74 results about "IQ imbalance" patented technology

The invention discloses an IQ imbalance blind calibration method and an IQ modulation demodulator, and the method comprises the steps: determining a regularity judgment condition based on the second-order statistical characteristics of a complex signal under an ideal condition; building an IQ imbalance mathematical model to determine a compensation mode; obtaining a compensation coefficient formula based on the compensation mode, the regularity judgment condition and the step diagonal matrix; substituting the complex signal into a compensation coefficient formula to obtain a high-order LMS dual-channel algorithm model; a nonlinear step size error model is introduced into a high-order LMS double-channel algorithm model. The invention provides a frequency-related square difference operation variable step size IQ imbalance dual-channel high-order blind compensation filtering algorithm without any prior information. Algorithm parameters are adjusted according to signal mismatch caused by phase mismatch and amplitude imbalance of input signals, so that the signals keep an ideal orthogonal relation.

The invention belongs to the technical field of wireless communication, and particularly relates to a receiving and transmitting end IQ imbalance estimation method based on constant modulus characteristics. The method is used for a terahertz CE-OFDM communication perception integrated system, and the IQ imbalance parameter is solved by establishing an optimization problem based on the constant modulus characteristic by using a signal received by a receiver, so that digital domain compensation in the receiver is facilitated, and a feedback loop and a training process of a traditional method are not needed.

A method and apparatus for compensating an in- and quadrature-(IQ) imbalance are disclosed. The method and apparatus for compensating an in- and quadrature-(IQ) imbalance provide a technique for compensating a signal distortion caused by imperfect element features and various noises on a transmission link in terahertz wireless communication and improving transmission performance.

The present invention discloses a zero-IF receiving array IQ imbalance beam-level compensation method, comprising: obtaining a radio frequency signal received by each array element; obtaining M intermediate frequency analog signals; obtaining M baseband analog in-phase signals and M baseband analog quadrature signals; performing A / D sampling on the M baseband analog in-phase signals and the M baseband analog quadrature signals respectively to obtain M baseband digital complex signals; obtaining M receiving channel amplitude and phase error compensation values; performing channel amplitude and phase error compensation and beam weighting compensation on the M baseband digital complex signals of the digital array, and summing the values to obtain a beamformed output complex signal; and utilizing the circular characteristics of the received baseband digital complex signals to estimate and compensate for the IQ imbalance error after beamforming to obtain a final baseband digital complex signal of the digital array. The present invention has the advantages of providing a multi-channel IQ imbalance compensation method that does not require channel-by-channel estimation and compensation for IQ imbalance errors and protects the circular characteristics of communication signals from being destroyed.

The invention discloses a TFDM-PON system correction method and device, and the method comprises the steps: an OLT receives a dual-polarization signal transmitted by an ONU based on time division multiplexing or time-frequency division multiplexing, the dual-polarization signal comprises a target signal sequence corresponding to X / Y polarization, and the target signal sequence is an IQ period complex signal, and an I path and a Q path of the IQ period complex signal are single-tone signals of a first frequency and a second frequency respectively; target parameters including target transmitting and receiving end frequency deviation, IQ time delays of a target transmitting end and a target receiving end and target power deviation among ONUs are calculated based on Fourier transform and frequency domain symmetry of the dual-polarization signals, so that the ONUs carry out frequency, time delay and power correction according to the target parameters. Subcarrier crosstalk caused by frequency offset in TDM uplink burst transmission, mirror image crosstalk caused by IQ imbalance and performance degradation caused by power imbalance between subcarriers are eliminated, the bit error rate is reduced, and the system robustness is improved.

A radio communication method according to an embodiment is a radio communication method for transmitting a signal from a transmitter to a receiver using a single carrier, in which the transmitter generates two or more training signals using a symmetric subcarrier at the time of training to perform an OFDM modulation, and shapes a spectrum of each of the OFDM-modulated training signals to be close to a single carrier spectrum, and in which the receiver adjusts the timing of two or more training signals, using a single carrier time domain correlation sequence at the time of training, estimates a channel response and an IQ imbalance from the two or more training signals whose timing is adjusted, compensates for the estimated IQ imbalance, and demodulates the compensated signal.

