Integrated Sensing and Communication in the Finite Blocklength Regime
Homa Nikbakht, Michèle Wigger, Shlomo Shamai, H. Vincent Poor
TL;DR
This work analyzes a point-to-point ISAC system operating over a discrete memoryless state-dependent channel in the finite blocklength regime. It derives achievability and converse bounds on the rate-distortion-error tradeoff and characterizes the second-order rate-distortion-error region, using a symbolwise optimal estimator for the channel state. Numerical results on a binary channel with multiplicative Bernoulli state show that the proposed joint ISAC design significantly outperforms time-sharing baselines. The findings illuminate finite-blocklength limits for ISAC and guide practical joint design under latency-constrained scenarios.
Abstract
A point-to-point integrated sensing and communication (ISAC) system is considered where a transmitter conveys a message to a receiver over a discrete memoryless channel (DMC) and simultaneously estimates the state of the channel through the backscattered signals of the emitted waveform. We derive achievability and converse bounds on the rate-distortion-error tradeoff in the finite blocklength regime, and also characterize the second-order rate-distortion-error region for the proposed setup. Numerical analysis shows that our proposed joint ISAC scheme significantly outperforms traditional time-sharing based schemes where the available resources are split between the sensing and communication tasks.
