Exploiting the real-valued property of modulated signals

such as MASK

BPSK

and AM

and employing the received signals of all the array elements and their conjugate datas

virtual spatial smoothing algotithm is proposed by designing virtual subarrays for the highly correlated or coherent case.Virtual subarrays with

M

identical sensors avoid the reduction of the array effective aperture

and make this approach estimate

M-1

coherent signals at most.Finally simulation results show that comparing with forward-backward spatial smoothing algorithm

this algorithm with small snapshots has a better performance and a low computational complexity to some extent.