Investigation on THz Interferometer System Based on High Speed Digital Correlator
HAN Donghao①② LIU Hao① WU Ji① WU Qiongzhi③ ZHANG Dehai① LU Hao① Zhang Ying①②
①(Key Laboratory of Microwave Remote Sensing, National Space Science Center, Chinese Academy of Sciences, Beijing 100190, China) ②(University of Chinese Academy of Sciences, Beijing 100049, China) ③(Beijing Institute of Technology, Beijing 100081, China)
As a conventional unit in interferometric imager, correlator has a wide range of applications to get visibility functions. THz imager has more and more applied to security check and military scouting area. To solve the phase synchronization problem in high speed digital correlator, which is designed for THz interferometer, this paper presents a cross synchronization scheme based on low hardware cost FPGA controller. A high speed multichannel digital correlator is presented under this scheme. In this correlator, sampling rate can reach as high as 5 GHz, effective number of ADC is greater than or equal to 6 bit, integration time is adjustable. Interference fringes are presented by constructing a 0.44 THz interferometer out of this correlator and related THz microwave devices. The fringe’s linear phase error is better than 2°. The research could provide important reference value about the design of THz interferometric imager in future.
韩东浩,刘浩,吴季,吴琼之, 张德海,陆浩,张颖. 基于高速数字相关器的太赫兹干涉仪系统研究[J]. 电子与信息学报, 2016, 38(4): 964-969.
HAN Donghao, LIU Hao, WU Ji, WU Qiongzhi, ZHANG Dehai. Investigation on THz Interferometer System Based on High Speed Digital Correlator. JEIT, 2016, 38(4): 964-969.
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