular frequencies can be calculated using the IF and LFM signals respectively, thereby accurately obtaining the signal frequency information. Simultaneously, the IF angular frequency is used to set the digital quadrature mixer signal as the first calculated value. Based on this value, the first and second digital output signals are converted to obtain the corresponding DC signal and the signal to be filtered, allowing for the extraction of desired signal components and the removal of unwanted ones. Similarly, the LFM angular frequency is used to set the digital quadrature mixer signal as the second calculated value. Based on this value, the second and first digital output signals are converted to obtain the corresponding DC signal and the signal to be filtered, further allowing for the extraction of desired signal components and the removal of unwanted ones. Filtering the first and second signals removes unwanted signal components, resulting in a clean signal. This allows for the acquisition of the first signal power corresponding to the first DC signal and the second signal power corresponding to the second DC signal after retaining the first and second DC signals, enabling independent power measurement and analysis of different signals.

[0063] In this embodiment, the NCO digital quadrature mixer digital local oscillator signal is first set to... Where, ω if =2πf if At this time, the useful signal f if and mirror signal -f if These will become DC signals and signals with a frequency of -2f, respectively. if The signal, where -2f if The frequency signal will be filtered out by FIR, while the DC signal will be retained, thus obtaining the useful signal power information, corresponding to the first signal power of the first DC signal. Furthermore, the NCO digital quadrature mixer digital local oscillator signal is set to... At this time, the useful signal f if and mirror signal -f if They will each become frequencies of 2f if Signals and DC signals, 2f if The signal will be filtered out by FIR, and the DC signal will be retained, thus obtaining the power information of the mirror signal, which corresponds to the power of the second signal of the second DC signal.

[0064] Step S103: Determine the configuration value based on the power of the first signal and the power of the second signal to initialize the mismatch calibration control parameters, and perform iterative calculations using the current configuration value to update the mismatch calibration control parameters. Then, compare the configuration values ​​corresponding to all mismatch calibration control parameters to obtain the final fixed mismatch calibration control parameters.

[0065] As a preferred embodiment, determining the configuration value based on the power of the first signal and the power of the second signal includes:

[0066] Based on the power of the first signal and the power of the second signal, the image suppression value is calculated and used as the configuration value; or, the power of the second signal is used as the configuration value.

[0067] In this embodiment, the amplitude of the useful signal obtained during the sampling process is I-channel V. sig_i (Corresponding to intermediate frequency signal), Q-channel V sig_q (Corresponding to low-frequency signals), the amplitude of the mirror signal is I-channel V. img_i (corresponding to intermediate frequency signal), Q-channel V img_q (Corresponding to low-frequency signals), it needs to be converted into power information, and the useful signal power is among them. Mirror signal power

[0068] In this embodiment, the mirror suppression value R can be calculated. img =P sig / P img Alternatively, only P can be taken. img This is used as a configuration value for judgment. When R is taken... img During the judgment process, the image suppression values ​​of the two calibrations are compared, and the ph_tune and a_tune with the larger image suppression value are selected to proceed to the next loop. When P is selected... img During the judgment process, ph_tune and a_tune with lower image power are selected to proceed to the next loop. Both the image suppression value and the image power can be configured values ​​used for comparison and judgment.

[0069] In a preferred embodiment, the initialization of the mismatch calibration control parameters and the cyclic calculation using the current configuration values ​​to update the mismatch calibration control parameters, followed by comparing the configuration values ​​corresponding to all mismatch calibration control parameters to obtain the final fixed mismatch calibration control parameters, specifically:

[0070] Initialize the mismatch calibration control parameters by performing iterative calculations using the current configuration values. During the iterative calculation, the mismatch calibration control parameters are set twice, in both the forward and reverse directions, using the binary search method of the control word. The first and second components corresponding to the current configuration value are calculated for both the forward and reverse directions. Based on the first and second components obtained from the two mismatch calibration control parameter settings, the corresponding mismatch calibration control parameter is selected as the first mismatch calibration control parameter for the next iterative calculation. This process continues until the mismatch calibration control parameters corresponding to all control words are obtained, at which point the parameters are fixed to obtain the final mismatch calibration control parameters. One iteration corresponds to one control word.

