5G 2.0 (3GPP Release 16) will focus on applications, namely enhanced mobile broadband, ultra-reliable, low latency communications, and massive machine type communications.
The 5G specification, 3GPP Release 15, is now complete and the industry is deploying the world's first 5G networks. The inevitable question is, “What's next?” To that end, let's take a look at the standardization process and what's now being proposed for the next phase of 5G. In the short-term, there are three broad areas of future evolution including new applications and use cases, new spectrum, and optimizations.
3GPP is prioritizing applications and use cases for Release 16. Recall that the 3GPP categorized 5G goals along three distinct classifications: enhanced mobile broadband (eMBB), ultra-reliable, low latency communications (URLLC), and massive machine type communications (mMTC). The 3GPP focused on eMBB initially to address the world's endless demand for faster data.
For URLLC, which proposes to reduce network response time and improve reliability, the 3GPP laid a solid foundation in Release 15. More work is planned for Release 16. For example, mMTC aims to connect millions if not billions of devices. Work on mMTC has continued for some time in the 3GPP through LTE. LTE is predicted to reside alongside 5G networks for the foreseeable future, and the 3GPP views evolutions and enhancements for mMTC in 5G NR after release 16.
In addition to the three pillars described above, several other industries are working with the 3GPP to address their specific needs for inclusion in the standard. For example, the automobile industry requires more connectivity to connect vehicles to other vehicles and vehicles to infrastructure (V2X) to improve safety on the way to realizing adaptive driver assistance systems (ADAS). The V2X Release 16 study item has been completed and the work item is underway.
Satellites are also being discussed in 3GPP. Satellites offer two important benefits to the 5G ecosystem. The first is redundancy. In the case of a catastrophic event where the existing infrastructure is rendered inoperable, satellite communication offers a backup option. Secondly, satellites can extend coverage to areas that lack existing infrastructure or where deploying infrastructure may be difficult, unfeasible, or not profitable. The non-terrestrial networks (NTN) study item has been developed and may be included in Release 17.
As the world becomes more and more dependent on wireless communications, spectrum continues to become a very precious resource. To that end, the 3GPP is investigating several frequency bands in both the licensed and unlicensed regions. The 3GPP capped 5G exploration and deployment in release 15 to below 52.6 GHz, and in future releases spectrum above 52.6 GHz will be considered. Propagation and transmission at these frequencies can address several wireless use cases that are not easily addressed at lower frequencies, and the 3GPP can tailor the definition to the specific requirements for the proposed use cases.
Unlicensed spectrum was considered in prior 3GPP work specifically to address the use of LTE in existing WiFi bands. With 5G, the 3GPP is taking a fresh look at unlicensed frequencies, officially titled NR-U. New unlicensed bands being proposed include the 5 GHz band, the 6 GHz band, and the 57-71 GHz band designated by the FCC for 5G. There are two primary classes of use cases for these unlicensed bands: access assisted and stand-alone. Access assisted enables a 5G user to augment their data rates for specific applications perhaps on a time limited basis. Augmented and virtual reality are examples of applications that could make use of an unlicensed band to improve user experience especially indoor areas where the spectrum may be lightly used. Stand-alone NR-U addresses the request for private or localized networks, where a business or user controls the spectrum usage and can deploy a 5G private system without needing to "share" the spectrum with other unlicensed users. In both cases, the 3GPP must address coexistence and fairness with other users of the spectrum even in a completely private region.
And finally, the 3GPP continues to look for ways to optimize the current standard to improve performance and user experience. In Release 16, there are several proposed optimizations to Release 15 to improve performance through interference management and resource utilization. Examples are the study/work items related to cross link interference and remote interference management and enhancements to MIMO (eMIMO). The 3GPP is also investigating improving battery life in a phone through the UE power optimization study item.
5G is released but not quite done yet as the 3GPP looks to satisfy the requests and demands from a myriad of sources. The transformative goals the industry set for 5G will take some time to realize especially as new and nascent technologies mature. However, the 3GPP foundational elements lay a solid base. Expect some interesting news in the coming months as the collective 3GPP group makes unprecedented progress toward building a global 5G ecosystem.
—James Kimery is the director of marketing for RF, communications, and software defined radio (SDR) initiatives at National Instruments.