A weak signal detection system: Design and simulation

In many cases, the signal of interest is obscured by noise. Noise such as the inherent noise of system and the interference of the external environment is inevitable, so a weak signal detection system is designed in this paper to solve the de-noising problem in strong noise backgrounds. The core of the system is a dual-phase lock-in amplifier based on an analog multiplier. Lock-in Amplifier (LIA) has the advantages like stable center frequency, narrow band-pass, high quality factor and so on. Simulation way (using MATLAB/SIMULINK) is adopted in this paper to show the effect of the weak signal detection system based on LIA, and then the TINA software is used to help hardware design. Simulation experiments results show that the method proposed in this paper works well.