一种天波超视距雷达分级Hough变换航迹起始方法

天波超视距雷达固有的低数据率、低检测概率和低量测精度等特征对航迹起始方法提出新的挑战。本文提出了一种天波超视距雷达两级Hough变换航迹起始算法(TH-HT)。该方法首先采用时间-径向距离数据进行第1级Hough变换，将多普勒量测作为积累约束条件来避免无效积累，得到候选航迹；之后对与每条候选航迹相应的时间-方位角数据进行第2级Hough变换，最终得到确认航迹。通过描述各级积累单元获得杂波投票数期望的定理，给出两级阈值的确定方法。与MMUPDA的仿真比较表明，TH-HT不但具有较高的航迹起始概率和较低的虚假航迹概率，而且运行时间大大降低。

A Two-hierarchy Hough Transform Based Track Initiation Method for Sky-wave Over-the-Horizon Radar

The 3L (low data sampling rate, low measurement precision and low detection probability) features of sky-wave Over-The-Horizon Radar (OTHR) pose new challenges to the conventional track initiation methods. In this paper, a Two-Hierarchy Hough Transform track initiation method (TH-HT) is proposed. Firstly the range-time data space is used to hierarchical I Hough transform and rough candidate tracks are obtained, where Doppler is used as an accumulation constraint; then such rough candidate tracks are further refined by time-azimuth accumulation in hierarchical II Hough transform. Moreover, two theorems concerning the expectation of the number of clutters voting to each cell of each hierarchy are given, which provides a way of determining the two-hierarchy threshold value. In simulation, the proposed method is compared with the classical initiation method of OTHR-MMUPDA. Simulation results show that TH-HT has higher track detection probability and lower false track probability; meanwhile it is much less time-consuming.