Channel Estimation Technique for Amplify and Forward Based Wireless Relay Networks Using BLUE Approach

In this paper, best linear unbiased estimation (BLUE) approach based algorithm is proposed to estimate the overall channel impulse response between the source and destination of amplify and forward (AF) strategy based wireless relay networks (WRN). BLUE is most suitable for practical implementations and can be determined with knowledge of only the first and second moments of the probability density function (pdf). It exhibits the properties of linearity and unbiased. The simulation results show that mean square error (MSE) performance of the channel estimation algorithm using BLUE is better than the conventional least squares (LS) and minimum mean square error (MMSE) based approaches at lower signal to noise ratio (SNR). Cramer-Rao lower bound (CRLB) is derived to validate the MSE performance. The proposed channel estimation algorithm approaches CRLB as the length of the training sequence and number of relays increases.