3 results about "Z-transform" patented technology

The application discloses a kind of pulse shaping method and system of nuclear signal, belong to signal processing technical field, for the problems of existing pulse signal width in prior art Widening, thereby increasing the accumulation event, and there is no better anti-noise effect to Gaussian white noise, the present application includes: the output signal of detector is acquired, and output signal is structured into digital function signal;The Z transform is carried out after the discrete of the digital function signal, and output Z transform signal is obtained;Definition input signal is exponential signal, and the Z transform is carried out to the exponential signal, and input Z transform signal is obtained;According to the input Z transform signal and the output Z transform signal, the transfer function of input signal pulse shaping is obtained;The inverse Z transform is carried out to the transfer function, and the pulse shaping signal of input signal is obtained, and its time domain expression.The purpose is: the pulse shaping signal obtained has better signal-to-noise ratio, and it is convenient to obtain amplitude.

This application discloses a SAR imaging method for sea surface ship targets based on inverted conjugate-frequency modulated Z-transform and maximum likelihood estimation, belonging to the field of radar target imaging technology. The method includes: establishing a geometric motion model of the ship target based on its motion; calculating a range-time domain echo signal model based on the geometric motion model; adaptively extracting the echo signal from the echo signal model based on the inverted conjugate-frequency modulated Z-transform; establishing a linear observation equation for phase error using the echo signal to optimally estimate the two-dimensional spatially varied phase error parameters; constructing a compensation function using the optimally estimated two-dimensional spatially varied phase error parameters and performing adaptive iteration based on bandwidth contraction to transform the iterated target signal from the time domain to the image domain, obtaining the final imaging result. This application can effectively eliminate complex two-dimensional spatially varied defocus, improving image resolution and focusing quality.

The invention discloses a flicker parameter estimation method and module based on windowing optimization linear frequency modulation Z transformation, and relates to the field of electric energy quality monitoring. The method comprises the steps that a voltage flicker signal in a power distribution network is acquired; performing envelope extraction on the voltage flicker signal by adopting an improved square detection algorithm to obtain a flicker envelope signal; a Kaiser-Nuttall mixed window function is applied to the flicker envelope signal, linear frequency modulation Z transformation analysis is carried out, and a discrete frequency spectrum is generated; and based on the discrete spectrum, correcting the frequency and amplitude of the flicker parameter by adopting a triplet spectrum interpolation algorithm to obtain a high-precision flicker parameter estimation result. According to the method, accurate extraction of a flicker envelope is realized by improving square detection and analytic modal decomposition, spectrum leakage is inhibited by combining a Kaiser-Nuttall mixed window with linear frequency modulation Z transformation, and finally, high-precision estimation of a module on a flicker amplitude value and a frequency parameter in an electric energy quality monitoring device is realized by combining a triplet spectrum interpolation algorithm.