Abstract
This thesis proposes a space-time selective RAKE (SRAKE) receiver (in cascade form and in joint form) by maximizing signal to interference-plus-noise ratio (MSINR) for ultra-wideband (UWB) wireless communications in the presence of narrowband interference (NBI) and multiple access interference. For effectively extracting the UWB signal of interest with low complexity, two finger assignment strategies (FASs), the energy-based FAS (EB-FAS) and the constrained energy-based FAS (CEB-FAS), are also proposed together with the proposed space-time MSINR-SRAKE receiver. By some simulation results, we show that the proposed space-time MSINR-SRAKE receiver can provide larger system capacity and better immunity to the strong NBI than the existing time-only SRAKE receivers and space-time SRAKE receivers with maximum ratio combining (MRC) when the EB-FAS is used. On the other hand, through analyses and simulation, we demonstrate that the space-time MSINR-SRAKE receiver using the EB-FAS is susceptible to the impact of NBI, and the receiver performance is severely degraded when a strong NBI is present. On the contrary, the space-time MSINR-SRAKE receiver using the proposed novel CEB-FAS outperforms that using the EB-FAS when NBI is the dominant interference, and is much robust against NBI.