Channel identification using known symbol guard intervals

Abstract

Block transmission systems with guard intervals usually either use a cyclic prefix or introduce a sequence of zeros of length greater than or equal to an upper bound of the channel memory between blocks to prevent inter-block interference. Another possibility is to transmit known symbols in the guard interval. Although this has been considered before, the proposed channel identification algorithm was computationally intensive. We propose a simpler algorithm based on first order statistics. At the receiver, the channel is estimated by first computing the mean of the relevant parts of the received blocks. To enhance the performance at high signal to noise ratio, we combine the first order stat..