Normalized LMS Filtering of Self-Mixing Interference Signal with Varying Frequency

Abstract

In actual measurement, the vibration frequency of the measuring object may change. In order to improve the accuracy of parameter estimation and measurement, this paper introduced the composition and filter principle of self-mixing interference system, and used the normalized LMS algorithm to simulate the interference experiment signal with frequency variation. The simulation results show that when the frequency of the signal changes, the weight coefficient of the filter is always in a small order of magnitude (10-3) dynamic change, which can quickly converge to a suitable value. The filtering effect is no different from the actual single frequency.