相位编码正交频分复用雷达信号设计与旁瓣抑制

Phase-coded Orthogonal frequency-division multiplexing (OFDM) radar is one of the new radars proposed in recent years, which has several advantages, such as flexible waveform, digital processing, achieving high resolution in both range and Doppler domain, and so on. The potential application includes anti-jamming, multifunction, and intelligence. However, there are two foundational problems, one is signal design, including high peak to mean envelope power ratio (PMEPR) and phase-coded design of waveforms, the other is the sidelobe suppression of pulse compression. Aiming to solve these two problems, the project is going to address the signal design and sidelobe suppression for phase-coded OFDM radar. The design scheme of a chaotic phase-coded OFDM radar signal is proposed, to lower PMEPR, enhance flexibility, and improve autocorrelation simultaneously. A sidelobe cancellation method based on pulse pairs with complementary codes and a new phase compensation method are proposed to suppress sidelobes of pulse compression effectively. The potential of performance, such as low probability of intercept (LPI), anti-jamming, detection of weak targets and so on, will be validated sufficiently by this project. And it will support the development of new radar systems.

相位编码正交频分复用是雷达领域近年提出的新体制信号形式，具有波形设计灵活、易于数字化、距离多普勒高分辨等优点，在抗干扰、多功能、智能化等方面有很大潜力。该信号体制存在两个基础性问题有待解决，一是发射信号设计，包括波形峰均比的降低和编码的设计，二是回波的脉冲压缩旁瓣抑制。针对这两个问题，本项目重点开展相位编码正交频分复用雷达信号设计与旁瓣抑制研究，其中，提出混沌相位编码OFDM雷达信号设计方案，兼顾降低发射波形的峰均比、增强信号的灵活性和改善编码的自相关性质；提出基于互补编码脉冲对的旁瓣对消方法和相位补偿新方法，有效降低脉冲压缩旁瓣。项目力图充分挖掘该新体制雷达信号在低截获、抗干扰、弱小目标检测等方面的潜力，为新体制雷达设计与研制提供核心技术支撑。

相位编码正交频分复用是雷达领域近年提出的新体制信号形式，具有波形设计灵活、易于数字化、距离多普勒高分辨等优点，在抗干扰、多功能、智能化等方面有很大潜力。该信号体制存在两个基础性问题有待解决，一是发射信号设计，包括波形峰均比的降低和编码的设计，二是回波的脉冲压缩旁瓣抑制。针对这两个问题，本项目重点开展了相位编码正交频分复用雷达信号设计与旁瓣抑制研究。在发射信号设计方面，提出混沌相位编码OFDM雷达信号优化设计方案，从现有混沌序列特性出发，提出了一种混沌量化映射法则，由混沌序列获得了正交性能良好的多相编码集。基于相位编码OFDM信号包络峰均比和自相关函数峰值旁瓣比，基于迭代限幅方法获得了同时满足雷达发射机要求 且相关性能优良的相位编码OFDM信号，形成了一套系统的相位编码OFDM信号波形设计和优化方案。在回波信号处理方面，提出基于互补编码脉冲对的旁瓣对消方法和基于循环前缀的多普勒频偏估计与补偿算法，有效降低脉冲压缩旁瓣，改善了多普勒失配情况下的峰值幅度损失。项目充分挖掘该新体制雷达信号在低截获、抗干扰、弱小目标检测等方面的潜力，为新体制雷达设计与研制提供核心技术支撑。