As a new technique of signal processing, wavelet analysis has excellent characteristics of time frequency localization and is suitable for analyzing time varying or transient signals.

This technique performs harmonic analysis of the nonspeech audio signals and then the resulted attributes including time-varying amplitude and frequency functions are piecewisely linearized.

The orthogonal sampling demodulating technique for low frequency time-code signal is introduced. Based on the theoretical analysis about its principle and implement method, The simulation is tested.