一种基于虚拟阵元的超波束形成方法

A Hyper Beam-forming Method Based on Virtual Array Element

针对超波束形成方法(Hyper Beam-forming,HBF)在实际应用中的不稳定问题,依据阵元间协方差矩阵同一斜对角线上不同元素具有相同相位差的特点,提出了一种基于虚拟阵元的超波束形成方法(Hyper Beam-forming Based on Virtual Array Element,VAEHBF)。该方法按互相关法对接收阵进行虚拟扩展;按HBF思想分子阵分裂波束形成;对分裂波束形成结果进行合成,得到改善的超波束形成结果。数值仿真和实测数据处理结果表明,相比HBF方法,该方法通过对接收阵进行虚拟扩展,在保持分辨力不变的情况下,可进一步提高合成波束增益,对信噪比的适应能力得到了3 dB提高,提高了HBF的目标检测性能及方位估计能力。

For the instability problem of hyper beam-forming in low signal to noise,according to the characteristic that the same oblique angle of the covariance matrix of array elements receiving signal has the same phase difference,a hyper beam-forming method based on virtual array element is proposed.Firstly,virtual extension of array element was acquired by cross correlation method.Then the split beam formation is achieved according to the idea of HBF.Lastly the synthesized beam is obtained,and the improved results are acquired.The results of numerical simulation and measured data processing showed that,compared to HBF method,VAE HBF improves the synthesis gain of output beam in the case of keeping the resolving ability through virtual extension for receiving array,improves the adaptability for signal to noise ratio more than 3 dB,and has better performance of detecting target and DOA estimation.