机载多载频频控阵非均匀距离模糊杂波抑制方法

Non-uniform distance ambiguity clutter suppression method for airborne multi-carrier frequency control array

机载雷达下视工作面临严重的地海杂波,雷达平台运动造成杂波多普勒频率严重扩散,将微弱目标完全淹没。空时自适应处理(space time adaptive processing,STAP)技术通过联合多天线脉冲的接收信号,能够有效地抑制杂波,实现运动目标检测。对于非正侧视阵列高速平台雷达,杂波距离依赖和距离模糊严重制约着目标检测性能。基于多载频频控阵,通过发射一组载频不同的正交信号,在杂波回波中,获得新的发射维自由度,并根据不同模糊在发射维的差异分离各模糊区域。此外,通过进一步对分离后的近程进行杂波补偿,利用降维STAP实现杂波抑制。仿真结果验证了所提方法的有效性。

The looking-down mode of the airborne radar faces serious low-sea clutter,and the Doppler frequency of clutter spreads seriously due to the movement of radar platform,which will completely submerge the weak target.Space-time adaptive processing(STAP)technology can effectively suppress clutter and realize moving target detection by combining the received signals of multi-antenna pulses.For non-side-looking array high-speed platform radar,clutter range dependence and range ambiguity seriously restrict the performance of target detection.In this paper,based on the multi-carrier frequency control array,by transmitting a group of orthogonal signals with different carrier frequencies,a new degree of freedom of the transmit dimension is obtained in the clutter echo,and the range-ambiguous regions are separated according to the difference of distinct ambiguities in the transmit dimension.In addition,by further compensating the short-range clutter after separation,a reduced-dimensional STAP is used to mitigate the clutter.Simulation results verify the effectiveness of the proposed method.