Non-contact Vocal Cord Vibration Sensing Technology Research

Contactless vocal vibration detection technology uses radar detect the micro vibration of human vocal organs, through processing and analyzing the echo signal data, we can obtain the related parameters of human vocal vibration, thus reducing sound information. Applications will extend to medical treatment, communication, and national defense military purposes.we design the radar system based on the contactless vocal vibration detection principle. System includes radar signal emission part, simulation receiving part, digital down-conversion part and digital signal processing part. Radar signal emission part use local oscillator produce conform to the index requirements of the continuous wave signal, through the transmitting antenna launch out; Simulation receiving part through the receiving antenna receiving echo, echo after low noise amplifier, radio frequency band-pass filtering, mixing, band pass filter, the radio frequency signals are converted to intermediate frequency signal; Digital down-conversion bandpass sampling the signal,make the signal frequency convert to baseband, through the extraction filtering processing realize the sampling rate conversion, high sampling rate signal convert to appropriate low speed signal; Digital signal processing part process the two baseband signal of I and Q through arctan and frequency extraction processing, finally we get the actual situation of human vocal vibration, so that we can reducing the sound information.This paper adopted FPGA+DSP system solutions, make the system more intelligent and miniaturization, among them, the digital down-conversion part by FPGA realization, digital signal processing part by DSP realization, and at the same time, the scheme make the contactless vocal vibration detection technology has a broad prospect of application.