Software Digital Lock-in Amplifier in the Application of fNIRS System
Xu Xian Yin, Baolei Xu, Zhi Dong Wang, Hong‐Yi Li, Shi Gang · Applied Mechanics and Materials · 2013
Lock-in amplifier is particularly important in the fNIRS-based system, because the lock-in amplifier can recover the low-level signals buried in significant amounts of noise. But the price of lock-in amplifier is very expensive. This paper presented a software method for designing digital lock-in amplifier. Compared with analogue lock-in amplifier, results show that software lock-in amplifier is feasible for experimental research and can replace the expensive analogue lock-in amplifier.