Monostatic ISAC Without Full Buffers: Revisiting Spatial Trade-Offs Under Bursty Traffic

TL;DR

This paper examines how bursty traffic affects spatial trade-offs in monostatic ISAC base stations, revealing key effects on detection probability, SNR, and target masking, guiding more efficient transmission strategies.

Contribution

It provides a comparative analysis of ISAC policies under bursty traffic, highlighting the impact of non-full-buffer conditions on performance trade-offs and system design.

Findings

Data-aided strategies boost SNR compared to pilot-based ones.

Detection probability saturates due to bursty traffic conditions.

Directional masking affects sensing based on target and user positions.

Abstract

This work investigates the spatial trade-offs arising from the design of the transmit beamformer in a monostatic integrated sensing and communication (ISAC) base station (BS) under bursty traffic, a crucial aspect necessitated by the integration of communication and sensing functionalities in next-generation wireless systems. In this setting, the BS does not always have data available for transmission. This study compares different ISAC policies and reveals the presence of multiple effects influencing ISAC performance: signal-to-noise ratio (SNR) boosting of data-aided strategies compared to pilot-based ones, saturation of the probability of detection in data-aided strategies due to the non-full-buffer assumption, and, finally, directional masking of sensing targets due to the relative position between target and user. Simulation results demonstrate varying impact of these effects on ISAC trade-offs under different operating conditions, thus guiding the design of efficient ISAC transmission strategies.