The present invention discloses a method and device for demodulating and analyzing large Doppler frequency shift (OTFS) satellite communications, belonging to the field of satellite communications. The device includes a data acquisition unit, an IQ imbalance calculation unit, an amplitude error calculation unit, a continuous phase signal generation unit, a convolution detection frame header determination unit, two guard slot removal units, two receive reference signal acquisition units, a sampling phase error acquisition unit, two theoretical demodulation reference signal generation units, a channel model extraction unit, a Doppler frequency error calculation unit, a Doppler frequency error elimination unit, a phase error calculation unit, a Doppler phase error elimination unit, a channel estimation unit, an interpolation and smoothing unit, a channel error elimination unit, a Wigner transform unit, a symplectic finite Fourier transform unit, a digital modulation and demodulation unit, and an error vector magnitude (EVM) calculation unit. The present invention can achieve high-precision demodulation and analysis of large Doppler frequency shift (OTFS) orthogonal time-frequency-space modulation (6G) satellite communication signals.

The invention provides a zero intermediate frequency transceiver receiving channel IQ imbalance calibration method, and relates to the field of radio frequency transceiver calibration. In the method, a single-tone calibration signal generator generates a single-tone signal in a self-calibration process; the dual-tone excitation signal synthesizer is used for generating dual-tone excitation signals in the self-calibration process; the radio frequency switch is communicated with the sending channel and the receiving channel in the calibration process, and an excitation signal sent by the sending channel is looped back to the receiving channel; the error extraction unit is used for extracting an IQ error and calculating a compensation coefficient; and the error compensation unit is used for compensating the link signal. According to the method, a dual-tone test signal is generated by a sending channel, and IQ unbalance is extracted and compensated in a receiving channel according to an algorithm provided by the invention. According to the method, a calibration environment does not need to be set up by external equipment, self-calibration of the chip can be realized, and the calibration cost of a single chip can be effectively reduced.

The present application discloses a dynamic power consumption management system, comprising: an equalization algorithm circuit, a carrier recovery algorithm circuit, and an IQ imbalance algorithm circuit; an equalization algorithm coefficient update circuit connected to an output end of the carrier recovery algorithm circuit and configured to provide equalization algorithm update coefficients to the equalization algorithm circuit; a carrier recovery frequency offset and phase noise calculation circuit connected to an output end of the equalization algorithm circuit and configured to provide carrier recovery frequency offset and phase noise coefficients to the carrier recovery algorithm circuit; an IQ imbalance algorithm coefficient update circuit connected to an output end of the IQ imbalance algorithm circuit and configured to provide IQ imbalance algorithm coefficients to the IQ imbalance algorithm circuit; a signal-to-noise ratio reporting circuit connected to an output end of the IQ imbalance algorithm circuit and configured to acquire a signal-to-noise ratio of the entire system; and a management circuit configured to determine the equalization algorithm update coefficients, the carrier recovery frequency offset and phase noise coefficients, and the IQ imbalance algorithm coefficients based on the signal-to-noise ratio. The present application can reduce the power consumption of chips.

This disclosure provides systems, methods and apparatus, including computer programs encoded on computer storage media, for dedicated pilot signals associated with radio frequency impairment compensation. In some aspects, a user equipment (UE) and a network entity may support a signaling mechanism according to which the UE may measure and report, to the network entity, an imbalance between an in-phase (I) component and a quadrature (Q) component of a modulated signal. For example, the UE may request the network entity to transmit an out-of-band pilot signal to enable frequency domain residual side band (FDRSB) estimation at the UE and the UE may transmit measurement information associated with the IQ imbalance or the FDRSB estimation to the network entity. The network entity may receive the measurement information and compensate or correct signaling in accordance with the received measurement information.

This application discloses an IQ imbalance compensation method for WiFi broadband transmitting and receiving paths and application thereof. This application relates to the field of digital signal processing. The method comprises: inputting IQ signals into a frequency-related IQ imbalance compensation device FD-IQMC; the FD-IQMC device first performing frequency-independent overall compensation on IQ imbalance by means of a frequency-independent IQ imbalance compensation module FI-iqmc, and then selecting one signal from the IQ signals and inputting same into a Frac-delay filter and an Amp-FIR filter so as to respectively perform phase and amplitude compensation of frequency-selectivity; and inputting another signal into a delay module to be time-aligned with the selected signal.