[0071] In this embodiment, please refer to Figure 4 The decision control loop uses a binary search method. Each time, ph_tune or a_tune is configured twice. Data is then acquired according to the sampling principle, and a decision is made based on the quantization comparison process, thus looping until + / -2 is reached in the binary search. 0 After calibration is complete, the bit represents the control word, corresponding to A or B. The mismatch calibration control parameters are initialized, thereby initializing ph_tune or a_tune. Taking ph_tune as an example, ph_tune is set to 11xxx and 01xxx respectively. Here, the control word is in two's complement form, where 1 represents a negative value and 0 represents a positive value, corresponding to -2 respectively. B-1 and 2 B-1 .like Figure 4 The binary search method requires determining the results in both directions; therefore, from the ph_tune setting to R... img_p / R img_m The process needs to be executed twice to obtain R. img_p and R img_m The value of R is used for comparison. img_p xx_tune+2 n Mirror suppression, R img_m For xx_tune-2 n Mirror image suppression. Then, the mirror image suppression results R are compared. img_p and R img_m This determines the value of ph_tune in the current loop, so that in the next loop, ph_tune is configured with the previous value, and then subtracted by 2. B-2 and 2 B-2 This process is repeated until the last comparison is completed. Finally, the ph_tune value is fixed, and the a_tune calibration procedure begins, which is identical to the ph_tune process.

[0072] In this embodiment, please refer to Figure 5 This is the complete process of the present invention. The range of n is B-1 to 0 for ph_tune and A-1 to 0 for a_tune. xx_tune: the two calibrations correspond to ph_tune and a_tune respectively. xx_tune is the two calibrations corresponding to ph_tune and a_tune respectively. In this process, the process needs to be looped twice, corresponding to ph_tune calibration and a_tune calibration respectively.

[0073] Step S104: Based on the mismatch calibration control parameters, the output digital signal is compensated and calibrated to achieve the calibration of the receiver.

[0074] As a preferred embodiment, the mismatch calibration control parameters include phase mismatch calibration control parameters and amplitude mismatch calibration control parameters; the phase mismatch calibration control parameters and the amplitude mismatch calibration control parameters are obtained by separate iterative calculations.

[0075] In a preferred embodiment, the step of compensating and calibrating the output digital signal according to the mismatch calibration control parameters to achieve receiver calibration specifically involves:

[0076] The phase mismatch calibration control parameters and the amplitude mismatch calibration control parameters are used to compensate and calibrate the phase and amplitude of the useful signal after digital signal conversion, and the phase mismatch calibration control parameters and the amplitude mismatch calibration control parameters are used to compensate and calibrate the phase and amplitude of the mirror signal after digital signal conversion, thereby realizing the calibration of the quadrature imbalance of the receiver.

[0077] In this embodiment, because this technical solution can effectively calibrate the receiver quadrature imbalance in the RF transceiver chip, it has wide applications in wireless communication, radar systems, satellite communication, and other fields. In the field of wireless communication, the RF transceiver chip is one of the core components of a wireless communication system. By using this technical solution, the impact of receiver quadrature imbalance on the communication system can be reduced, improving receiver performance and reliability. Therefore, this technical solution can be applied to various wireless communication fields such as mobile communication, wireless networks, and the Internet of Things. In the field of radar systems, receiver quadrature imbalance can lead to increased measurement errors in the radar system, affecting the accuracy of target detection and tracking. By using this technical solution for calibration, the error of the radar system can be reduced, improving the accuracy of target detection and tracking. Therefore, this technical solution can be applied to various radar systems such as military radar and civilian radar. In the field of satellite communication, the RF transceiver chip is an important component of a satellite communication system. By using this technical solution, the impact of receiver quadrature imbalance on the satellite communication system can be reduced, improving communication quality and reliability. Therefore, this technical solution can be applied to various satellite communication fields such as satellite communication systems and satellite broadcasting systems.

