An iterative multipath interference canceller with linear equalization for ultra high data rate DS-UWB system

In ultra high data rate carrier based direct-sequence ultra-wideband (DS-UWB) systems with low spreading factor (SF), severe inter-path interference (IPI) and inter-chip interference (ICI) degrade the performance of conventional Rake-Equalizer receiver due to the poor autocorrelation property of spreading code. Moreover, in scenarios with long channel delay spread, the high computational complexity of decision feedback equalizer (DFE) becomes a heavy burden for system design. In this paper, a selective multipath interference canceller (SMPIC) assisted by linear equalization (LE) is developed for practical receiver design, which achieves a better trade-off between performance and computational complexity than Rake-DFE. In this scheme, the SMPIC is capable of alleviating the strong IPI, ICI and inter-symbol interference (ISI) by cancelling out reconstructed multipath interference in an iterative manner. Then a low complexity LE with small tap number is employed. Monte Carlo simulations show that compared with Rake-DFE, the proposed SMPIC-LE receiver, with much lower computational complexity, can achieve similar or even better performance in different UWB channel models.