This paper addresses the performance evaluation of the contemporary UWB WPAN standard. The basic standard functionality is described for which a system model is derived that accounts for the possible errors due to the background noise. Two realistic scenarios of the saturation conditions and the Bernoulli packet arrivals are considered to calculate the system throughput and the mean initial packet delay. The redundancy-based error detection mechanism that is implemented in the standard is discussed that allows the enhancement of the system performance. The obtained results are compared against the simulation which shows a good accordance with the analytical results and a distinct superiority of the introduced enhancement.