OFDM channel estimation and equalization using multi scale independent component analysis

Present day wireless communication systems require a high data rate wireless access, for which the prerequisite is larger bandwidth. Obviously, to mitigate the inter symbol interference (ISI) caused by the multipath fading of high data rate communication system is orthogonal frequency division multiplexing (OFDM). The major challenging task in multiple input multiple output (MIMO) OFDM systems is to design a good channel estimation method with less computational complexity and lower value of bit error rate (BER). Here, a novel signal processing method based on combining the advantages of multi-scale property of wavelet transform (WT) with blind estimation capability of independent component analysis (ICA), called, a multi-scale ICA (MS-ICA) has been proposed to estimate the channel characteristics. The MS-ICA method can effectively identify the channel impulse response under unknown channel conditions i.e. blindly. Performance of the proposed MS-ICA method is evaluated by calculating the BER for different fading channels. As compared to other well known OFDM channel estimation methods the proposed MS-ICA method resulted in a lower value of BER, which indicates the superiority of the proposed method.