Method for suppressing interference of echo-impact response of frequency modulated continuous wave(FMCW) radar fluid-level meter

Abstract

The invention provides a method for suppressing interference of echo-impact response of a frequency modulated continuous wave(FMCW) radar fluid-level meter. The method is characterized by including the following steps of detecting impact response interference zone, analyzing measured detecting sampling points in a way of x<0>,x<1>,...x<N-1>; detecting detecting sampling points which are satisfied with the formula (1)(the formula is as shown in the description) in time-domain, wherein the x,(i=0, 1, 2...N-1) represents the ith sampling point; taking fifteen points of the left side and the right side of an amplitude maximum point in the detecting sampling points respectively as the impact response interference zone, and if points on the left side of the detecting sampling points are less than fifteen points, taking all sampling points from the first point on the left side to the amplitude maximum point; drugging out detecting sampling points in the impact response interference zone in the original signal of time-domain and compensating zero; predicting and interpolating based on auto regressive(AR) model.

Description

technical field [0001] Radar level gauge ranging technology Background technique [0002] In foreign countries, FMCW radar level gauge is widely used in petrochemical and storage industries, and is the core sensor of oil storage tanks. FMCW uses continuous signal transmission and processing instead of pulse radar signal transmission-wait-receive intermittent work method, it is more suitable for process tanks, mixing tanks and other occasions where the liquid level is severe, and it is used in high-end applications (Rosemount Radar Level Co., Ltd. Radar Level Measurement. Invention Patent, Patent Application No.: CN200710153641.0) . [0003] However, during the development of the radar level gauge, due to the transient impulse response of the receiving channel of the radar receiver, the impulse response interference is caused to the radar echo. This interference is mainly impact noise, which is much stronger than that of the oil tank. Liquid level echo, this kind of interfe...

AI Technical Summary

Problems solved by technology

[0003] However, during the research and development of radar level gauges, due to the transient impulse response of the receiving channel of the radar receiver, the impulse response interference is caused to the radar echo. This interference is mainly impact noise, which is much stronger than that of the oil tank. Liquid level echo, this kind of interference makes the SNR of the target drop sharply, which leads to misjudgment of the target detection, and then affects the measurement accuracy of the radar level gauge. At the cm level, it does not meet the order of magnitude of the mm level.

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