On the Rate-Exponent Region of Integrated Sensing and Communications With Variable-Length Coding

TL;DR

This paper analyzes the rate-exponent region for integrated sensing and communication systems using variable-length coding with feedback on Gaussian channels, revealing a trade-off between sensing and communication performance.

Contribution

It introduces a novel analysis of the rate-exponent region with feedback-based variable-length coding, differing from prior fixed-length coding studies.

Findings

Three achievable regions are analytically derived.

Numerical evaluations demonstrate the impact of feedback on the rate-exponent trade-off.

A fundamental trade-off between sensing and communication is established.

Abstract

This paper considers the achievable rate-exponent region of integrated sensing and communication systems in the presence of variable-length coding with feedback. This scheme is fundamentally different from earlier studies, as the coding methods that utilize feedback impose different constraints on the codewords. The focus herein is specifically on the Gaussian channel, where three achievable regions are analytically derived and numerically evaluated. In contrast to a setting without feedback, we show that a trade-off exists between the operations of sensing and communications.