Design of Lock-In Amplifier Based on Down-Sampling Mean Filter

Abstract

Low-pass filter is an integral part of lock-in amplifier, low-pass FIR or IIR filter is typically used in lock-in amplifier, which need a large number of multiplications and occupy more hardware resources. To reduce cross-correlation computing requirement of multiplications, this paper, designed orthogonal vector lock-in amplifier based on the down-sampling dual mean filter. Experiments show that, the digital amplifier has good detection performance and noise or clutter suppression. Keywords: lock-in amplifier, mean filter, down-sampling, Gaussian noise suppression, clutter suppression.