Abstract: The consideration of Enhanced Covariance Matrix Technique(ECMT) in DOA estimation for coherent signal sources using large-scale array is discussed and introduced in the paper. This technique is to reduce the noise power contribution to the covariance matrix so as to enhance the signal to noise ratio at reception. It's found in our simulation and analysis that the technique can achieve high resolution in resolving coherent signal sources and closely spaced signals. The simulation results are given to validate the consideration.