Technology evolution has been a cornerstone of the wireless industry since its inception. While many industry players feel the scale of change has accelerated with 5G (more revolution than evolution), the 8-10 year cycle of new generations of wireless technology has been relatively stable. As part of this pattern, innovation within generations has been critical in enhancing user experience and network performance as generations improve and also accelerating the deployment on new generations with a high degree of future compatibility baked in.
‘Half-Generation’ technologies have generally been the ones to really deliver on the expectation (and hype) of their ‘parent’ generation. As industry players talk up the promise of a new generation, the first launches can often disappoint and it takes years of innovation and standards work to really meet the initial lofty goals of a new technology. I remember my first 3G phone in the UK in March 2003 offered download speeds of 100-150kbps. The UMTS network could theoretically achieve 384kbps and even that theoretical maximum was a slight stretch on the ITU’s IMT-2000 minimum speeds for 3G of 384kbps in a moving vehicle and 2Mbps for stationary or walking users. It really took 3.5G HSPA and HSPA+ to make Mbps mobile Internet use a reality. The same is equally true of 4G, where the looser 4G term covered LTE but the ITU actually designated LTE-Advanced as the IMT-Advanced 4G technology. LTE-Advanced, and perhaps most importantly carrier aggregation and wideband radios supporting MIMO, enabled operators to deliver high-performance mobile broadband networks at scale, delivering on LTE’s original promise.
5G is following a similar path. It is perhaps delivering on the enhanced mobile broadband (eMBB) vision of 5G. Speed test results (such as OpenSignal’s March 2022 Benchmarking the Global 5G Experience) show that where operators have access to sufficient spectrum, leading 5G markets are experiencing average download speeds of 200-400Mbps and peak speeds of 600-900Mbps. This is a significant improvement on the real-world experience of the majority of 4.5G users though for the average smartphone user there are still relatively few mainstream use cases where moving from a 30-50Mbps 4.5G connection to a 200-400Mbps 5G connection is that impactful. When we broaden out to look at the other elements of the 5G vision, of ultra-reliable low-latency communications (URLLC) and massive machine-type communications (mMTC), current 5G deployments that are still mainly focused on non-standalone 5G have yet to really address these markets.
Momentum is growing around 5G Standalone in 2022, which will unlock more of the promised potential of 5G, but it is perhaps 5.5G in the form of 5G-Advanced (3GPP Release 18) that will expand out the set of opportunities for 5G operators. Release 18’s content was agreed by 3GPP in December 2021 with the standard freeze scheduled for December 2023 and potential network launches by 2025. At its Global Analyst Summit in April, Huawei provided an interesting update on 5.5G’s key technology elements and what a 5.5G network can deliver for operators. It introduced it’s ‘1+1+N’ concept consisting of:
- 1: a 1 Gbps foundation network layer, leveraging mid-band spectrum assets (e.g. C-band) to deliver ubiquitous gigabit connectivity for HD video and evolving eMBB use cases;
- 1: a 10 Gbps experience layer, leveraging new spectrum in ultra-wide blocks to deliver multi-gigabit connectivity for AR/VR and 360o video services, the metaverse, digital twins, and other real-time interactive services;
- N: infrastructure to support 100 billion connections, super-charging use cases requiring network-based sensing, high-precision positioning, high-capacity uplinks and ultra-low latency, mainly deployed as hotspot solutions such as campus networks.
There is clarity in this positioning of 5G-Advanced that brings to life more of the promise of the IMT-Advanced eMBB/URLLC/mMTC triangle that preceded 5G launches. Strategy Analytics has been impressed by the rate of development of 5G to date, though the evolution to a truly service-oriented architecture and ecosystem approach has been slower to emerge as speeds and capacity have dominated market evolution so far. There clearly always needs to be performance gains with new technology releases, though it is encouraging to see the need to link these more closely to use cases, whether those be leaps in user experience that will make services like VR/AR more ‘real’ or whether those be capacity and latency gains, such as gigabit uplink, that make enterprise-grade services like digital twins truly business-ready.
For some operators, the capacity gains will be a driving factor in 5.5G adoption as they look to enable a multitude of use cases with ever-improving per-bit efficiency. The evolution of massive MIMO antennae will play a crucial role here, both to support the current evolution and build-out of 5G for the 1 Gbps foundation layer and also to enable the ultra-high capacity ‘super-connectivity’ layer in higher-traffic zones. Huawei outlined work on antenna design that has already seen the 2021 unveiling of its MetaAAU antenna unit that supports 384 antenna elements and it believes 5.5G networks will see antennae move towards 1,000 elements. These extremely large antenna array M-MIMO (ELAA-MM) units should continue the coverage, performance, and efficiency gains already seen as the industry moves beyond first generation massive MIMO antennae.
New spectrum will also be key here and arguably some of the promise of 5.5G depends on designation of the 6 GHz band for mobile use at WRC-23. 6425-7125 MHz could be a priority band for 5.5G, providing sufficiently wide allocations per operator to allow operators to fully exploit the capabilities of 5G-Advanced this decade.
5G-Advanced has the potential to live up to the achievements of other ‘half-generation’ technologies and deliver on 5G’s full vision. It offers a wide range of feature enhancements that will allow operators to effectively build URLLC and mMTC businesses and accelerate eMBB opportunities in a way that 5G has perhaps not delivered to date. It will require a clear focus on technology innovation and execution, coupled with regulatory bodies delivering on spectrum, over the next two years, though the potential offered for the second half of this decade is significant.