9 results about "Phase imbalance" patented technology

This invention discloses a broadband oscillation discrimination system and method based on a positive-sequence instantaneous power algorithm, comprising: an A / D sampling module for acquiring an analog signal and obtaining a synchronously sampled digital signal based on the analog signal; an FPGA module for calculating the positive-sequence instantaneous power based on the synchronously sampled digital signal and obtaining a second calculation result; and a CPU module for obtaining a broadband oscillation discrimination result based on the second calculation result. The FPGA module is connected to the A / D sampling module and the CPU module via a parallel data bus. Using positive-sequence instantaneous power to discriminate broadband oscillations can filter out the second harmonic component caused by three-phase imbalance, and also filter out new frequency components caused by this component superimposed on the broadband oscillation instantaneous power.

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.

A radar device may identify a peak in an integrated range-velocity map. The peak may indicate one or more targets in the integrated range-velocity map and being associated with a range-velocity bin index. The radar device may extract, based on the range-velocity bin index associated with the peak, an actual signal vector from a plurality of range-velocity maps. Each range-velocity map in the plurality of range-velocity maps may correspond to a respective radar channel from a plurality of radar channels. The radar device may determine an estimated target signal vector based on the actual signal vector and a first estimated imbalance vector. The radar device may determine a second estimated imbalance vector based on the actual signal vector, the estimated target signal vector, and an error vector. The radar device may perform an action, associated with the plurality of radar channels, based on the second estimated imbalance vector.

The invention discloses an IQ imbalance estimation and compensation method based on a constellation diagram, and belongs to the technical field of wireless communication signal processing. The method comprises the following steps: preprocessing a received signal, including frequency offset compensation, power normalization, matched filtering, symbol synchronization and phase correction; extracting constellation points of the demodulated signals, and mapping the constellation points to ideal constellation points; respectively constructing an amplitude error function and a phase error function, and estimating an IQ amplitude imbalance factor and a phase imbalance factor with high precision by using a least square method; and finally, compensating a received signal by using the estimated factor, and correcting a distorted constellation diagram. The core of the method is that low-complexity and high-precision IQ imbalance blind estimation and compensation can be realized only by using demodulated constellation point information without depending on a training sequence or pilot frequency, the bit error rate of the system is effectively reduced, and the method is particularly suitable for burst communication and high-order modulation systems.

The invention discloses an online monitoring method and system for IQ damage of a feed-forward type full-blind coherent optical receiver, and belongs to the technical field of optical fiber communication, coherent detection and digital signal processing. The method aims to solve the problems of low spectrum efficiency and high calculation complexity caused by dependence on pilot frequency or an iterative feedback process in the existing on-line monitoring technology. The method is characterized by comprising the following steps of: performing fast Fourier transform on a received signal; screening out monitoring frequency points which can be used for damage estimation in a protection band by utilizing local oscillation frequency deviation and signal protection band information; respectively calculating a first estimation parameter and a second estimation parameter based on the frequency domain data of the monitoring frequency point; and directly obtaining an IQ amplitude imbalance estimation value through the first estimation parameter, carrying out linear fitting on the second estimation parameter, and respectively extracting IQ relative time delay and phase imbalance estimation values from the slope and the intercept of a fitting straight line. According to the invention, non-iterative feed-forward online monitoring without a training sequence is realized, and the complexity and power consumption of the system are reduced.

This invention discloses a short-range microwave ranging method based on I / Q signal correction, belonging to the field of microwave ranging and signal processing technology. Addressing the issues of DC bias in I / Q signals caused by receiver non-ideals and clutter reflections, as well as trajectory distortion and demodulation errors caused by unknown amplitude modulation and I / Q amplitude-phase imbalance in microwave phase difference ranging, a correction process combining DC bias estimation and spectral correction is proposed. The method includes: constructing a ratio differential signal incorporating DC bias parameters; establishing an objective function based on elliptic fitting residuals and solving for the DC bias using an optimization algorithm; performing demodulation reconstruction and frequency domain analysis after DC compensation to solve for the amplitude-phase imbalance parameters; correcting the I / Q signals accordingly; and obtaining the target distance change through arctangent demodulation and phase expansion. This application can achieve parameter estimation under any unknown amplitude modulation conditions, improving the accuracy and robustness of short-range ranging.

1. Name of the product in this design: Microcomputer Motor Protector (YHDB). 2. Application of this design: It is used for multiple protections of motors against overload, short circuit, phase loss and phase imbalance, overvoltage, undervoltage and leakage. 3. The key design features of this product are the combination of shape and color. 4. The image or photograph that best illustrates the design's key points: a 3D model. 5. The design for which protection is sought includes color.

The embodiment of the invention discloses a filter synchronization signal extraction and phase locking device and method, a storage medium and a terminal, and the device comprises a signal source module which is used for determining a two-phase voltage component according to a three-phase power grid voltage signal; the filtering feedback network is used for filtering the two-phase voltage component according to the corresponding condition of the input frequency and determining a single-frequency waveform component under the current input frequency; the self-adaptive wave trapping module comprises a plurality of self-adaptive wave traps connected in parallel, and the self-adaptive wave traps are respectively used for receiving single-frequency waveform components corresponding to the input frequencies of the self-adaptive wave traps and determining orthogonal signal components under the current input frequency; the synchronous signal extraction module is used for extracting a positive sequence component and a negative sequence component of the orthogonal signal component; and the phase locking module is used for performing phase locking according to the positive sequence component. According to the method, the positive sequence component and the negative sequence component under different input frequencies can be accurately extracted, and the positive sequence component and the negative sequence component can be accurately tracked under severe conditions such as three-phase imbalance of power grid voltage.

The invention relates to the field of blade tip clearance measurement, in particular to a compensation type displacement high-precision microwave measurement method, by providing a new compensation technology, namely radar orthogonal signal equalization, the radar orthogonal signal equalization method firstly provides a mirror image congruence concept in an I / Q channel self-convolution track space, and the compensation type displacement high-precision microwave measurement method is provided. And a new view angle is provided for compensating amplitude and phase imbalance. The method comprises the following steps of: firstly, estimating a direct-current offset parameter by analyzing accumulated energy of a orthogonal channel; then, based on the mirror image congruence characteristic, an objective function used for compensating parameter estimation is formulated, amplitude-phase imbalance correction is achieved through multiple regression, the parameter estimation performance of the radar orthogonal signal equalization method has robustness for nonlinear modulation and high-order harmonics, and the method is superior to an existing method; and errors and nonlinearity of blade tip clearance measurement are significantly reduced.