Improved blind channel estimation method with Toeplitz displacement for long code DS-CDMA

This paper proposes an improved blind channel estimation scheme for long code DS-CDMA systems with multipath fading channel. We first exploit the statistical properties of the autocorrelation matrix obtained from the received signal after matched filtering. Then the Toeplitz displacement method is applied to the autocorrelation matrix to remove the effects of channel noise and interference before the correlation matching approach is adopted to estimate the channel parameters. The method requires only the knowledge of the desired spreading code and its properties. Simulation results show that the proposed method can achieve a better MSE performance and be more robust against the near-far problem.