Abstract
The densification of 6G networks for integrated sensing and communication (ISAC) demands a comprehensive framework to jointly evaluate sensing performance and electromagnetic field (EMF) exposure. In this paper, we introduce a novel analytical model for downlink ISAC. Specifically, we first derive a closed-form expression for the beamforming gain under sensing beam misalignment at a maximal ratio combiner (MRC) receiver. Building on this result, we then characterize both the marginal and joint distributions of the sensing signal-to-interference plus noise ratio (SINR) and the associated EMF exposure. Our numerical results validate the analytical findings and shed light on the fundamental trade-offs inherent in ISAC network design, providing three key insights: (i) there exists an optimal base station (BS) density, approximately λ b = 3×10 −5 BS/m 2 , that maximizes joint performance, cautioning against uncontrolled densification; (ii) the sensing-communication power allocation provides a flexible control mechanism to navigate the trade-off; and (iii) the advantages of large antenna arrays are highly sensitive to beam alignment, as misalignment losses can offset potential gains and increase EMF exposure. The provided statistical characterizations and design guidelines offer essential tools for the sustainable design of EMF-aware ISAC networks.