Spectrum Harmonization Towards 6G: A Survey

The fifth generation (5G) and beyond mobile communication systems and wireless networks are presently at an advanced stage of deployment around the globe. While 5G provides new services and improved quality of seamless connectivity among various networks, further improvements in this arena in the form of 6G and beyond wireless and mobile communication networks are also being pursued through meticulous R&D activities. Global spectrum harmonization plays a pivotal role in development of these technologies. International standardization and regulatory agencies, global partnerships along with the relevant leading industries play a key-role in this process, forming the back-bone of the technology standards. The continuous process of global harmonization and standardization of frequency and spectrum generates ample amount of technical documentation in the form of white papers, recommendations, study reports, specifications and regulations. These documents are generally lengthy and have enormous amount of vital information. Some of the detailed frequency regulations and specifications are available freely; while some are available in a restricted manner. As per knowledge of authors, there is bare availability of any such concise documents highlighting the process of frequency spectrum harmonization and current global spectrum allocation scenario in context of beyond 5G and 6G. The present article aims at bridging this gap by presenting a comprehensive and compact portrait of frequency regulations and harmonization process applicable for existing and future wireless mobile communication networks like beyond 5G and 6G. This article is a survey paper that essentially provides information on frequency spectrum harmonization and allocation mechanism; international regulatory and standardization bodies, their organizational structure, inter-organization coordination and their working. In addition, the subject of how key technical requirements of existing 5G, beyond 5G and upcoming 6G networks influence the global frequency spectrum policies has been discussed. Paper also surveys recent scenario of global frequency spectrum allocations for 5G, beyond 5G and 6G networks.