Multiuser UWB Communication Systems with Code-Multiplexed Transmitted Reference

Recent studies have investigated alternative methods to the realization of the transmitted reference scheme in UWB communications. In addition to the conventional system, in which data and reference are separated by a time shift, two other methods have been proposed in which the separation is achieved through a frequency offset (FO) or code multiplexing (CM). Their advantage over the traditional system is both in performance and receiver implementation. In this paper they are compared in a multiple access environment. It is shown that the CM-based scheme outperforms its FO-based counterpart and is simpler to implement.