A Novel High Data Rate Prerake DS UWB Multiple Access System: Interference Modeling and Tradeoff Between Energy Capture and Imperfect Channel Estimation Effect

摘要

A novel high data rate (HDR) Prerake DS UWB multiple access system is proposed, in which the number of taps in the Prerake filter is set to a large value while keeping the number of taps in a chip sufficiently small. Thus high data rate can be achieved via superposition of the chip waveforms, where the inter-chip interference introduced is small due to signal energy focusing. We derive the higher order moments of Multiple Access Interference (MAI) and fit the distribution of MAI using a generalized Gaussian distribution. Numerical results show that the generalized Gaussian distribution is a more appropriate statistical model for the distribution of MAI than the Gaussian distribution. Using the characteristic function (CF) method, an accurate BER formula is derived and validated by numerical results. The effect of imperfect channel estimation is discussed in detail. We highlight that under imperfect channel estimation, there is a tradeoff between the signal energy captured and the channel estimation noise introduced.