机身共形圆台阵结构对地杂波谱特性影响分析

针对共形阵情形下,采样协方差矩阵求逆(sampling matrix inversion, SMI)得到的最小方差谱会发生很大程度的展宽,进而影响目标检测性能的问题,提出了增益谱分析方法。该方法利用增益权进行杂波处理,即在权中考虑了阵元增益,因此能够更好地对实际杂波进行匹配。在所提方法的基础上,重点分析了机身共形圆台阵圆心角和阵元主瓣宽度对杂波特征值、最小方差谱及增益谱的影响,为实际共形阵杂波抑制时共形阵结构的选择提供了重要的指导意义。仿真结果表明,较大的主瓣宽度可以使最小方差谱展宽减小,而较大的圆心角可以使增益谱的性能更优,并且,利用增益权处理可以有效提高主瓣杂波下目标的检测性能,且当圆心角较大时,增益权的处理结果明显优于传统SMI。

Analysis of the effect of the fuselage conformal frustum array structure on the property of the ground clutter spectrum

In the condition of conformal array, the minimum variance spectrum with sampling matrix inversion (SMI) extends much, which has an influence on the target detection. So the method of using the gain spectrum to analyze is proposed. In the method, the gain weight is used to process the clutter, that is, the element gain is contained in the gain weight to match the actual clutter better. The effects of the central angle and element main lobe width on eigenvalue, the minimum variance spectrum and the gain spectrum of the clutter are mainly analyzed on the basis of this method. Important suggestions are provided for the structure selection of the conformal array for clutter suppression. The simulation results indicate that a larger main lobe width makes the minimum variance spectrum extend smaller and a bigger central angle makes the gain spectrum get better performance. Besides, for the case of clutter in main lobe, the gain weight can be used to effectively improve the performance of the target detection. When the central angle is large, the gain weight can evidently get a better processing result than the traditional SMI.