Least-squares (LS) method is widely used for multipath channel estimation. The conventional algorithms for computing the LS solution involve matrix inversion, which is computationally demanding. In this paper, by exploiting the special structure of Toeplitz matrices, a fast and memory-saving numerical algorithm is developed for calculating the LS estimate of a multipath channel. The proposed fast channel estimation algorithm is easy to implement and has a low computational complexity of $O(N\log N)$ with $N$ the received signal length. Simulation results are provided to verify the performance and computational efficiency of the proposed fast LS algorithm.
['Xue Jiang', 'Wen-Jun Zeng', 'En Cheng', 'Congren Lin']
Multipath Channel Estimation Using Fast Least-Squares Algorithm