Performance Analysis of Multiband OFDM UWB Systems With Imperfect Synchronization and Intersymbol Interference

This paper provides performance analysis of MB-OFDM UWB systems that not only captures the characteristics of realistic ultra-wideband (UWB) channels, but also takes into consideration of the imperfection of the frequency and timing synchronizations and the effect of intersymbol interference. The systems are considered in multipath fading channels, the IEEE 802.15.3a channel standard, with four channel models: CM1, CM2, CM3, and CM4. These channel models are characterized by cluster arrival rate, ray arrival rate within clusters, and cluster and ray decay factors. First, an average signal-to-noise ratio with imperfect synchronizations and intersymbol interference is derived. Then a closed-form bit error rate performance formulation that provides insightful understanding of the system performance in various synchronization conditions is obtained under Rayleigh fading assumption. This analytical performance formulation serves as an upper bound on the bit error rate performance of UWB systems. Finally, simulation results under various channel and synchronization conditions are provided to validate the theoretical analysis.