微波光子四倍频复合雷达信号生成及目标多维度探测

In radar systems, to achieve high-precision multi-dimensional measurement of targets, radar signal generation is a basic and important function. A microwave photonic frequency-quadrupled composite radar signal generation approach is proposed. The composite radar signal includes a single-chirped linearly frequency-modulated (LFM) signal and a single-tone microwave signal. The single-tone microwave signal and the single-chirped LFM signal are jointly used to measure the radial velocity of a target, while the single-chirped LFM signal is used to measure the distance of the target and implement the high-resolution microwave imaging. In the transmitter, an up-chirped LFM signal with an instantaneous bandwidth of 2 GHz and a 13.2 GHz single-tone microwave signal are generated using a photonic frequency quadrupler. In the receiver, target echo signals are de-chirped and then used to achieve the measurement of distance and radial velocity and the high-resolution ISAR imaging. Experimental results show that the absolute measurement errors of distance and radial velocity are no more than 4.2 cm and 1.7 cm/s, respectively, and the imaging results of multiple targets are clear and identifiable.