| Transmitted reference (TR) systems have recently gained major attention in UWB communications due to the challenge of channel estimation in indoor environments. TR systems for UWB applications are amenable to inexpensive receiver design. On the other hand, receivers with energy detectors, while suffering from performance degradation, have even more simple implementation techniques which make them cost efficient candidates for inexpensive receivers. In both of these systems, determining the optimum integration interval length at the receiver is a non-trivial task. The optimum integration interval is essential to balancing energy capture versus noise capture. Recently, a diffusion channel model was proposed for the UWB indoor propagation channel. This paper shows that the optimum integration time (in terms of effective SNR of the decision variable to minimize the bit error probability) can be analytically obtained from the diffusion model in a computationally inexpensive method. The method can be implemented with simple analog components, and determines the optimum stopping time for the receiver. As a result, since the stopping time is optimized adaptively for each received channel response, superior performance is achieved with respect to a computationally extensive averaged analysis for a similar objective. Simulation results show a significant performance improvement with simple hardware added to the receiver. |