Energy-efficient relay-assisted THz V2X networks with integrated sensing and communication

Terahertz (THz) V2X networks with integrated sensing and communication (ISAC) face severe blockage and energy constraints in urban environments. This letter studies relay-assisted communication with vehicle-side sensing QoS constraints. We formulate a joint beamforming optimization problem to minimize power consumption under strict communication and sensing constraints. An efficient iterative algorithm utilizing Matrix-Extended Generalized Lagrangian Dual Transformation (MEGLDT) and Block Coordinate Descent (BCD) is developed. Simulations demonstrate that the proposed scheme yields significant power savings compared to benchmarks, particularly in high-density scenarios. These findings validate the framework’s scalability and efficacy for next-generation V2X applications.