[0078] Understandably, due to the advanced nature and wide range of applications of this technical solution, it can meet the needs of receiver quadrature unbalance calibration in fields such as wireless communication, radar systems, and satellite communication, and has good technical application prospects and market demand.

[0079] Implementing the above embodiments has the following effects:

[0080] The technical solution of this invention obtains a first digital output signal and a second digital output signal by sampling the radio frequency signal and local oscillator signal input to the receiver, and then obtains the first signal power and the second signal power. After determining the configuration value, the mismatch calibration control parameter is cyclically calculated with the configuration value to obtain the final fixed mismatch calibration control parameter, thereby realizing the calibration of the orthogonal imbalance of the signal. Compared with the prior art, this invention does not require complex calculations and mathematical calculations, has a simple principle, and does not require complex hardware facilities, making it easy to implement. At the same time, the cyclic calculation of the mismatch calibration control parameter and the configuration value can successively approximate a high fault tolerance rate, thereby improving the calibration effect and adjustment accuracy.

[0081] Example 2

[0082] Please see Figure 6 The present invention provides a receiver calibration device, comprising: a sampling module 201, a quantization module 202, a decision loop module 203, and a calibration module 204.

[0083] The sampling module 201 is used to calculate the first digital output signal and the second digital output signal after digital signal conversion by sampling the radio frequency signal and the local oscillator signal input to the receiver.

[0084] The quantization module 202 is used to set the digital quadrature mixing signal and obtain the power of the first signal and the power of the second signal based on the signal amplitudes of the first digital output signal and the second digital output signal.

[0085] The determination loop module 203 is used to determine the configuration value based on the power of the first signal and the power of the second signal, so as to initialize the mismatch calibration control parameter, and perform loop calculation using the current configuration value to update the mismatch calibration control parameter. Then, after comparing the configuration values ​​corresponding to all mismatch calibration control parameters, the final fixed mismatch calibration control parameter is obtained.

[0086] The calibration module 204 is used to compensate and calibrate the output digital signal according to the mismatch calibration control parameters, thereby calibrating the receiver.

[0087] As a preferred embodiment, the step of sampling the radio frequency signal and the local oscillator signal input to the receiver to calculate the first digital output signal and the second digital output signal after digital signal conversion is specifically as follows:

[0088] The receiver receives the radio frequency signal sent to the receiver by the radio frequency signal generator and receives the local oscillator signal through the channel, thereby sampling to obtain the radio frequency signal and the local oscillator signal;

[0089] The radio frequency signal and the local oscillator signal are mixed by a mixer to obtain a mixed signal. The mixed signal is then filtered out for high frequencies to obtain a mid-to-low frequency signal. The mid-to-low frequency signal includes an intermediate frequency signal and a low frequency signal. Both the intermediate frequency signal and the low frequency signal include a useful signal and a mirror signal. The useful signal and the mirror signal have the same frequency and are 180° out of phase. The frequency of the intermediate frequency signal is higher than that of the low frequency signal.

[0090] The intermediate frequency signal and the low frequency signal are respectively converted into digital signals to obtain the first digital output signal and the second digital output signal.

[0091] As a preferred embodiment, the step of setting a digital quadrature mixer signal and obtaining the power of the first signal and the power of the second signal based on the signal amplitudes of the first and second digital output signals specifically involves:

[0092] The intermediate frequency angular frequency and the low frequency angular frequency are calculated based on the intermediate frequency signal and the low frequency signal, respectively.

[0093] Based on the intermediate frequency angular frequency, the digital quadrature mixing signal is set as the first calculated value, and based on the first calculated value, the first digital output signal and the second digital output signal are respectively converted into a first DC signal and a first signal to be filtered out.

[0094] Based on the low-frequency angular frequency, the digital quadrature mixing signal is set as the second calculated value, and based on the second calculated value, the second digital output signal and the first digital output signal are respectively converted into a second DC signal and a second signal to be filtered out.

