A NEW METHOD TO CHANNEL ESTIMATION IN OFDM SYSTEMS BASED ON WAVELET TRANSFORM

In OFDM systems, it is necessary to estimate the channel to overcome the distortion caused by channel fadinga€ s which can be induced by many phenomena such as: delay spread, multipath effect, mobility and Doppler shift. Most of the channel estimation techniques are proposed in frequency domain using the pilot symbols. One of them which has less complicated is well-known as Least-Squares (LS) method which is widely used in channel estimation but it is more sensitive to noise respected to the other reported techniques. In this paper, a new threshold based method using wavelet decomposition will be proposed which is based on an initial LS estimation technique. The reported simulation results show that the proposed method has better performance compared to the other methods such as Lee Method that has been published recently.