A Novel Multi-beam Directional Modulation OFDM Waveform Design for Integrated Sensing and Communication

In integrated sensing and communication (ISAC) systems, the simultaneous transmission of communication information and radar sensing waveforms presents significant challenges, in particular with regard to interference management. This paper proposes a novel orthogonal frequency division multiplexing directional modulation waveform (OFDM-DM) design for ISAC systems, which effectively enhances communication security while eliminating interference. In the proposed ISAC waveform scheme, multiple OFDM-DM beams can be synthesized, enabling the system simultaneously sensing multiple targets. The scheme can securely transmit information toward multiple target directions while concurrently acquiring vital target information, such as range, relative velocity, and azimuth. Theoretical analysis and simulation results demonstrate that the proposed OFDMDM waveform not only preserves the integrity and security of communication signals but also enhances sensing accuracy by reducing sidelobe interference. This work represents a significant advancement in the design of waveforms for ISAC systems, offering a promising solution for future ISAC networks.