[0095] The first signal to be filtered and the second signal to be filtered are filtered out, and the first DC signal and the second DC signal are retained, thereby obtaining the first signal power corresponding to the first DC signal and the second signal power corresponding to the second DC signal.

[0096] As a preferred embodiment, determining the configuration value based on the power of the first signal and the power of the second signal includes:

[0097] The image suppression value is calculated based on the power of the first signal and the power of the second signal, and is used as the configuration value;

[0098] Alternatively, the power of the second signal can be used as a configuration value.

[0099] As a preferred embodiment, the initialization of the mismatch calibration control parameters and the cyclic calculation using the current configuration values ​​update the mismatch calibration control parameters. Then, by comparing the configuration values ​​corresponding to all mismatch calibration control parameters, the final fixed mismatch calibration control parameters are obtained. Specifically:

[0100] Initialize the mismatch calibration control parameters by performing iterative calculations using the current configuration values. During the iterative calculation, the mismatch calibration control parameters are set twice, in both the forward and reverse directions, using the binary search method of the control word. The first and second components corresponding to the current configuration value are calculated for both the forward and reverse directions. Based on the first and second components obtained from the two mismatch calibration control parameter settings, the corresponding mismatch calibration control parameter is selected as the first mismatch calibration control parameter for the next iterative calculation. This process continues until the mismatch calibration control parameters corresponding to all control words are obtained, at which point the parameters are fixed to obtain the final mismatch calibration control parameters. One iteration corresponds to one control word.

[0101] As a preferred embodiment, the mismatch calibration control parameters include phase mismatch calibration control parameters and amplitude mismatch calibration control parameters; the phase mismatch calibration control parameters and the amplitude mismatch calibration control parameters are obtained through separate iterative calculations.

[0102] As a preferred embodiment, the step of compensating and calibrating the output digital signal according to the mismatch calibration control parameters to achieve receiver calibration specifically involves:

[0103] The phase mismatch calibration control parameters and the amplitude mismatch calibration control parameters are used to compensate and calibrate the phase and amplitude of the useful signal after digital signal conversion, and the phase mismatch calibration control parameters and the amplitude mismatch calibration control parameters are used to compensate and calibrate the phase and amplitude of the mirror signal after digital signal conversion, thereby realizing the calibration of the quadrature imbalance of the receiver.

[0104] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working process of the device described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0105] Implementing the above embodiments has the following effects:

[0106] The technical solution of this invention obtains a first digital output signal and a second digital output signal by sampling the radio frequency signal and local oscillator signal input to the receiver, and then obtains the first signal power and the second signal power. After determining the configuration value, the mismatch calibration control parameter is cyclically calculated with the configuration value to obtain the final fixed mismatch calibration control parameter, thereby realizing the calibration of the orthogonal imbalance of the signal. Compared with the prior art, this invention does not require complex calculations and mathematical calculations, has a simple principle, and does not require complex hardware facilities, making it easy to implement. At the same time, the cyclic calculation of the mismatch calibration control parameter and the configuration value can successively approximate a high fault tolerance rate, thereby improving the calibration effect and adjustment accuracy.

[0107] Example 3

[0108] Please see Figure 2 This is an architecture diagram of a receiver. The receiver in this embodiment is used to perform the receiver calibration method as described in Embodiment 1, including a radio frequency signal generator, an input module, an orthogonal compensation module, a sampling module, and a digital algorithm module connected in sequence; wherein, the input terminal of the orthogonal compensation module is also connected to the output terminal of the digital algorithm module.

[0109] The radio frequency signal generator is used to generate radio frequency signals; the input module is used to preprocess the radio frequency signals; the input module includes: a down-conversion mixer, a first receiver intermediate frequency circuit, a second receiver intermediate frequency circuit, a first digital-to-analog converter, and a second digital-to-analog converter.

[0110] The sampling module is used to sample the signal output by the input module; the sampling module includes: a digital quadrature mixer, a first non-recursive filter, and a second non-recursive filter.

