Quantifying the Degradation of Combined MUI and Multipath Effects in Impulse-Radio UWB

摘要

We study pulse-based ultra wideband (UWB) communications over multipath channels using asynchronous spread spectrum (SS) multiple access (MA) based on time-hopping (TH) and pulse position modulated (PPM) signals. More specifically, we analyze the signal-to-interference (SIR) degradation in the presence of additive white Gaussian noise (AWGN), multi-user interference (MUI), and dense multipath effects (DME) with line-of-sight (LOS) and non-line-of-sight (NLOS). In particular, we define a degradation margin factor for the combined MUI and multipath effects and also find an expression for the maximum number of simultaneous radio links Nu in terms of the operating SIR, the SS processing gain, and the bit transmission rate Rb. We consider both cases with perfect and imperfect power control.