Beamforming Design Optimization Utilizing Frequency-Controlled Arrays for Terahertz Near-Field Integrated Sensing and Communication

In this paper, a novel integrated sensing and communication (ISAC) scheme with frequency diversity technique for near-field terahertz (THz) system is proposed by applying different carrier frequency offsets to each transmitting array element of the terahertz array, which introduces an additional distance dimension and provides new design freedom for the THz near-field ISAC system as compared to the conventional system. Various beamforming design strategies under different conditions are also discussed in the scenarios involving multiple users and targets. By integrating the frequency diversity techniques, the proposed scheme demonstrates effective target detection. The weighting factors are also adopted to balance radar and communication performance and the optimization method is proposed. Simulation results validate the effectiveness of the proposed beamforming design strategy.