Tiled Array Design for Multi-Beam Joint Communication and Sensing: Channel Matching Method

The integration of sensing and communication capabilities within a single platform is a significant advantage of sixth-generation (6G) communication systems. Multi-beam technology offers an efficient front-end solution for joint communication and sensing (JCAS) at the base station (BS), enabling simultaneous communication with multiple users and sensing multiple targets through analog beamforming. This work introduces a scenario-based tiling array design methodology for a JCAS BS, employing a tiled planar array (TPA) that emphasizes cost-effectiveness, modularity, and scalability. We adopt a low-complexity channel-matching method to optimize the tiles by leveraging self- and cross-correlations of communication and sensing channels. Key performance metrics for this design include the signal-to-interference-plus-noise ratio (SINR) for both communication and sensing tasks. Numerical results indicate that the optimum design of TPAs for JCAS necessitates a proper knowledge of the scenario and environment in which the apertures will be employed. In conflicting scenarios, such as communication operates in non-line-of-sight (NLOS) conditions while sensing relies on line-of-sight (LOS), the scatterers that enable communication also appear as clutter to the sensing function. For example, if NLoS communication clusters fully obstruct the radar targets, the JCAS system can suffer up to a 10 dB drop in sensing SINR; however, these clusters can benefit communication, when the scatterers are positioned in regions of higher aperture gain.