[0111] The digital algorithm module is used to quantize and evaluate the sampled signal, and then feed the quantized and evaluated signal back to the orthogonal compensation module.

[0112] The orthogonal compensation module is used to compensate and calibrate the orthogonal imbalance of the input radio frequency signal based on the quantized evaluation signal.

[0113] Furthermore, the input terminal of the downconversion mixer is connected to the output terminal of the radio frequency signal generator, and the input terminal of the downconversion mixer is also connected to the channel for transmitting the local oscillator signal. The output terminals of the downconversion mixer are both connected to the input terminals of the first receiver intermediate frequency circuit and the second receiver intermediate frequency circuit. The output terminals of the first receiver intermediate frequency circuit and the second receiver intermediate frequency circuit are respectively connected to the first digital-to-analog converter and the second digital-to-analog converter. The input terminal of the digital quadrature mixer is connected to the output terminal of the quadrature compensation module. The output terminal of the digital quadrature mixer is respectively connected to the input terminals of the first non-recursive filter and the second non-recursive filter. The output terminals of the first non-recursive filter and the second non-recursive filter are both connected to the input terminal of the digital algorithm module.

[0114] In this embodiment, Mixer is a down-conversion mixer, a module of the RF receiver, used to shift the RF signal to a mid-to-low frequency signal; RXIF is the receiver's intermediate frequency circuit, typically including an active filter and a variable gain amplifier, a module of the RF receiver, used to filter out unwanted signals and amplify useful signals; ADC is a digital-to-analog converter, a module of the RF receiver, used to convert mid-to-low frequency analog signals into digital signals; Quad Mixer is a digital quadrature mixer, a module of the RF receiver, used to convert low-IF signals to zero frequency; Dig Filt is a digital filter, used for anti-aliasing, carrier extraction, etc.; RF SignalGen is an RF signal generator, in RF transceiver chips, this module is usually the transmitter; IQ tune is a quadrature compensation module, used to calibrate the receiver's quadrature imbalance; Algorithm is a digital algorithm module, used for quantization evaluation and feedback control link. RXLO is the local oscillator signal of the receiving channel, the original signal in the RF receiver, used for down-conversion. Wherein, DI... <bit-1:0>And DQ <bit-1:0>The ADC output signal is the original signal in the RF receiver, which is a digital signal. BIT represents the physical number of bits in the ADC. NCO_I and NCO_Q are digital quadrature mixer (DQM) local oscillator signals, which can output different signals according to test requirements. ph_tune <b-1:0>and a_tune <a-1:0>These are the phase mismatch calibration control parameters and amplitude mismatch calibration control parameters. B and A are the control words for the number of control bits, which can be set differently according to different ranges and precision requirements. The highest bit is the sign bit, with 1 indicating a negative value and 0 indicating a positive value; SI <bit-1:0>and SQ <bit-1:0>The sampled signal serves as the data for the algorithm's decision.

[0115] Please see Figure 7 This is a schematic diagram of the IQ tune architecture. The IQ tune quadrature compensation module can compensate for phase and amplitude mismatches, and its design determines the compensation accuracy and range. Here, Iin is the I-channel original signal input (intermediate frequency signal), corresponding to... Figure 2 DI in <bit-1:0>Qin is the original signal input (low-frequency signal) for the Q channel, corresponding to Figure 2 DQ in <bit-1:0>Iout: The output signal after I-channel compensation; Qout: The output signal after Q-channel compensation; where g = 10 (a _ tune*a _ lsb / 20) a_lsb is in dB and represents the minimum gain adjustment precision; while ph = ph_tune * ph_lsb represents the minimum phase adjustment precision. Depending on the actual design, ph_lsb can be in degrees or radians.

[0116] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. In particular, it should be noted that any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention for those skilled in the art.

