Joint MEC and ISAC Design in HetNets with SIM-Aided Wireless Backhaul

This work focuses on the integrated sensing, communication, and computation (SCC) for Internet of Vehicles (IoV) in wireless-backhaul heterogeneous networks (HetNets). The wireless backhaul performance of HetNets is typically limited by constrained capacity and severe interference. To address these challenges, stacked intelligent metasurfaces (SIM) is introduced into the wireless-backhaul HetNets. In the SIM-assisted IoV HetNet SCC system, a multi-objective optimization problem is formulated with the objectives of minimizing computation offloading energy consumption and maximizing the sensing beampattern gain of vehicular terminals (VTs). An alternating optimization framework is proposed to jointly optimize VTs computation offloading, SIM passive beamforming, sensing and communication precoding, and mobile edge computing (MEC) resource allocation. Simulation results demonstrate that the proposed scheme effectively balances energy efficiency and sensing performance, achieving significant improvements in both overall energy efficiency and sensing capability compared with conventional approaches.