The present disclosure provides a method, apparatus, and device for compensating for carrier phase and IQ imbalance of a communication receiver, which can be applied to the field of communication signal processing technology. The method includes: sampling a received signal of a communication receiver to obtain a received signal sequence, wherein the communication receiver includes a transmitter and a receiver, and the receiver processes the transmitted signal from the transmitter to obtain a received signal; calculating the expectation and covariance matrices of the received signal sequence, and constructing a likelihood function corresponding to the received signal sequence based on the expectation and covariance matrices; derivatizing the logarithmic function of the likelihood function to obtain a set of estimation equations corresponding to multiple parameters to be estimated; iteratively solving the set of estimation equations according to a predetermined number of iterations to obtain multiple target estimation parameters corresponding to the multiple parameters to be estimated; and compensating the received signal sequence based on the target estimation parameters to obtain a target signal sequence.

The invention discloses a broadband image rejection method based on combination of an LS algorithm and an MP model, and belongs to the field of communication. According to the method, a method of combining a least square algorithm (LS algorithm) and a memory polynomial model (MP) describing nonlinear response is adopted, and local oscillator leakage, mirror image frequency distortion and in-band uneven distortion in a zero intermediate frequency transceiver passband are effectively compensated; in-band uneven distortion is effectively suppressed, the suppression effect on mirror image frequency distortion is better, and the applicable frequency band range is wider; the method not only can be used for independently carrying out image rejection compensation on a zero-intermediate-frequency transmitter or receiver, but also can be used for carrying out closed-loop adaptive image rejection compensation on a zero-intermediate-frequency transceiver, so that the problem that two IQ imbalance distortions of the transmitter and the receiver are aliasing together and cannot be distinguished and corrected when no reference instrument exists is solved; and a technical support is provided for a more ideal test channel environment of the zero-intermediate-frequency signal transceiver.

The application discloses a wideband quadrature calibration method and device of a radio frequency transceiver and the radio frequency transceiver, relates to the technical field of radio frequency transceivers, and comprises the following steps: controlling injection of a preset in-band single-tone test signal and a preset local oscillator signal, acquiring an I / Q path in-band power value, calculating a difference value, and compensating the frequency-independent IQ gain imbalance in the digital domain through digital gain compensation. Controlling injection of a preset attenuation point test signal and a local oscillator signal, acquiring an I / Q path cutoff frequency point power value, and combining the I / Q path in-band power value to determine the double-frequency point power difference of the I / Q path. According to the deviation of the double-frequency point power difference of the I / Q path and a target attenuation amount, the cutoff frequency of the I / Q path filter is adjusted respectively, and the frequency-dependent IQ imbalance is calibrated in the analog domain. The application replaces the quadrature calibration signal with a single-tone signal for testing, expands the application scenario, simplifies the wideband IQ balance calculation in the digital domain, and reduces the hardware resource consumption and time delay.

The present disclosure provides a signal processing method, comprising: determining a first parameter set of a second signal based on a first signal; determining a second parameter set of a third signal based on the first signal, the third signal being a feedback signal of the first signal at a second phase shift angle, the second phase shift angle satisfying a first preset condition; determining a first feedback mirror image compensation coefficient and a second feedback mirror image compensation coefficient based on the first parameter set and the second parameter set; and determining a transmission mirror image compensation coefficient based on the first feedback mirror image compensation coefficient, the second feedback mirror image compensation coefficient, and the second signal or the third signal. The method of the present disclosure determines the first parameter set and the second parameter set through two different phase shift angles, and then determines the feedback mirror image compensation coefficient and the transmission mirror image compensation coefficient based on the first parameter set and the second parameter set, thereby improving the convenience and accuracy of the compensation coefficient determination, and without causing changes in the inherent IQ imbalance characteristics.

The invention provides a signal processing method, which comprises the steps of determining a first parameter set of a second signal based on a first signal; based on the first signal, a second parameter set of a third signal is determined, the third signal is a feedback signal of the first signal at a second phase shift angle, and the second phase shift angle meets a first preset condition; determining a first feedback mirror image compensation coefficient and a second feedback mirror image compensation coefficient based on the first parameter set and the second parameter set; a transmit image compensation coefficient is determined based on the first feedback image compensation coefficient, the second feedback image compensation coefficient, and the second signal or the third signal. According to the method disclosed by the invention, the first parameter set and the second parameter set are determined through the two different phase shift angles, and then the feedback mirror image compensation coefficient and the emission mirror image compensation coefficient are determined based on the first parameter set and the second parameter set, so that the convenience and accuracy of compensation coefficient determination are improved, and the change of inherent IQ imbalance characteristics is not caused.

