On the Performance Tradeoff of an ISAC System with Finite Blocklength
Xiao Z. Shen, Na Zhao, Yuan Shen
Abstract
Integrated sensing and communication (ISAC) has been proposed as a promising paradigm in the future wireless networks, where the spectral and hardware resources are shared to provide a considerable performance gain. It is essential to understand how sensing and communication (S&C) influences each other to guide the practical algorithm and system design in ISAC. In this paper, we investigate the performance tradeoff between S&C in a single-input single-output (SISO) ISAC system with finite blocklength. In particular, we present the system model and the ISAC scheme, after which the rateerror tradeoff is introduced as the performance metric. Then we derive the achievability and converse bounds for the rateerror tradeoff, determining the boundary of the joint S&C performance. Furthermore, we develop the asymptotic analysis at large blocklength regime, where the performance tradeoff between S&C is proved to vanish as the blocklength tends to infinity. Finally, our theoretical analysis is consolidated by simulation results.