Passive bistatic radars have been reported to detect and track drones, general aviation aircraft, and civil aviation aircraft extensively. However, localization performance is limited by the poor azimuth estimation. On the other hand, lots of digital television broadcasting transmitters have sprung up, and they work at different frequencies. In order to utilize the spatial diversity of the transmitters with one receiver, the time-division-multifrequency(TDMF)-based passive radar is constructed. The TDMF system reports the target observations from different transmitters sequentially like an asynchronous system. We proposed a target tracking method to make full use of the spatial diversity. The method is divided into two stages, namely extrapolated bistatic tracking and Cartesian tracking. Extrapolated bistatic tracking is designed to solve the asynchronous problem and guarantees a high-accuracy initial track. Then, the measurements from different transmitters are utilized to update the Cartesian tracks sequentially. This spatial diversity leads to a high-accuracy track. The posterior Cramer-Rao bound for the TDMF system is also derived. Simulation and experimental results show close performance to the simultaneous multifrequency passive radar. Furthermore, field experimental data verifies the feasibility of the proposed approach.

中文翻译：

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时分多频无源雷达中的目标跟踪

据报道，无源双基地雷达广泛用于检测和跟踪无人机、通用航空飞机和民航飞机。然而，定位性能受到较差的方位角估计的限制。另一方面，大量数字电视广播发射机如雨后春笋般涌现，它们以不同的频率工作。为了利用发射机和接收机的空间分集，构建了基于时分多频（TDMF）的无源雷达。TDMF 系统像异步系统一样按顺序报告来自不同发射机的目标观测值。我们提出了一种充分利用空间多样性的目标跟踪方法。该方法分为两个阶段，即外推双基地跟踪和笛卡尔跟踪。外推双基地跟踪旨在解决异步问题并保证高精度的初始跟踪。然后，利用来自不同发射器的测量结果来依次更新笛卡尔轨迹。这种空间多样性导致高精度轨迹。TDMF 系统的后 Cramer-Rao 界也被推导出来。仿真和实验结果表明性能接近同步多频无源雷达。此外，现场实验数据验证了所提出方法的可行性。仿真和实验结果表明性能接近同步多频无源雷达。此外，现场实验数据验证了所提出方法的可行性。仿真和实验结果表明性能接近同步多频无源雷达。此外，现场实验数据验证了所提出方法的可行性。