Decision directed recursive least square adaptive channel estimation for OFDMA uplink system

In this paper, we present the decision directed RLS (recursive least square) adaptive channel estimation to improve the channel estimation performance of the OFDMA (orthogonal frequency division multiple access) uplink System. Uplink system shows worse channel estimation performance due to their small channel estimation unit and low SNR (signal to noise ratio). DDCE (decision directed channel estimation) has been used to enhance the channel estimation performance. However the used filter coefficients are not optimized filter coefficient. In practice the exact correlations is difficult to obtain, so we cannot get the optimized filter coefficient. To obtained the optimized filter coefficient, we utilized an adaptive filter algorithm. Especially, RLS adaptive filter used to the estimated correlated has been used to estimate channel estimation. Proposed method improves DDCE channel estimation performance and We initialized the adaptive filter coefficients based on the statistical characteristics of the wireless fading channel.