Zero padded Symmetric Conjugate Self Cancellation Technique in MB-OFDM System Design

UltraWideband (UWB) systems use Multi-Band OFDM (MB-OFDM) techniques for transmission. UWB based systems are power limited by the regulation of Federal Communications Commission (FCC). CP introduces correlation in the transmitted data sequence and hence introduces ripples in the power spectral density (PSD) of the transmitted data. This in turn reduces the range of data transmission. The overlap and add(OLA) method length in UWB receiver depending on the current band of reception and the band wise estimated true FFT window start point. The delay in spread channel model (CM), gain, ICI are not better we can extend this delay spread channel by using Symmetric conjugate technique. The property of symmetric conjugate cancellation is investigated, a technique for ICI is cancelling and diversity combining is proposed. Simulation results show that the proposed scheme achieves a lower bit error rate (BER) compared to the ordinary zero-padded MIMO-OFDM systems in AWGN channel. In Rician fading channels, when frequency offset is 1-10%, the proposed system performance, i.e. BER, is significantly improved over the zero-padded symmetric conjugate self cancellation in MIMO-OFDM systems when the frequency offset is not greater than 10% of subcarrier frequency spacing.