A source enumeration method based on subspace orthogonality and bootstrap technique

A new method is proposed for sources number detection in array signal processing. This method is based on the orthogonality of signal subspace and noise subspace. At first obtain a set of bootstrap snapshots from original snapshots. Then estimate the direction of an arbitrary incident source, make eigen-decomposition of the covariance matrix and compute the weighted inner product vector. Subsequently repeat the above procedures many times to get weighted inner product vectors and calculate the average of them. Finally employ a clustering algorithm to determine the number of sources. The simulation results show the superiority of the proposed method at small number of snapshots and/or low signal-to-noise ratio (SNR).