A novel DOA estimation algorithm based on the largest eigenvalue of the covariance matrix is presented.It mainly applies to the pencil beam smart antenna in DS-CDMA systems.Different from other DOA estimation algorithms

it only picks up the main path signal of the target user.Thus it can get a high resolution with lower computational requirements.Theoretical analyses and simulation results show that this method has quite good stability and robustness

especially under severe multipath propagation circumstances.