A method for improving the measurement data resolution of time-resolved spectroscopy (TRS) using adaptive pulse compression filter

Temporal and image resolution are the key problems in retrieving optical properties and in imaging of structural or functional changes within tissue from a set of received signals using a time-resolved spectroscopy (TRS) system. An adaptive light pulse compression filter applied to the signal processing of a TRS system is introduced, which was based on the analysis of temporal characteristics of near infrared spectroscopy (NIRS) signal. Moreover, an improved LMS algorithm having fast tracking ability and permitting large dynamic range input is also presented in this paper. The results of computer simulation, show that the filter has good tracing compression performance for diffusely reflected or transmitted signal received from the surface of the tissue and the temporal or image resolution of TRS system can be improved significantly.