<FONT face=Verdana>This paper investigates the direction-of-arrival (DOA) estimation of coherent sources with conjugate cyclostationary properties. A virtual array-based forward backward spatial smoothing method is proposed. By properly applying multiple lag conjugate cyclic correlation functions of specified sensor outputs

a virtual array is constructed first. Based on which

the spatial smoothing technique is then introduced to estimate the DOAs of all the signals of interest. Theoretical analysis and experimental results demonstrate that

compared with the FBSS-based Conjugate Cyclic MUSIC and Conjugate Cyclic Hankel Approximation method

the proposed algorithm not only avoids the optimal lag choosing problem

but also achieves better performance in estimation accuracy. Besides

this method is robust against the difference in signal DOAs. In addition

the proposed method can also be applied to the signals with cyclostationary properties.