Claims

1. A calibration method for a receiver, characterized in that, include: By sampling the radio frequency signal and local oscillator signal input to the receiver, the first digital output signal and the second digital output signal after digital signal conversion are calculated. Set up a digital quadrature mixer signal, and obtain the power of the first signal and the power of the second signal based on the signal amplitudes of the first digital output signal and the second digital output signal; Based on the power of the first and second signals, configuration values ​​are determined to initialize mismatch calibration control parameters. The current configuration values ​​are then used for iterative calculations to update the mismatch calibration control parameters. Finally, the configuration values ​​corresponding to all mismatch calibration control parameters are compared to obtain the final fixed mismatch calibration control parameters. Specifically, the mismatch calibration control parameters are initialized, and iterative calculations are performed using the current configuration values. During the iterative calculation, the mismatch calibration control parameters are set twice, in both the forward and reverse directions using the binary search method of the control word. The first and second components corresponding to the current configuration value in the forward direction and the reverse direction are calculated respectively. Based on the first and second components obtained from the two mismatch calibration control parameter settings, the corresponding mismatch calibration control parameter is selected as the first mismatch calibration control parameter for the next iterative calculation. This process continues until the mismatch calibration control parameters corresponding to all control words are obtained, at which point the final mismatch calibration control parameters are fixed. One iteration corresponds to one control word. The output digital signal is compensated and calibrated according to the mismatch calibration control parameters, thereby achieving the calibration of the receiver.

2. The receiver calibration method as described in claim 1, characterized in that, The process of sampling the radio frequency signal and the local oscillator signal input to the receiver to calculate the first and second digital output signals after digital signal conversion is as follows: The receiver receives the radio frequency signal sent to the receiver by the radio frequency signal generator and receives the local oscillator signal through the channel, thereby sampling to obtain the radio frequency signal and the local oscillator signal; The radio frequency signal and the local oscillator signal are mixed by a mixer to obtain a mixed signal. The mixed signal is then filtered out for high frequencies to obtain a mid-to-low frequency signal. The mid-to-low frequency signal includes an intermediate frequency signal and a low frequency signal. Both the intermediate frequency signal and the low frequency signal include a useful signal and a mirror signal. The useful signal and the mirror signal have the same frequency and are 180° out of phase. The frequency of the intermediate frequency signal is higher than that of the low frequency signal. The intermediate frequency signal and the low frequency signal are respectively converted into digital signals to obtain the first digital output signal and the second digital output signal.

3. The receiver calibration method as described in claim 2, characterized in that, The step of setting up a digital quadrature mixer signal and obtaining the power of the first signal and the power of the second signal based on the signal amplitudes of the first and second digital output signals is as follows: The intermediate frequency angular frequency and the low frequency angular frequency are calculated based on the intermediate frequency signal and the low frequency signal, respectively. Based on the intermediate frequency angular frequency, the digital quadrature mixing signal is set as the first calculated value, and based on the first calculated value, the first digital output signal and the second digital output signal are respectively converted into a first DC signal and a first signal to be filtered out. Based on the low-frequency angular frequency, the digital quadrature mixing signal is set as the second calculated value, and based on the second calculated value, the second digital output signal and the first digital output signal are respectively converted into a second DC signal and a second signal to be filtered out. The first signal to be filtered and the second signal to be filtered are filtered out, and the first DC signal and the second DC signal are retained, thereby obtaining the first signal power corresponding to the first DC signal and the second signal power corresponding to the second DC signal.

4. The receiver calibration method as described in claim 3, characterized in that, The step of determining the configuration value based on the power of the first signal and the power of the second signal includes: The image suppression value is calculated based on the power of the first signal and the power of the second signal, and is used as the configuration value; Alternatively, the power of the second signal can be used as a configuration value.

5. The receiver calibration method as described in claim 4, characterized in that, The mismatch calibration control parameters include phase mismatch calibration control parameters and amplitude mismatch calibration control parameters; the phase mismatch calibration control parameters and the amplitude mismatch calibration control parameters are obtained through separate iterative calculations.

