Source Detection Using Bootstrap Technique in Spatial Nonuniform Noise

Consider the problem of source number detection in the presence of nonuniform noise, a new method based on the orthogonality of noise subspace and signal subspace is proposed. Estimate the direction of any incident signal, get eigen-decomposition of the covariance matrix and calculate the inner product vector of eigenvector and the steering array vector. Then a sequential hypothesis test is proposed based on the inner product vector. There is no assumption about on the distribution of the data and the bootstrap is used to estimate the null distribution of the test statistics. Through the simulation it is found that the proposed method is superior to other similar algorithms at small number of snapshots and low signal-to-noise ratio (SNR).