An apparatus and method to measure nonlinear system noises may include a processor to generate a bilateral notch signal, a unilateral notch signal and a multi-tone signal; to measure power of an additive Gaussian white noise of a nonlinear system by using the multi-tone signal; to measure a first power-to-noise ratio of the nonlinear system by using the bilateral notch signal; to measure a second power-to-noise ratio of the nonlinear system by using the unilateral notch signal. The processor is to calculate a nonlinear power-to-noise ratio of the nonlinear system and a power-to-noise ratio introduced by IQ imbalance according to the power of the additive Gaussian white noise, the first power-to-noise ratio and the second power-to-noise ratio.

The invention relates to an IQ imbalance estimation value obtaining method based on single-tone detection, and the method comprises the steps: receiving a fixed-frequency single-tone signal through a zero-intermediate-frequency receiver, and obtaining the basic parameters of the fixed-frequency single-tone signal; performing first processing on the fixed-frequency single-tone signal to obtain a corresponding digital baseband single-tone signal; performing second processing on the digital baseband single-tone signal to obtain the digital baseband single-tone signal after compensation of the received direct current bias; performing truncation processing on the digital baseband single-tone signal after compensation of the received direct current bias to obtain a truncated digital baseband single-tone signal; and obtaining I-path and Q-path frequency domain signals of the truncated digital baseband single-tone signal according to the truncated digital baseband single-tone signal, and obtaining an IQ phase imbalance estimated value and an IQ amplitude imbalance estimated value according to the I-path and Q-path frequency domain signals. The method provided by the invention solves the problems of low accuracy and high complexity of the IQ imbalance estimation value in the prior art.

A TFDM-PON system correction method and device, including OLT receiving ONU based on time division multiplexing or time-frequency division multiplexing sends double polarization signal, it includes target signal sequence corresponding with X / Y polarization, and target signal sequence is IQ period complex signal and its I road and Q road are single tone signal of first frequency and second frequency respectively;Based on the Fourier transform of double polarization signal and frequency domain symmetry, calculate target parameters including target transceiver frequency offset, target transmitting terminal, receiving terminal IQ delay and target power deviation between each ONU, make ONU correct frequency, delay and power according to target parameters, eliminate subcarrier crosstalk caused by frequency offset in TFDM uplink burst transmission, image crosstalk caused by IQ imbalance and performance degradation caused by subcarrier power imbalance, reduce bit error rate, improve system robustness.

The invention provides a closed-loop calibration system and method for IQ imbalance, and relates to the technical field of communication, the system comprises a digital transmitter, a power amplifier, a low noise amplifier and a digital receiver which are connected in sequence, and further comprises a digital correlator, a resolving unit, a phase controller and an IQ imbalance compensator; and the power amplifier is connected with the low-noise amplifier through a coupling loop. According to the invention, the analog phase and the digital phase of the loop are adjusted through the phase controller, and the simultaneous calibration of IQ imbalance in the digital transmitter and the digital receiver is realized by combining the four cross-correlation operation of the digital correlator and the parameter joint estimation of the calculation unit without a phase shift module. Phase switching can be realized by using an existing tuning capacitor of a power amplifier or a low-noise amplifier, the design is simple, and a coupling loop is close to an antenna port, so that the calibration precision is not easily influenced by interference and radiation of an internal radio frequency module; and meanwhile, hardware is easy to realize, the complexity is low, the estimation precision is high and the stability is strong.

The present invention provides a method and system for obtaining a compensation value for carrier leakage. The carrier leakage ranges of the I channel and the Q channel are set, and the compensation value of the training signal transmitted by the transmitting module is determined according to the carrier leakage ranges of the I channel and the Q channel. The receiving module receives the carrier leakage signal that appears when the training signal is transmitted. The receiving frequency of the receiving module and the transmitting frequency of the transmitting module differ by a first preset number of sub-carrier intervals. The carrier leakage signal is converted into a single-tone signal, and the power value of the single-tone signal is calculated. The compensation value is selected according to the power value, and the carrier leakage ranges of the I channel and the Q channel are updated according to the selected compensation value. The iteration is performed until the length of the carrier leakage range is less than a certain value. The deviation between the receiving frequency and the transmitting frequency is set to an integer multiple of the sub-carrier interval, and the influence of the receiver IQ imbalance on the carrier leakage is eliminated, so as to obtain a more accurate estimation of the carrier leakage.

