1results about "Pulse demodulator" patented technology

The application belongs to the technical field of test and measurement of optical fiber sensing and signal processing, and discloses a distributed acoustic sensing system based on pulse compression and a signal demodulation method. In the method, original echo signals are collected and segmented according to a pulse repetition period to form sample traces; a multi-band sub-match filter bank is constructed, fast Fourier transform, frequency domain complex multiplication and inverse fast Fourier transform are respectively performed on the sample traces in each frequency band, and a pulse compression complex sequence is obtained; group time delay compensation is performed on the reference band, so that each frequency band is aligned under the reference of uniform sample point sequence numbers; a phase reference is established by taking the complex conjugate of the pulse compression complex sequence of the first sample trace point by point, and phase correction is completed by performing point-by-point complex multiplication on the subsequent sample traces; complex vector superposition is performed on the phase correction results of each frequency band, a demodulation output is obtained, and the phase reference is updated according to a phase refresh period.