Recently, integrated sensing and communication (ISAC) techniques have gained significant attention due to their ability to simultaneously perform sensing, localization, and communication using shared wireless resources and signal waveforms, thereby enhancing spectral and cost efficiency. Orthogonal frequency division multiplexing (OFDM) is also expected to remain a key technology in next-generation mobile communication systems due to its robustness against multipath fading and its strong support for high data rates. Building on these points, we propose a novel orthogonal sequence (OS)- based OFDM-ISAC technique fully compatible with conventional OFDM-based communication systems. This technique intelligently exploits the autocorrelation properties of OSs and the spectral efficiency of index modulation while incorporating a clustering algorithm to address challenges in multipath environments. Extensive computer simulations verify that the proposed OFDM-ISAC system delivers reliable communication and localization performance in realistic multipath environments. even in the absence of a line-of-sight (LOS) link.
This work was supported in part by the Institute for Information and Communications Technology Planning & Evaluation (IITP) Grant funded by the Korea Government (MSIP, Development of Cube Satellites Based on Core Technologies in Low Earth Orbit Satellite Communications) under Grant RS-2024-00396992 and in part by the MSIT(Ministry of Science and ICT), Korea, under the ITRC (Information Technology Research Center) support program (IITP-2024-RS-2024-00436406) supervised by the IITP.