The present invention discloses a method, system and medium for IQ imbalance correction of a zero-IF architecture transceiver; relates to the technical field; on the basis of traditional imbalance correction techniques, improvements are made in the method, making full use of the characteristics of the zero-IF architecture itself, and IQ imbalance correction is carried out at the receiving end and the transmitting end respectively. At the receiving end, the imbalance coefficient is calculated according to the received baseband data and the imbalance coefficient model, and the received baseband data is corrected with the imbalance coefficient; at the transmitting end, a first transmitted baseband signal and a second transmitted baseband signal are respectively configured at the transmitting end, the first characteristic quantity and the second characteristic quantity are obtained, and the first characteristic quantity and the second characteristic quantity are substituted into the correction coefficient model to calculate the correction coefficient to realize the correction of the original baseband signal. Through simple data acquisition and calculation, the compensation of the digital baseband signal is realized, thereby suppressing the amplitude of the image signal.

The invention discloses an individual identification method for communication radiation sources based on receiver distortion compensation, including: constructing a reference receiver and a receiver to be compensated; training a compensation module according to signals of the two to learn distortion differences; performing preliminary compensation on signals of the receiver to be compensated; performing residual IQ imbalance compensation on the preliminarily compensated signals; and completing individual identification of communication radiation sources based on the compensated signals. The method effectively eliminates hardware distortion of receivers and improves the accuracy and robustness of identification in cross-receiver scenarios.

The invention provides an IQ imbalance calibration method and system for an ultra-wideband system, an electronic device, a computer storage medium and a program product. The method comprises the following steps: selecting a plurality of frequency points in a system bandwidth; for each frequency point, respectively generating a first source signal and a second source signal at a transmitting end and performing phase rotation to obtain a first calibration signal and a second calibration signal with a fixed phase difference; respectively sending the first calibration signal and the second calibration signal from the transmitting end to the receiving end through a feedback loop; receiving and processing the first and second calibration signals at a receiving end, respectively, to obtain first and second observation signals; and correlating the first and second observation signals with the first and second source signals, respectively, to obtain first and second correlation coefficients; estimating an actual fixed phase difference based on the first and second correlation coefficients of the plurality of frequency points; determining an IQ imbalance coefficient of each frequency point based on the actual fixed phase difference; and compensating the IQ imbalance of the system based on the IQ imbalance coefficients of the plurality of frequency points.

The application relates to the technical field of wireless communication and digital signal processing, and discloses a modulation signal transceiving system and method based on IQ domain maximum ratio combining, specifically, a Delta-Sigma modulation technology is used at a transmitting end to convert a high-order modulation signal into a low-bit stream, and the precision requirement of a data converter is significantly reduced; an IQ domain maximum ratio combining mechanism is introduced at a receiving end, after IQ imbalance is corrected through digital preprocessing, dynamic weighted combining is carried out according to the signal-to-noise ratios of all receiving branches, and diversity gain is effectively utilized. Through the collaborative design of the transmitting end and the receiving end, the signal-to-noise ratio of the combined signal can be significantly improved under the conditions of high frequency and long distance transmission, the influence of channel fading and noise can be effectively inhibited, and thus the demodulation reliability and the overall robustness of the system can be greatly enhanced on the premise that the noise shaping characteristics of the Delta-Sigma modulation signal are not damaged.

The invention discloses an IQ imbalance compensation method, an IQ imbalance compensation device and communication equipment. The IQ imbalance compensation method comprises the following steps: determining a second-order difference hopping subcarrier set S of a pilot signal; # imgabs1 # when the target function # imgabs0 # is minimum is calculated as an IQ imbalance compensation coefficient # imgabs2 #, # imgabs3 # imgabs4 # imgabs5 # YP, k + i and YP, N-(k + i) are frequency domain receiving signals on the (k + i) th subcarrier and the N-(k + i) th subcarrier respectively, XP and k + i are frequency domain transmitting pilot signals on the (k + i) th subcarrier, N is the size of IDFT, and i =-1, 0 or 1, alphagt; 0; and performing IQ imbalance compensation on the received signal by using the IQ imbalance compensation coefficient # imgabs6 #. According to the invention, the IQ imbalance generated by the transmitter and the receiver can be compensated, and the performance of the receiver is improved.

