Abstract: MB-OFDM UWB communication technology use orthogonal UWB pulse sequence and multiple sub channels to achieve reliable high data rate transmission and spectral efficiency. In this paper, we followed the standard proposal IEEE 802.12.3a to implement the MB-OFDM UWB system in Matlab simulink. We analyzed the system performance in the multipath fading channel, using S-V channel model. We evaluated the bit error rate for LOS & NLOS channels. We used fixed-point simulation platform which is constructed according to MB-OFDM scheme proposed by MB-OFDM Alliance and the compensation scheme is based on phase compensation.