The Application of Adaptive Filter with Single Sensor

• Main Authors: Yi-Wen Chen, 陳義文
• Other Authors: Yen-Lei Ling
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/88284934918586988427

碩士 === 義守大學 === 電子工程學系碩士班 === 95 === In order that compare the effect of the adaptive filter with the analogy filter. We create received pulse signal using computer simulation. We processe the 60Hz power line noise and AWGN within the received signal by using adaptive filter and analogy filter. We use a sensor and two independent adaptive filters in the system, the first adaptive filter process the 60HZ power line noise. The second adaptive filter process AWGN. Finally, we concentrate on the variation of pulse signal. When the power line signal fluctuates near 60HZ, we compare analogy filter and adaptive filter. Finally, we compare the performance of the proposed filter with the adaptive Notch filter. Conventional adaptive filter, as typified by the well-know LMS algorithm, use an instantaneous estimate of the error-surface gradient to update the filter coefficients. Such a strategy leaves the algorithm extremely vulnerable to impulsive signal. The median normalized least-mean square (MNLMS) algorithm is presented and demonstrate that the MNLMS can filter out impulsive interference. The MNLMS is best than the median least-mean square(MLMS) and the normalized median least mean square(NMLMS) for variation of input power, speed of convergence, variation of length of window, and Gaussian environments. Finally, we analyze effect of preprocessor of impulsive interference; we compare different power level of impulsive interference. By compter simulation, we illustrate that preprocessor based on output signal power level of adaptive filter is best.