6 results about "Polyphase decomposition" patented technology

The invention discloses an interpolation filter design method based on fuel measurement signal multi-phase decomposition, and belongs to the technical field of filter digital signal processing. According to the method, the cut-off frequency and transition band characteristics of an interpolation filter are optimized through the multi-sampling-rate conversion theory and the multi-phase decomposition technology, and filtering parameters are dynamically adjusted in combination with an adaptive algorithm; the high-precision reconstruction of a fuel measurement signal is realized; the core is that a rear digital low-pass filter is designed, a frequency spectrum compression and expansion technology is used for inhibiting an aliasing effect, and calculation efficiency is improved through a multiphase decomposition structure; the method is especially suitable for an aviation fuel measurement system, can balance data redundancy and signal fidelity under different sampling rates, and significantly improves the measurement precision and the system stability.

This invention relates to the field of digital signal processing technology and discloses a low-complexity, high-precision delay method based on polyphase filter interpolation, comprising: S1 designing a prototype low-pass filter; S2 performing polyphase decomposition on the interpolated filter, decomposing it into I-phase; S3 decomposing the fractional delay requirement of the input signal, with the integer part implemented through sampling period delay and the fractional part implemented through a fractional delay filter; S4 storing the coefficients of the I-phase filter as a coefficient array, and determining the delay interval of the virtual branch according to the input fractional delay parameters; S5 using polynomial interpolation to fit the filter coefficients of the virtual branch from the coefficient array, configuring them into an FIR filter to form a fractional delay filter; S6 designing the fractional delay filter as a high-speed parallel filter structure, converting serial computation into L-way parallel computation. This invention achieves high-precision variable fractional delay control with a low-complexity, low-computational-load configurable filter structure.

This invention provides an interpolation FIR filter optimization method, apparatus, and electronic device, comprising: decomposing the interpolation FIR filter into multiple phase sub-filters; performing zero-placing on the original coefficient length according to the relationship between the original coefficient length and the interpolation ratio to obtain a target coefficient length; performing polyphase decomposition on the target coefficient length and performing addition and subtraction operations to obtain a symmetrical combination of coefficients with a symmetrical structure; and performing symmetrical folding and restoration processing on the symmetrical combination of coefficients to obtain the filtering result. By performing zero-placing on the coefficient length to meet the coefficient symmetry requirements after polyphase decomposition, not only can the number of interpolation filter multiplication operations be effectively reduced by half, but it can also adapt to arbitrary interpolation ratios and coefficient lengths; by performing restoration processing after obtaining the output signal of each phase sub-filter, the coefficient phase information can be efficiently restored, ensuring the correctness of the filtering result, thus solving the problem of how to reduce the number of FIR filter multiplication operations using a polyphase structure with coefficients of arbitrary length.

The invention provides a four-dimensional ultrasonic signal real-time enhancement method based on anisotropic multiphase decomposition and LTI constraint, and belongs to the field of medical image processing. The method comprises the following steps: constructing a space-time Laplacian pyramid and anisotropic multiphase decomposition, constructing a space-time multiphase filtering network based on dimension decoupling, performing LTI constraint solution based on transposer error minimization, performing cross-scale multiphase feature alignment based on Kronecker product, performing multiphase synthesis inverse rearrangement, and performing image reconstruction. The behavior of the system is described by using the pulse response in the signal processing theory, the shift characteristic introduced by multiphase decomposition is eliminated, the LTI strong constraint is introduced in the filter coefficient optimization stage, and the constraint forces convolution kernel parameters in the space-time multiphase filter network to form a specific complementary structure, so that the performance of the system is improved. According to the invention, different multi-phase components can counteract aliasing terms during synthesis, so that checkerboard artifacts are eliminated macroscopically, low-frequency structure direction information is ensured to accurately cover each high-frequency sub-pixel phase, and no phase deviation exists.

The application discloses a digital down conversion design method of a ride-free architecture, belongs to the field of digital down conversion, and inputs a digital intermediate frequency signal, which is down-converted to a baseband by a mixing module, and then is subjected to a low-pass digital decimation filter module to complete a down-sampling function and filter out high-frequency components. In wideband / narrowband channel multiplexing high-speed sampling, in order to reduce the mixing operation complexity and take into account subsequent signal processing, the relationship between the local oscillator signal frequency and the sampling frequency of the radio frequency receiving system is coordinated, the carrier frequency of the intermediate frequency signal is set as f LO =f s / 8, and the frequency band of interest is down-converted to a low-frequency band; the integrator module in the CIC filter is subjected to polyphase decomposition, and 12 times decimation is realized after being converted into 4-way parallel data. The comb filter module adopts a half-byte serial algorithm and multiplexing technology, so as to reduce power consumption and area; the four-way parallel signals after filtering are subjected to linear combination, and the CSD coding algorithm is utilized, so as to finally linearly combine the 4-way data to separate real and imaginary signals.

This invention relates to the field of filter technology, and particularly to a design method, system, device, and medium for a quasi-completely reconstructed filter bank. The method first uses a generalized monotonic asymptotically saturated function as the initial value of a prototype filter, substituting it into the filter bank model for optimization to obtain a baseline fully reconstructed prototype filter. Then, a transition band adjustment parameter is introduced to perform an analytical mapping transformation on the amplitude-frequency response of the baseline fully reconstructed prototype filter, resulting in a fully reconstructed prototype filter with optimized transition band. Finally, combined with a determined number of filter bank channels and the polyphase decomposition length of the prototype filter, a quasi-completely reconstructed prototype filter is obtained through frequency domain sampling and transformation processing, which is then modulated to obtain a quasi-completely reconstructed filter bank. This method, by introducing a generalized monotonic asymptotically saturated function as the initial value of the prototype filter and combining it with the analytical mapping mechanism of the transition band adjustment parameter, significantly improves stopband attenuation performance and increases the efficiency of prototype filter coefficient generation while ensuring quasi-complete reconstruction.