The Trade-off between Processing Gains of an Impulse Radio UWB System in the Presence of Timing Jitter

TL;DR

This paper analyzes the balance between pulse combining and spreading gains in impulse radio UWB systems, considering timing jitter, multiple-access interference, and multipath effects, providing theoretical and simulation insights.

Contribution

It offers a comprehensive theoretical analysis of the trade-offs between processing gains in impulse radio UWB systems under various interference and jitter conditions.

Findings

Optimal system parameters depend on timing jitter and interference levels.

Pulse-based polarity randomization affects system robustness.

Simulation results validate the theoretical expressions.

Abstract

In time hopping impulse radio, $N_f$ pulses of duration $T_c$ are transmitted for each information symbol. This gives rise to two types of processing gain: (i) pulse combining gain, which is a factor $N_f$, and (ii) pulse spreading gain, which is $N_c=T_f/T_c$, where $T_f$ is the mean interval between two subsequent pulses. This paper investigates the trade-off between these two types of processing gain in the presence of timing jitter. First, an additive white Gaussian noise (AWGN) channel is considered and approximate closed form expressions for bit error probability are derived for impulse radio systems with and without pulse-based polarity randomization. Both symbol-synchronous and chip-synchronous scenarios are considered. The effects of multiple-access interference and timing jitter on the selection of optimal system parameters are explained through theoretical analysis. Finally, a multipath scenario is considered and the trade-off between processing gains of a synchronous impulse radio system with pulse-based polarity randomization is analyzed. The effects of the timing jitter, multiple-access interference and inter-frame interference are investigated. Simulation studies support the theoretical results.