Hybrid Beamforming Design for Wideband Near-Field ISAC with Delay Alignment Modulation

This paper studies a multi-user integrated sensing and communication (ISAC) system with delay alignment modulation (DAM) in the near-field. We aim to optimize multi-path hybrid beamforming so as to maximize the signal-to-noise ratio (SNR) of the target echo while ensuring communication users' signal-to-interference plus-noise ratio (SINR) requirements and transmit power budget. To this end, we propose an alternating optimization algorithm using successive convex approximation (SCA) technology, penalty convex-concave procedure (PCCP) and second-order cone programming (SOCP). Simulation results demonstrate the effectiveness of the proposed algorithm and show the impact of channel model mismatch and the distance dimension introduced by the near-field model on the near-field DAM-ISAC system.