6. The receiver calibration method as described in claim 5, characterized in that, The step of compensating and calibrating the output digital signal according to the mismatch calibration control parameters to calibrate the receiver is as follows: The phase mismatch calibration control parameters and the amplitude mismatch calibration control parameters are used to perform phase and amplitude compensation calibration on the intermediate frequency signal after digital signal conversion, and the phase mismatch calibration control parameters and the amplitude mismatch calibration control parameters are used to perform phase and amplitude compensation calibration on the low frequency signal after digital signal conversion, thereby realizing the calibration of the receiver's quadrature imbalance.

7. A calibration device for a receiver, characterized in that, include: Sampling module, quantization module, decision loop module, and calibration module; The sampling module is used to calculate the first digital output signal and the second digital output signal after digital signal conversion by sampling the radio frequency signal and the local oscillator signal input to the receiver. The quantization module is used to set the digital quadrature mixing signal and obtain the power of the first signal and the power of the second signal based on the signal amplitudes of the first digital output signal and the second digital output signal. The determination loop module is used to determine the configuration value based on the power of the first signal and the power of the second signal, so as to initialize the mismatch calibration control parameters, and perform loop calculation using the current configuration value to update the mismatch calibration control parameters. Then, after comparing the configuration values ​​corresponding to all mismatch calibration control parameters, the final fixed mismatch calibration control parameters are obtained. Specifically, the mismatch calibration control parameters are initialized, and loop calculation is performed using the current configuration value. During the loop calculation, the mismatch calibration control parameters are set twice using the bisection method of the control word in both the positive and negative directions. The first and second components corresponding to the current configuration value in the positive direction and the first and second components corresponding to the current configuration value in the negative direction are calculated respectively. Based on the first and second components obtained from the two mismatch calibration control parameter settings, the corresponding mismatch calibration control parameter is selected as the first mismatch calibration control parameter for the next loop calculation. This process continues until the mismatch calibration control parameters corresponding to all control words are obtained, and then the final mismatch calibration control parameters are fixed. One loop corresponds to one control word. The calibration module is used to compensate and calibrate the output digital signal according to the mismatch calibration control parameters, thereby calibrating the receiver.

8. A receiver, characterized in that, The calibration method for the receiver as described in any one of claims 1-6 includes a radio frequency signal generator, an input module, an orthogonal compensation module, a sampling module, and a digital algorithm module connected in sequence; wherein the input terminal of the orthogonal compensation module is also connected to the output terminal of the digital algorithm module; The radio frequency signal generator is used to generate radio frequency signals; the input module is used to preprocess the radio frequency signals. The sampling module is used to sample the signal output by the input module; The digital algorithm module is used to quantize and evaluate the sampled signal, and then feed the quantized and evaluated signal back to the orthogonal compensation module. The orthogonal compensation module is used to compensate and calibrate the orthogonal imbalance of the input radio frequency signal based on the quantized evaluation signal.

9. A receiver as described in claim 8, characterized in that, The input module includes: a downconverter mixer, a first receiver intermediate frequency circuit, a second receiver intermediate frequency circuit, a first digital-to-analog converter, and a second digital-to-analog converter; the sampling module includes: a digital quadrature mixer, a first non-recursive filter, and a second non-recursive filter. The input terminal of the downconversion mixer is connected to the output terminal of the radio frequency signal generator. The input terminal of the downconversion mixer is also connected to the channel for transmitting the local oscillator signal. The output terminals of the downconversion mixer are both connected to the input terminals of the first receiver intermediate frequency circuit and the second receiver intermediate frequency circuit. The output terminals of the first receiver intermediate frequency circuit and the second receiver intermediate frequency circuit are respectively connected to the first digital-to-analog converter and the second digital-to-analog converter. The input terminal of the digital quadrature mixer is connected to the output terminal of the quadrature compensation module. The output terminal of the digital quadrature mixer is respectively connected to the input terminals of the first non-recursive filter and the second non-recursive filter. The output terminals of the first non-recursive filter and the second non-recursive filter are both connected to the input terminal of the digital algorithm module.

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