天波超视距雷达瞬态干扰抑制方法

瞬态干扰是影响天波超视距雷达检测性能的主要因素之一,因此必须对瞬态干扰进行抑制.提出了一种改进复经验模式分解方法以抑制天波超视距雷达中的瞬态干扰.该方法利用小波包分解将回波信号先分解成一系列窄带信号,再对每一个窄带信号进行复经验模式分解,然后对各个固有模态函数进行归一化相关性筛选处理,最后对剩余信号进行瞬态干扰检测和剔除.该方法的主要优点是无须杂波抑制和数据预测重构.实测数据处理结果表明该方法能有效地检测和抑制瞬态干扰.

Method for transient interference suppression in the over-the-horizon radar

Transient interference is a primary factor impairing the detection performance of Over-the-Horizon Radar (OTHR), so it must be suppressed. Therefore, a novel method based on the improved Complex Empirical Mode Decomposition (CEMD) is proposed to suppress transient interferences in OTHR. The algorithm uses the wavelet packet transform (WPT) to decompose the signal echo into a set of narrow band signals prior to the application of CEMD. Then, each of the narrow band signals is decomposed into a set of IMFs by CEMD and a screening process is conducted to remove unrelated IMFs from the result. Finally transient interferences are detected and excised in the residual signal. A key advantage of the proposed method is that it requires neither to perform clutter suppression, nor to reconstruct data by using the prediction algorithm. This technique is applied to data from the OTHR, and the results show that the algorithm can efficiently detect and suppress transient interferences.