介绍了一种具有双接收通道的太赫兹成像雷达,雷达工作频率为216 GHz,系统设计中,采用直接数字式频率合成器以及频率综合等方式,产生具有800 MHz 带宽的Ku 波段线性调频连续波信号,功分后分别与两个点频信号进行混频,产生36 GHz依400 MHz 的射频信号以及35. 95 GHz依400 MHz 的本振信号,分别驱动太赫兹发射机和接收机。本振信号功分两路,送入两个接收机,接收采用去斜接收体制,从而降低数据率。该雷达采用了6 倍频太赫兹发射模块,最终产生系统带宽为4. 8 GHz,从而获得3 cm 的距离分辨率。文中还重点研究了宽带系统标校,并开展了高分辨逆合成孔径成像实验,为后续太赫兹干涉合成孔径成像雷达研究奠定基础。

This paper introduces one terahertz imaging radar with double receiving channels. The working frequency of the radar is 216 GHz. In the system design, a Ku-band chirp signal with 800 MHz bandwidth is generated by using Direct Digital Synthesizer (DDS) and frequency synthesizer. Then the Ku-band signal is divided into two signals, which are mixed with two point frequency to produce a 36 GHz 400 MHz RF signal and a 35. 95 GHz 依400 MHz LO signal, respectively, driving the THz transmitter and receiver. The LO signal is divided into two signals and sent to two receivers. The receiver uses dechirp method to reduce the data rate. The radar uses a terahertz transmission module with 6 frequency multiplier, resulting in a system bandwidth of 4. 8 GHz, so the distance resolution of this radar is 3 cm. This paper also focuses on the calibration of broadband systems, and carries out high resolution inverse synthetic aperture imaging experiments, which lays the foundation for the research of terahertz interferometric synthetic aperture radar.

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