宽带数字阵列雷达波束形成的优化实现方法

Optimized Beamforming Method of Wideband Digital Array Radar Based on Time Delay

针对射频采样宽带数字阵列雷达的特点,提出了一种基于可变分数时延滤波器,优化的实时数字时延波束形成方法。该方法根据射频采样后信号变换过程的特点,将抽取抗混叠滤波器与可变分数时延滤波器合并实现,减少了处理环节,并采用多相结构和Farrow结构相结合,实时地实现抽取和可变分数时延,从而得到不随频率偏移的波束指向。计算机仿真结果表明,该方法与整数倍时延波束形成方法相比,能够有效减小指向误差。

An approach of wideband beamforming to achieve accurate beam direction was pursued by the designers of the wideband digital array radar.According to the characteristics of the wideband digital array radar sampling in the Radio Frequency（RF） part,a real time and efficient digital time delay beam forming method based on the Variable Fractional Delay（VFD） filter is presented.The method proposes that the VFD filter can be integrated with the decimation anti-aliasing filter to design a dual-purpose filter and reduce the processing modules,and the polyphase structure is combined with the Farrow Structure to configure the key filter proposed above.This approach can realize the decimation and variable fractional delay in real time and achieve the accurate beam direction,which isn＇t affected when the signal frequency varies.The computer simulation result shows that,compared with unit delay beamforming approach,this optimized approach can improve the beam pointing accuracy effectively.