| NOTAS: | "New spectrum is increasingly more difficult to secure than it was for prior generations of mobile networks. It is now more important than ever that all available spectrum can be efficiently utilized. While radio spectrum can be licensed for the exclusive use of a single operator,an operator may share licensed spectrum with multiple other operators. Shared use of spectrum among multiple operators can lead to better utilization of spectrum without the constraints associated with non-exclusive use of spectrum, resulting in economic benefits for operators and end users alike. Unlicensed spectrum may be used by anyone as long as the access rules are followed. In general, unlicensed spectrum, while essentially designed to enable spectrum sharing, is often unsuitable, or at least very challenging for operator use due to relatively low power limits and sensing requirements leading to inability for operators to manage KPIs for service quality. 3GPP standardized RAN sharing is a method for operators to share equipment and spectrum while maintaining the same service quality associated with the exclusively licensed spectrum. The downside is that a very high level of cooperation is required among cooperating operators for planning, equipment selection, siting, and operation. The result is less room for operators to differentiate their services and the ability to upgrade, balance, or enhance the equipment is less agile. Finally, 3GPP RAN sharing is not as amenable to sharing between operators and non-operator networks (e.g., Private Networks, government networks, non-3GPP incumbents, ...).A framework based on sharing O-RUs among system operators for spectrum sharing, which builds upon the O-RAN Open Fronthaul’s innate shared O-RU capabilities, addresses many of these limitations and the drawbacks associated with unlicensed spectrum or 3GPP RAN sharing. Power limits can be relaxed, and quality of service can be controlled. The result is a user experience that is comparable to the exclusively licensed spectrum deployments. A “neutral host” like deployment of an O-RU can support shared use from multiple independent O-DUs accessed dynamically via standardized fronthaul interfaces. This can support differentiation between operators. In addition, it retains for MNOs and Private Networks alike all of the cloud-based, complete, centralized control capabilities of the Open RAN system. This includes all of the functionality of the O-DU, O-CU, RIC, and advanced network automation capabilities inherent in the O-RAN architecture. A shared O-RU architecture relies on prioritized use of resources to guarantee service quality and allows statistical multiplexing of traffic among operators, private networks, and other spectrum stakeholders, resulting in more efficient overall use of spectrum resources. In order for such a scheme to work effectively for all of the cooperating spectrum users, the improvement in efficiency is critically dependent on how fast the shared O-RU procedure to allocate idle resource among spectrum users is. The proposed shared O-RU spectrum sharing framework is applicable to sharing between spectrum users including public, private, and government. Additionally, it is radio technology agnostic, i.e., not all of the cooperating systems need to deploy the same 3GPP radio technology versions, and non-3GPP radio technologies can potentially be accommodated using the same O-RAN Open Fronthaul-based shared O-RU mechanisms. Shared O-RU with spectrum sharing feature can create opportunities for new spectrum for the next generation networks. In addition, it can lead to sustainability improvements and reduction to CapEx and OpEx for operators." |
