Opt Lett. 2023 Feb 1;48(3):767-770. doi: 10.1364/OL.481106.
A photonics-assisted radar receiver based on compressed sensing (CS) technology is proposed to receive frequency domain non-sparse radar signals. The radar echo signal is mixed with a pseudo-random binary sequence (PRBS) in a photonic random demodulator (RD) consisting of a laser diode (LD), a dual-drive Mach-Zehnder modulator (DD-MZM), and a photodetector (PD). After the mixed signal from the photonic RD is undersampled by an analog-to-digital converter (ADC), the echo signal is reconstructed in the digital domain using an overcomplete dictionary generated by the dictionary learning algorithm and sparse reconstruction algorithm. The target range can be then obtained by correlating the reconstructed echo signal and the transmitted one. Experimental results show that the proposed system can successfully reconstruct different kinds of undersampled non-sparse radar echo signals. When the compression ratio is 20, the ranging errors do not exceed 5 cm. The system provides a promising solution for recovering undersampled frequency domain non-sparse radar signals through photonics-assisted CS.
提出了一种基于压缩感知（CS）技术的光辅助雷达接收机，用于接收频域非稀疏雷达信号。雷达回波信号与光随机解调器（RD）中的伪随机二进制序列（PRBS）混合，光随机解调器由激光二极管（LD）、双驱动马赫-曾德尔调制器（DD-MZM）和光电探测器（PD）组成。在光RD 的混合信号被模数转换器（ADC）欠采样后，使用字典学习算法和稀疏重建算法生成的过完备字典在数字域重建回波信号。然后通过相关接收到的重建回波信号和发射信号可以得到目标距离。实验结果表明，该系统可以成功重建不同类型的欠采样非稀疏雷达回波信号。当压缩比为 20 时，测距误差不超过 5cm。该系统为通过光辅助 CS 恢复欠采样频域非稀疏雷达信号提供了一种有前景的解决方案。