The application relates to the technical field of optical fiber communication, and provides an IQ imbalance estimation method and system, which comprises the following steps: extracting a pair of IQ sampling data of a current clock cycle according to a preset rule; combining phase-compensated IQ sampling data of a previous clock cycle to perform amplitude compensation on the IQ sampling data of the current clock cycle, so as to obtain amplitude-compensated IQ sampling data of the current clock cycle and an amplitude compensation estimation value; combining the amplitude-compensated IQ sampling data of the current clock cycle and the phase-compensated IQ sampling data of the previous clock cycle to perform phase compensation on the IQ sampling data of the current clock cycle, so as to obtain phase-compensated IQ sampling data of the current clock cycle and a phase compensation estimation value; and performing compensation correction on input IQ data according to the amplitude compensation estimation value and the phase compensation estimation value. The amplitude compensation estimation value and the phase compensation estimation value are iteratively accumulated by calculating the amplitude compensation estimation value and the phase compensation estimation value through each pair of IQ sampling data, so that the requirement for hardware is reduced.

The embodiment of the invention provides an IQ imbalance calibration method and device, a signal transmitter and a zero intermediate frequency transceiver, and the method comprises the steps: obtaining a reference baseband signal and a radio frequency signal outputted by an IQ modulation channel based on the reference baseband signal, and converting the radio frequency signal into a modulation baseband signal; reconstructing the modulation baseband signal to generate a baseband feedback signal used for representing distortion of the IQ modulation channel; based on the reference baseband signal and the baseband feedback signal, obtaining a pre-distortion parameter for compensating IQ imbalance; performing pre-distortion processing on the reference baseband signal by using the pre-distortion parameter to generate a baseband pre-distortion signal; and based on the baseband pre-distortion signal, performing imbalance calibration on an IQ modulation channel. As the IQ modulation channel is calibrated, the image rejection ratio and error vector amplitude performance of the output signal can be improved, and the calibration precision of the IQ modulation channel is improved.

The invention discloses an IQ imbalance calibration method and system. The method comprises pre-calibration and fine calibration. During pre-calibration, firstly, M frequency points are selected in a sectional mode, narrow-band calibration is carried out, correlation factors of amplitude imbalance errors and phase imbalance errors of the multiple frequency points are obtained, interpolation fitting is carried out on zero frequency points, and frequency response characteristics in the whole bandwidth are obtained. On the basis, a solution equation is constructed to calculate a filter coefficient, and a filter is designed to compensate the IQ imbalance error. During fine calibration, based on the least square method, the compensation coefficient of the filter is calculated in a real-time and self-adaptive manner, whether iteration is updated or not is judged, iterative filtering is carried out to enhance the stability of the system, and the problem of calibration performance deterioration caused by environmental factors such as temperature change is effectively solved. Compared with traditional narrowband calibration, the calibration system combining pre-calibration and fine calibration has a calibration effect on receiver large-bandwidth IQ imbalance, the adaptive capacity of the calibration system to environment temperature changes is enhanced, and the calibration precision and robustness are improved.

This invention discloses a method and system for suppressing distributed co-channel interference in a region-coexisting environment. The method includes: a desired signal node generating a desired signal and transmitting it through an antenna; distributed interference nodes generating interference signals and transmitting them through antennas; authorized receiving nodes receiving and processing the signals to obtain the down-converted received signal; converting the received distributed interference signal into real and imaginary parts, expanding it with respect to time error and residual frequency offset to obtain the interference signal expression after expansion with time error and residual frequency offset; merging the time-invariant coefficients before the real and imaginary parts of the interference signal into one term to obtain the reconstruction coefficient expression of the distributed interference; estimating the coefficients of the distributed interference suppression system model; reconstructing the interference signal; performing distributed interference suppression; and obtaining the desired signal. This invention achieves the reconstruction and suppression of distributed interference signals under constraints of time error, frequency offset, and IQ imbalance.