BLIND CHANNEL ESTIMATION FOR MC-CDMA SYSTEMS WITH APERIODIC SPREADING CODES

摘要

This paper develops the blind channel estimation for MC-CDMA systems with aperiodic spreading codes. The channel impulse response plays an important role in the estimate of the transmitted symbol. However, the time-varying effect due to the aperiodic spreading codes makes the channel estimation difficult. The problem is solved by utilizing the second-order statistics of the despreading signal vector to find the channel information matrix of the desired user. It is analyzed that the channel information matrix is unbiased and more efficient than that proposed by Liu in the case of finite samples. With the channel information matrix, the channel impulse response can be estimated by the least-square method. Computer simulations show that the proposed method not only has small mean-square channel information error but also requires fewer computations than Liu's method.