While C-Band (3.5 GHz) spectrum has been the one most commonly used globally for 5G network launches and most frequently supported by 5G devices, mid-band spectrum more generally can often fulfil a sweet spot of sufficient bandwidth to support high-capacity services and good propagation characteristics to allow strong coverage profiles. Across spectrum bands in the 2-3 GHz range, there is growing momentum for 5G services, either as an alternative to C-Band (where this has not been licensed for 5G) or as a complement. T-Mobile USA’s 2.5 GHz 5G network layer is an impressive example here, offering solid network performance to 225 million people (out of the 315 million total 5G population coverage across all its bands).

For many operators globally, the 2.6 GHz band (B7 for FDD and B38 for TDD) is the core 4G LTE capacity layer. By contrast, the 2.3 GHz band (B40/n40) has a patchier global footprint both in terms of licensing and in terms of network deployments across either 4G or 5G. Where it is in use for 5G, the results are impressive, and Strategy Analytics would like to see more activity in this band. This involves greater licensing of the band and greater use for 5G by existing licensees.

2300-2400 MHz was added as a 5G band (n40, mirroring 4G’s B40) with 3GPP Release 15. For 5G services the band has a number of benefits:

• Good signal propagation allowing operators to deploy at existing sites rather than requiring any meaningful densification of network assets;
• Typically, 90-100 MHz of spectrum that is often assigned to one or two operators, providing good bandwidth per operator for broadband services (in some markets, as a legacy from the WiMAX era, the spectrum is held in 30 MHz blocks for fixed applications);
• An option for mobile broadband spectrum licensing in markets where the C-Band is not currently available (often due to satellite use).

According to the GSA’s latest 5G ecosystem information, there are 73 licensed operators in the 2.3 GHz B40/n40 band, excluding regional CBRS PAL licences in the USA. The number of countries with 2.3 GHz licences is expected to increase from 49 currently to 55 by year-end. The device ecosystem is maturing well, with n40 supported on one in three of announced 5G devices compared to less than one in four a year ago, and n40 support from flagship models down to sub-$300 smartphones. Dual connectivity EN-DC support is also improving in the band, for example the iPhone 12 only offered EN-DC support for n40 with the B28 (2.6 GHz) LTE band, but the iPhone 13 supports EN-DC in B1, B3, B7 and B28.

Where services have been commercially launched in 2.3 GHz, there is currently more activity for 4G LTE, but momentum is certainly growing for 5G. The Asia-Pacific region is perhaps the most developed, with high-volume markets including China (currently used for in-building 4G coverage), India and Indonesia all having active operators at 2.3 GHz, though again the current use is mainly 4G.

There are a number of interesting 5G case studies in the 2.3 GHz band currently:

Brazil: the 5G spectrum auctions in November 2021 replaced a mix of 20-40 MHz regional licences with two licences (40 and 50 MHz) in most regions. The big three operator – Vivo, TIM, and Claro – all won licenses in the auction that also covered 700 MHz, C-Band and mmWave spectrum. Benefits of the 2.3 GHz band in Brazil include it offering a good dual-band NR combination with C-Band for high-capacity locations, allowing operators to initially deploy 4G LTE and evolve to 5G as they require, and accelerating mid-band 5G launches in regions where C-Band spectrum has not yet been cleared. This is a model that is appealing to other countries in Latin America where C-Band is not yet available.

Telkomsel, Indonesia: holds 30-50 MHz in the band (depending on region) and has used this to supplement 4G services. By April 2021, the 2.3 GHz band had grown to account for over 30% of 4G traffic carried by Telkomsel. In May 2021, Telkomsel launched 5G in the band across high-capacity zones in nine cities. Where it can utilize 50 MHz for 5G Telkomsel can deliver over 1 Gbps throughput and it is targeting smart office applications as a key use case here.

Optus, Australia: has up to 98 MHz in the band (depending on region, mainly in cities), which has been a key part of its 4G network since 2012, enabling it to offer high-performing FWA services, now serving over 200,000 FWA customers. In early 2020, Optus launched dual-band 2300 / 3500 MHz 5G in a number of cities, contributing to it recording the fastest 5G download speeds in Australia. 23% of devices on Optus’s network supported 5G in March 2022 compared with 14% of Telstra’s customers on 5G at the end of 2021, and growth in 5G has contributed to a healthy evolution in Optus’s FWA business (half-year revenue to end March 2022 up 13% and ARPUs up 14%).

Telkom, South Africa: has been using 87 MHz of 2.3 GHz spectrum to provide 4.5G LTE-A fixed wireless access services since 2015. This network enjoyed explosive growth in 2016-19 as migration away from ADSL, and underlying growth in broadband connections, benefitted Telkom’s LTE FWA product (growing from 77,000 in March 2016 to 518,000 in March 2018, 80% of total broadband growth) and it retains a market leading position in the fixed wireless market today. Telkom was a modest bidder in the recent 5G spectrum auctions, spending less than half its main competitors to acquire 20 MHz of 800 MHz and 22 MHz of C-Band spectrum, in the knowledge that its strong 2.3 GHz holdings will be an important part of its planned 5G network.

The 2.3 GHz band represents a relatively untapped opportunity for 5G operators today. As the demand for mid-band spectrum increases it is band that would benefit from regulatory attention to ensure that spectrum is both made available for mobile broadband services and is held in sufficient bandwidth (ideally no more than two licences in the band) to deliver high-capacity services. There have been encouraging developments in device availability for the n40 band and in integrating 2.3 GHz into existing 5G networks and it is important that governments play their part to allow operators to make use of this key resource.