Method and circuit for pulse flow formation in sparse sampling of ultrasonic signals

Abstract

Disclosed are a method and a circuit for forming a pulse stream during sparse sampling of an ultrasonic signal. The method comprises: generating, by a local oscillator, an oscillating signal having a frequency double a center frequency of an ultrasonic signal S(t); dividing the oscillating signal by two and performing modulation and mixing on the respective signals and the S(t); passing two modulated and mixed signals through a low-pass filter to generate two output signals; and squaring the two output signals respectively, adding the squares, and calculating a square root of the sum, so as to obtain a final output signal A(t), wherein A(t) is a pulse stream obtained by detecting the ultrasonic signal S(t). The circuit comprises: a local oscillating module (S1), an orthogonal mixing module (S2), a low-pass filtering module (S3), and a modulo operation module (S4). The method and the circuit of the present invention are applicable to a sparse sampling system for an ultrasonic signal based on finite rate of innovation, so as to achieve sparse sampling at a rate much lower than the conventional Nyquist sampling rate, and thus resolving the issue in conventional sampling methods of overly large amounts of data, while retaining original signals and information, thereby enabling real-time formation of an ultrasonic pulse stream.

Description

technical field [0001] The invention belongs to the technical field of sparse sampling of ultrasonic signals, and in particular relates to a method for forming a pulse flow in sparse sampling of ultrasonic signals based on a limited innovation rate and a hardware front-end physical realization circuit. Background technique [0002] Ultrasonic testing is an important non-destructive testing method. In order to improve the detection efficiency, improve the detection rate and imaging resolution of internal defects of materials, multi-sensor array structure, high detection frequency, and long-term detection are often used. Obtain rich ultrasonic echo information of the target body. However, the unfavorable consequence is that there is a large amount of detection data, which brings great difficulties to the collection, transmission, storage and real-time processing of signals. In order to solve this problem, researchers have explored new data sampling methods other than the conv...

AI Technical Summary

Problems solved by technology

[0006] In order to solve the problem that the existing software algorithm cannot realize the direct physical sampling of ultrasonic signal FRI, the present invention proposes a physical formation method and circuit of ultrasonic pulse flow based on the principle of orthogonal demodulation, and uses analog circuits to realize the direct extraction of pulse flow from ultrasonic signals Signal

Images