Wideband DOA Estimation with Interpolated Focusing KR Product Matrix

Qinghua Liu, Liangnian Jin, Shan OuYang
2015 International Journal of Signal Processing, Image Processing and Pattern Recognition  
A new direction-of-arrival estimation method for uncorrelated wideband sources is proposed. Firstly, the covariance matrices of different frequency bins are transformed into higher dimensional vectors through Khatri-Rao product to produce the new models of the array outputs. Secondly, the higher dimensional noiseless signal subspace at each frequency is focused to a certain reference frequency and a single correlation matrix is constructed, where the focusing matrices are designed by
more » ... igned by interpolating the virtual steering matrices of the new model. Finally, the DOA estimates are acquired through using narrowband MUSIC method. The proposed method is able to increase the degrees of freedom of a uniform linear array and enable us to handle more sources than sensors. Numerical results demonstrate the performance of the proposed method. Because the spatial resolution is limited to the aperture of array, in order to improve the spatial resolution and even resolve more sources than sensors case, the virtual array structure should be constructed to increase the degrees of freedom of array. Lately, a Khatri-Rao (KR) product was proposed to expand the array structure [8] . The extended array is similar to the virtual array established by the higher order cumulant method [9] [10] . After excluding the overlapping elements in the virtual array structure, the number of virtual sensors can reach 21 N  , approximately 2 times of the actual array elements We apply the -J point discrete Fourier transform (DFT) to each segment and combine the components from each segment at the same frequency point, write the output of the array as
doi:10.14257/ijsip.2015.8.3.18 fatcat:fu6re3lrinfbzkcqefkktourz4