Abstract：In order to eliminate the limitations of Doppler signal software demodulation in high-frequency acoustic applications,a digital hardware signal demodulation approach based on FPGA is proposed.It contains a high-speed ADC acquisition system based on AD9467 to implement the Nyquist sampling or band-pass sampling of the original Doppler signal.The digital signal processing system based on Xilinx Zynq-7000 SoC is designed to generate the I&Q baseband signal pair,which is obtained by mixing of DDS synthesized reference signal with Doppler signal and the following low-pass filtering.The CORDIC algorithm and phase unwrapping algorithm are used to demodulate the I&Q baseband signal pair and the real-time demodulation of Doppler signals is initially realized.Numerical simulation in the frequency range from 50kHz to 500kHz and the preliminary experimental results in the frequency range from 50kHz to 300kHz demonstrate the validation of the demodulation method and system.
柯伟,冯秀娟,杨平,何龙标,邢广振,王敏. 基于FPGA的激光外差干涉仪反正切解调技术[J]. 计量学报, 2022, 43(3): 399-404.
KE Wei,FENG Xiu-juan,YANG Ping,HE Long-biao,XING Guang-zhen,WANG Min. Technology of Arctangent Demodulation of Laser Heterodyne Interferometer Based on FPGA. Acta Metrologica Sinica, 2022, 43(3): 399-404.
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