Performance Analysis and Optimization of $\hbox {T}_{\rm c}$ -DTR IR-UWB Receivers Over Multipath Fading Channels With Tone Interference

In this paper, we analyze the performance of a particular class of transmitted-reference receivers for impulse radio ultrawideband communication systems, which is called chip-time differential transmitted-reference ( T_c-DTR). The analysis aims at investigating the robustness of this receiver to single-tone and multitone narrowband interference (NBI) and comparing its performance with other noncoherent receivers that are proposed in the literature. It is shown that the T_c-DTR scheme provides more degrees of freedom for performance optimization and that it is inherently more robust to NBI than other noncoherent receivers. More specifically, it is analytically proved that the performance improvement is due to the chip-time-level differential encoding/decoding of the direct sequence (DS) code and to an adequate design of DS code and average pulse repetition time. The analysis encompasses performance metrics that are useful for both data detection (i.e., average bit error probability) and timing acquisition (i.e., false-alarm probability P_fa and detection probability P_d ). Moving from the proposed semianalytical framework, the optimal code design and system parameters are derived, and it is highlighted that the same optimization criteria can be applied to all the performance metrics considered in this paper. In addition, analytical frameworks and theoretical findings are substantiated through Monte Carlo simulations.