Filtering method and device for signal baseline drifting

Abstract

The invention discloses a filtering method and device for signal baseline drifting. The filtering method comprises the following steps: calculating the number of signals in each signal sampling value which is sampled at present, and placing the signal number in a first array built in advance; according to record information in the first array, calculating the signal number MidNum of a median, the number sum LessNum of signals less than the median and the number sum GreatNum of signals more than the median in the signal sampling value which is sampled at present; after the next signal sampling value is input, updating the numerical values of MidNum, LessNum and GreatNum; according to the relationship of the updated numerical values of MidNum, LessNum and GreatNum, updating the median of the signal processing value which is processed at present; and subtracting the updated median of the signal processing value which is processed at present from the current signal sampling value. According to the filtering method disclosed by the invention, the operation speed of the system is greatly improved.

Description

technical field [0001] The invention relates to the technical field of signal processing, in particular to a filtering method and device for signal baseline drift. Background technique [0002] In the communication field, there is usually a signal baseline drift phenomenon, and the baseline drift phenomenon will seriously affect the subsequent processing of the signal. [0003] For example, during the process of collecting, amplifying, detecting, and recording TV signals, they are often subject to various interferences from the outside world (such as rapid changes in ambient temperature, etc.), resulting in baseline drift of the TV signals. In a long period of time, the TV signal after baseline drift will mask noise and produce small fluctuations, and even make the TV signal exceed its specified value range, thereby seriously affecting the subsequent processing of the TV signal. [0004] Aiming at the phenomenon of signal baseline drift, the prior art usually uses the media...

AI Technical Summary

Problems solved by technology

In a long period of time, the TV signal after baseline drift will mask noise and produce small fluctuations, and even make the TV signal exceed its specified value range, thus seriously affecting the subsequent processing of the TV signal

[0004] Aiming at the phenomenon of signal baseline drift, the prior art usually uses the median filter method to filter the signal baseline drift. However, when the signal baseline drift is filtered directly using the median filter method, the In the case (such as filter window N=4096 signal sample values), since it is necessary to find the median of all signal sample values ​​in the filter window, it is necessary to sort the 4096 signal sample values ​​in each filter window , the running speed of its sorting algorithm is relatively slow, even if a faster sorting algorithm is used, it is often difficult to meet the requirements of the system running speed

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