Optimal Channel Energy Capture for Ultra-Wideband Transmitted Reference Systems in Clustered Channels

Due to the large signal bandwidth of an ultra-wideband (UWB) transmitted reference (TR) system, the clustering channel statistics, as defined in the IEEE 802.15.3a channel models, should be taken into account in performance characterization. In this paper, we address the optimal mean channel energy capture for the maximal signal-to-interference-plus-noise ratio (SINR) regarding the special UWB channel statistics. It is analytically shown that a simple receiver that captures a fixed ratio of the mean channel energy can perform quite well, which is valid universally for non-line-of-sight channels and a generic class of TR systems. For line-of-sight channels, it is noticed that optimal SINR may be achieved at an integration time approaching zero, revealing a new interesting phenomenon. The channel conditions under which the phenomenon tends to happen are also provided. Furthermore, we characterize the channel conditions suitable for different TR systems.