Design Of High-precision Phase Difference Detecting System

Papers come from the project of hydrocephalus detection based on phase shiftspectroscopy of magnetic induction (PSSMI). The technology of digital circuit testingphase difference is applied to the phase shift spectrum. There is a wide range ofapplications and prospects.Excitation signal of different frequenciey is applied to brain tissue resulting phaseshift spectrum, and the phase shift spectrum is associated with the water content of thetissue. According to the above principle, the design of phase difference detection basedon DFT is given in the paper. Excitation and reference signal is passed through thefilter and is converted to digital signal by ADC. The DSP hardware detects phasedifference and the phase curve is drawn on the LCD. This paper analyzes the basicprinciple of phase difference detection, calculates and simulats the parameters of thecircuit, designs hardware circuits, writes software, and achieves high-precision phasedifference detection.This system successfully reaches all the desired functions and indicators. Aftertesting, it has been applied to the project of the Hydrocephalus detection.