A Comprehensive Survey of ISAC Technology: Fundamental Principles, Research Progress, and Future Trends

Abstract

Traditional wireless communication and sensing systems have long been separated, lacking synergy in spectrum, hardware, and signal processing, which leads to low resource utilization and high costs. With the evolution from 5G-A to 6G, the demand for "communication-sensing-decision" integration has surged in scenarios such as intelligent transportation, and traditional architectures can hardly meet this demand. The integrated sensing and communication (ISAC) technology, which realizes functional integration by sharing spectrum, hardware, and algorithms, has become a core direction in breaking through the bottleneck. Its research popularity has risen rapidly in the past five years, but the achievements in the field are scattered and lack systematic sorting. This paper aims to construct a panoramic review of ISAC, expound its technical principles, sort out research progress and breakthroughs, summarize development trends, and consider current challenges and prospects. This effort will integrate scattered research results, establish a systematic ISAC technical knowledge system, provide references for practical implementation, and point out future directions for researchers.