Performance evaluation of Decision-Directed (DD) channel estimation using diversity techniques

Channel estimation is a one of important technique to improve the performance of Orthogonal Frequency Division Multiplexing (OFDM), and the Decision-Directed (DD) channel estimation is focus on this paper because of the ability of decreasing bit error rate (BER) in the OFDM performance. Decision-Directed channel estimation based on least square error (LSE) was suggested, and it is conducted in the both white Gaussian noise channel and multipath Rayleigh channel. By implemented channel estimation, the OFDM system deals with other problem which is an effect in channel fading due to complexity. Various diversity techniques are used in OFDM system in order to combat the effects of channel fading and to improve the system performance. Diversity can be implemented in three different domains namely time, frequency and space. The simulation result shows that the Decision-Directed channel estimation adapted with diversity scheme improved the performance of OFDM system in terms of increasing SNR and decreasing BER.