As the demand for mobile wireless services continues to rise, the telecom industry faces a significant challenge: spectrum scarcity. The spectrum, a limited and finite resource, is becoming increasingly crowded, making the transition from 4G to 5G particularly tricky. A pragmatic and sensible solution to this pressing problem is dynamic spectrum sharing (DSS).
What is Dynamic Spectrum Sharing?
DSS is an antenna technology that permits 4G-LTE and 5G cellular wireless technologies to be used within the same frequency band. This innovative approach allocates bandwidth based on changing levels of usage while minimizing interference, thus maximizing spectral efficiency. DSS allows service providers to share available spectrum, easing the transition from 4G to 5G without lengthy and expensive spectrum reallocation exercises or acquiring separate 5G spectrum.
Technical and Regulatory Complexities
The latest briefing paper from 5G Americas, “Spectrum Sharing: Challenges & Opportunities,” provides in-depth coverage of the various spectrum-sharing models (licensed, unlicensed, and shared) and their technical, regulatory, and economic complexities. While licensed spectrum is the gold standard for 5G networks, spectrum sharing presents a viable alternative as spectrum becomes scarcer, particularly in the low- and mid-band ranges.
Benefits of Spectrum Sharing
Spectrum sharing offers several benefits to the wireless industry and the Americas in particular. DSS, for instance, enhances spectral efficiency by allowing low-priority unlicensed users to share the bandwidth of high-priority licensed users. This technology also supports the simultaneous use of 4G/LTE and 5G New Radio (NR) on the same frequency band, exploiting the flexibility of the physical layer as defined in current telecom standards.
Overcoming Challenges
Despite its benefits, spectrum sharing is technically complex and presents a regulatory challenge. Service providers must ensure that their operations do not interfere with incumbent operators’ established performance and functional parameters. This has historically led to lower efficiency in shared spectrum systems compared to when a single operator has exclusive access to a particular slice of bandwidth.
Dynamic Spectrum Sharing in IoT
DSS plays a crucial role in smart connectivity within the Internet of Things (IoT). Its dynamic nature is particularly appropriate for the diverse IoT systems and networks, ensuring IoT devices have the bandwidth and reliable communication channels necessary for efficient operation. Mobile network operators can leverage DSS to maximize their LTE-M and narrowband IoT (NB-IoT) assets for many years to come, ensuring the coexistence of multiple generations of wireless technologies within the same frequency band.
Motivating Spectrum Holders
Widespread adoption of DSS will depend on motivating existing spectrum holders to share their allocations. This will likely involve financial incentives and the valuation of spectrum sharing, as well as investment in new technologies. Additionally, the administrative and technical costs associated with managing shared spectrum access are considerable, posing further challenges.
The Future of Spectrum Sharing
Despite these challenges, the benefits of DSS make it an essential component of the future of 5G. In an ideal world where spectrum is infinite, exclusive licensing would always be preferred. However, in reality, spectrum sharing encourages new and non-traditional operators to enter the market, fosters innovation, increases competition, and ultimately provides better customer service. Spectrum sharing is also ideal for private networks in various sectors, including agriculture, automotive, energy, and manufacturing.
Chris Pearson, president of 5G Americas, aptly sums up the situation: “Dedicated exclusive-use radio spectrum is a critical resource affecting the wireless industry, economy, and technology leadership. Yet, effective spectrum sharing could be a part of some solutions but will require innovative technologies and collaborative regulatory frameworks to ensure that both legacy users and new entrants can coexist without compromising performance.”
As the evolution of 5G continues, spectrum sharing will play an increasingly important role. While exclusive licensing remains ideal, DSS provides a practical solution to spectrum scarcity, enabling the coexistence of multiple generations of wireless technologies and supporting the growing demands of IoT and other advanced applications. The future of 5G depends on innovative approaches like DSS to overcome the challenges of spectrum scarcity and ensure the seamless transition from 4G to 5G.
