Spectrum Sharing for 5G/6G URLLC: Research Frontiers and Standards

6G communication research is currently in the early stage. A consensus on 6G has been achieved that ultra-reliable low latency communication (URLLC) is still an important application as it is in 5G. The spectrum resources are scarce to support the massive throughput demands, leading to unbearable latency. Also, the collisions in the shared spectrum make the channels unreliable. The problems in unlicensed bands are more severe due to interference among multiple communication technologies. Therefore, it is urgent to design efficient spectrum sharing algorithms to support URLLC in 5G and the emerging 6G. In this article, we explore the related 3GPP standards, recall the recent advances in spectrum sharing algorithms, and analyze the challenges of spectrum sharing in 5G/6G. We also provide potential research fields in future 5G/6G applications.