Capacity of BICM Using (Bi-)Orthogonal Signal Constellations in Impulse-Radio Ultra-Wideband Systems

TL;DR

This paper analyzes the capacity of bit-interleaved coded modulation with (bi-)orthogonal signals in impulse-radio ultra-wideband systems, focusing on the power-limited regime and providing analytical expressions for energy efficiency and system design insights.

Contribution

It provides analytical capacity expressions for BICM with (bi-)orthogonal signals in wideband regimes, highlighting the impact of BICM restrictions compared to coded modulation.

Findings

Derived capacity expressions for BICM in wideband regime

Quantified energy per bit to noise spectral density ratio

Provided design guidelines for impulse-radio UWB systems

Abstract

Bit-interleaved coded modulation (BICM) using (bi-)orthogonal signals is especially well suited for the application in impulse-radio ultra-wideband transmission systems, which typically operate in the power-limited regime and require a very low-complexity transmitter and receiver design. In this paper we analyze the capacity of BICM using (bi-)orthogonal signals with coherent and noncoherent detection and put particular focus on the power-limited or wideband regime. We give analytical expressions for the ratio energy per bit vs. noise power spectral density in the limit of infinite bandwidth and the respective wideband slope, and thus, are able to quantify the loss incurred by the restriction to BICM in contrast to coded modulation. The gained theoretical insights allow to derive design rules for impulse-radio ultra-wideband transmission systems.