基于低仰角对流层散射双向时间比对的多基地雷达时间同步研究

In large region of complex terrain and strong electromagnetic interference conditions, maneuvering & autonomous time synchronization in high precision for multistatic radar is a key technical problem. Two-way time transfer (TWTT) theory is applied to the troposcatter channel which possesses with over-the-horizon wireless transmission performance in our project. It establishes the troposcatter channel transmission delay error model in low elevation of C wave band and studies tropospheric propagation delay errors in troposhperic refraction, multipath fading, meteorologic environments and different transfer lengths , fast clock errors calibration and clock errors prediction in uncertain length, by adopting the improved ray-tracing, BBPLL technology and combined artificial intelligence optimization algorithms, thus achieving the multistatic radar time synchronization precision in ns level, so as to enhance the multistatic radar’s detection, localization, tracking and guidance performance. In addition, it will expand application fields of TWTT. The project and its expected research results will provide an independent time synchronization means for multistatic radar with abilities of far transmission distance, good obstacle performance, strong maneuverability. And it is of important theory significance and application value of promoting multistatic radar detecting & early warning ability and regional air anti-missile defence ability in our country.

在大区域复杂地形和强电磁干扰条件下，多基地雷达机动自主的高精度时间同步是一个关键技术难题，本项目将双向时间比对理论应用于具有超视距无线传输性能的对流层散射信道，建立C波段低仰角对流层散射信道传输延迟误差模型，采用改进的射线描迹法、BBPLL技术和组合人工智能优化算法，开展对流层大气折射、多径衰落、气象环境和比对距离等因素对比对精度的影响，快速钟差校准和预报时长不确定的钟差预报等方面内容研究，实现多基地雷达纳秒量级的时间同步精度，从而提升多基地雷达的探测、定位、跟踪和制导性能，并拓展双向时间比对的应用领域。本项目的开展及预期研究成果将为多基地雷达提供一种传输距离远、越障性能好和机动性强的自主时间同步手段，对提升我国多基地雷达探测预警和区域国土防空反导能力具有重要的理论意义和应用价值。

针对大区域复杂地形和强电磁干扰条件下多基地雷达时间同步需求，本项目在对流层散射双向时间比对传播延迟误差、不定时长钟差预报及快速钟差校准等方面展开了研究，建立了对流层散射单向/双向时间比对模型，分析了对流层散射信道性能，估计了低仰角下的对流层传播延迟误差，进行了预报时长不确定情况下的钟差预报，设计了一种低抖动宽捕获带的钟差校准算法，开发了对流层散射时间同步试验模块，开展了对流层散射时间同步试验，验证了对流层散射信道传输时间同步信号实现多基地雷达各站之间时间同步的可行性，产生发明专利6项，出版专著1部，发表学术论文24篇，对对流层散射时间同步方法应用具有较高的理论价值，支撑获得军队科技进步一等奖1项、培养博士后1名、博士研究生3名、硕士研究生2名。