Unlock instant, AI-driven research and patent intelligence for your innovation.

Linear frequency modulation signal phase recovery method based on fractional order short-time Fourier transform

A linear frequency modulation signal, short-time Fourier technology, applied in the field of signal processing, can solve the problems of signal distortion, the effect is not very good, the signal error increases, etc., to achieve the effect of strong anti-interference ability and accurate recovery

Active Publication Date: 2019-11-05
XI'AN PETROLEUM UNIVERSITY
View PDF5 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] Although the traditional GS phase recovery method can recover the phase of the signal, it still has some shortcomings: first, as the signal to be processed changes from a stationary chirp signal to a non-stationary chirp signal, at this time, the traditional The effect obtained by decomposing this non-stationary linear FM signal is often not very good; secondly, the traditional GS phase recovery method will be affected by noise in the iterative process. After the noise is introduced, the noise will lead to The signal error output by the traditional GS phase recovery method increases, and even causes signal distortion

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Linear frequency modulation signal phase recovery method based on fractional order short-time Fourier transform
  • Linear frequency modulation signal phase recovery method based on fractional order short-time Fourier transform
  • Linear frequency modulation signal phase recovery method based on fractional order short-time Fourier transform

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0050] see figure 1 with figure 2 , a linear frequency modulation signal phase recovery method based on fractional short-time Fourier transform, comprising the following steps:

[0051] step one:

[0052] 1.1 Input the following functions: amplitude information y(m,u); signal x to be processed with random phase and random noise introduced i＝0 (t);

[0053] 1.2 Select the rectangular window function

[0054] 1.3 Enter the following parameters: rotation angle The support domain of the window function W=12, the signal length N=29, the moving step of the adjacent window function L=2, the moving times of the window function m=15, the number of cycles i, at this time i=0, the signal-to-noise ratio SNR= 30;

[0055] Step 2, let i=i+1, through formula 2-1

[0056]

[0057] to x i-1 (t) Perform fractional short-time Fourier transform to get

[0058] Step 3, through formula 3-1

[0059]

[0060] right Perform processing, retain phase information, and update amplitu...

Embodiment 2

[0073] see figure 1 with figure 2 , a linear frequency modulation signal phase recovery method based on fractional short-time Fourier transform, comprising the following steps:

[0074] step one:

[0075] 1.1 Input the following functions: amplitude information y(m,u); signal x to be processed with random phase and random noise introduced i＝0 (t);

[0076] 1.2 Select the Gaussian window function;

[0077] 1.3 Enter the following parameters: rotation angle The support domain of the window function W=12, the signal length N=29, the moving step of the adjacent window function L=2, the moving times of the window function m=15, the number of cycles i, at this time i=0, the signal-to-noise ratio SNR= 30;

[0078] Step 2, let i=i+1, through formula 2-1

[0079]

[0080] to x i-1 (t) Perform fractional short-time Fourier transform to get

[0081] Step 3, through formula 3-1

[0082]

[0083] right Perform processing, retain phase information, and update amplitude...

Embodiment 3

[0095] see figure 1 with figure 2 , a linear frequency modulation signal phase recovery method based on fractional short-time Fourier transform, comprising the following steps:

[0096] step one:

[0097] 1.1 Input the following functions: amplitude information y(m,u); signal x to be processed with random phase and random noise introduced i＝0 (t);

[0098] 1.2 Select the Gaussian window function;

[0099] 1.3 Enter the following parameters: rotation angle The support region of the window function W=12, the signal length N=29, the moving step of the adjacent window function L=2, the moving times of the window function m=15, the number of cycles i, at this time i=0, the signal-to-noise ratio SNR= 30;

[0100] Step 2, let i=i+1, through formula 2-1

[0101]

[0102] to x i-1 (t) Perform fractional short-time Fourier transform to get

[0103] Step 3, through formula 3-1

[0104]

[0105] right Perform processing, retain phase information, and update amplitude...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention discloses a linear frequency modulation signal phase recovery method based on fractional order short-time Fourier transform. The method comprises the steps: firstly converting an original signal x (t) into a function y (m, u) with phase information removed and only containing amplitude information and a to-be-processed signal xi (t) with a random phase and random noise, and inputtingxi (t) into a program; enabling i to be equal to i+1, performing fractional order short-time Fourier transform on xi-1 (t) to obtain a phase of a reretention function, updating amplitude informationof the phase to obtain inverse transform, performing windowing function processing on the inverse transform, and updating iterative information to obtain xi (t); inputting the xi (t) into a program, circulating for a plurality of times, and finally enabling xr (t) to be equal to xi (t), so as to obtain a phase recovery signal xr (t). According to the method, interference of random noise can be eliminated. The accurate phase recovery can be carried out on signals with random phases. The method has the characteristics of strong anti-interference capability and accurate recovery. By using the method, a proper window function and a proper rotation angle can be selected according to the characteristics of the signal.

Description

technical field [0001] The invention relates to the technical field of signal processing, in particular to a linear frequency modulation signal phase recovery method based on fractional-order short-time Fourier transform. Background technique [0002] There is a classic method in the field of phase recovery—GS phase recovery method, which is to decompose the smooth chirp signal into the superposition of several sinusoidal signals through the traditional short-time Fourier transform of the intensity information of the signal on the input surface and the output surface , and then update the amplitude information, and then perform inverse transformation on the signal with updated amplitude information, and iteratively reduce the error of the inversely transformed signal several times, and finally restore the signal with missing phase information to a signal with phase information. [0003] Although the traditional GS phase recovery method can recover the phase of the signal, it...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): G06F17/14
CPCG06F17/141Y02D30/70
Inventor 李岚毛朝阳林玮张瑞琼
Owner XI'AN PETROLEUM UNIVERSITY