India has been battling the issue of spectrum scarcity for the past few years. Today, the country has less than a sixth of the quantum of unlicensed spectrum that developed economies across the globe do. To address this scarcity and open up unlicensed spectrum usage, one of the most suitable solutions is the 6 GHz band. According to industry experts, opening this band will increase the amount of spectrum available for Wi-Fi by nearly a factor of three, and help improve rural broadband connectivity in India. Further, delicensing of the 6 GHz spectrum band will help usher in next-gen Wi-Fi technologies such as Wi-Fi 6 and 6E, which can help complement 5G by providing high speed and high capacity broadband services.
However, since there are incumbent users in the 6 GHz band in India, it was felt necessary that coexistence studies be carried out on sharing the entire 1200 MHz spectrum in the band for Wi-Fi usage with the existing users. To this end, the Broadband India Forum (BIF) recently launched a report on “Frequency Sharing for Radio Local Area Networks (RLANs) in the 6 GHz Band in India”. The report highlights the importance of sharing in the 6 GHz spectrum band, its benefits to the economy, and how the band could be optimally utilised to provide Wi-Fi and other innovative services along with the incumbent services already being provided using the band in India.
A look at the key findings of the study…
Background
The study examines the prospective use of the 5.925 to 7.125 GHz band (6 GHz band) in India by licence-exempt devices, such as RLANs. Three different types of RLANs are included in the study – low power indoor (LPI), standard power (SP) (indoor/outdoor) with automated frequency coordination and very low power (VLP) (indoor/outdoor). The three identified classes are based on rules that have been proposed by other regulatory authorities, including the US Federal Communications Commission, Ofcom in the UK and the Electronic Communications Committee of the European Conference of Postal and Telecommunications Administrations.
The report has been prepared by RKF Engineering Solutions LLC, USA. Throughout the study, RKF, along with BIF, analysed the potential impact of licence-exempt RLANs on two types of incumbent users in the band: fixed satellite service (FSS) and fixed service (FS), as the 6 GHz band is shared primarily between two services in India – FSS uplinks and fixed microwave (fixed service or FS) links.
Role of licence-exempt technologies in broadband connectivity
Devices that employ Wi-Fi and other unlicensed standards have become indispensable for providing low-cost wireless connectivity in countless products used by Indian consumers. Licence-exempt technologies are a critical element in delivering broadband connectivity to consumers and businesses. For instance, Wi-Fi is needed to connect devices in a household, or business to a wired or wireless broadband connection. As consumers continue to rely on an increasing number of devices, reliable and fast Wi-Fi connectivity has become essential. Dependency on Wi-Fi has increased manyfold during the Covid pandemic, as almost every erstwhile connectivity requirement (school, office, business, etc.) has moved to homes. However, despite the increasing reliance on licence-exempt technology and the enormous growth in traffic demands being placed on the technology globally, the spectrum allocated for Wi-Fi use remains limited to the 2.4 GHz and 5 GHz bands, as it has been for many years.
The latest Wi-Fi technology, designed for speed, low latency and optimised for use by multiple devices in the same location, uses much wider channelisation to meet the far more intensive broadband needs of consumers and businesses alike. For example, the latest generation of Wi-Fi technology, Wi-Fi 6, can utilise radio channels as broad as 80 or 160 MHz, and a future generation of Wi-Fi technology that is already in development will utilise channels of 320 MHz.
For these reasons, on April 23, 2020, the Federal Communications Committee in the US adopted rules that made 1200 MHz of spectrum available in the 6 GHz band (5.925-7.125 GHz) for licence-exempt use. These new rules will expand licence-exempt broadband operations, promising to bring a wide range of innovative wireless applications to consumers while protecting incumbent users in the band. Further, it is expected that the rules adopted for 6 GHz unlicensed devices will foster the expansion of Wi-Fi hotspot networks to provide consumers access to even higher speed data connections and growth in the internet of things (IoT) industry, connecting appliances, machines, meters, wearables and other consumer electronics, as well as industrial sensors for manufacturing.
Need for 6 GHz unlicensed bands in India
Wi-Fi is the workhorse technology for providing broadband to both consumers and businesses worldwide. At the same time, the industry is on the precipice of technologies that promise more immersive experiences such as virtual reality (VR), high speed gaming and sensor networks, which will require unprecedented amounts of capacity. Proactive planning is important for seamless and rapid adoption of these technologies. To this end, the 6 GHz spectrum, using next-generation Wi-Fi technology, would provide the capacity and flexibility to keep up with the demands of these new applications.
Further, India’s broadband usage has been increasing at an unprecedented rate. Today, India has approximately 792.78 million broadband subscriptions. However, only about 60 per cent of these are unique broadband subscribers. Further, India has less than one-twentieth the amount of unlicensed spectrum that other leading economies have (about 650 MHz versus around 14,000 MHz). Moreover, the existing mobile broadband speeds in India are less than a tenth of global values (average download speed is roughly 18 Mbps, as reported by Open Signal’s August 2021 report). The prevalent situation involves high and rising data usage, unique broadband subscribers being less than 40 per cent of the total population, and a greater propensity for video downloads in rural regions, where literacy rates lag and the population (approximately 65 per cent of the total population) is largely “unconnected” to broadband.
Higher download/offload capacity is therefore crucially required through availability and capacity from Wi-Fi spectrum bands (such as 6 GHz) to complement mobile broadband capacity and speeds. Moreover, proliferation of broadband services in rural areas requires additional spectrum to enable better quality of service, deliver better citizen services such as IoT and cloud services, and facilitate new applications such as wireless mesh-nodes backhaul, video-over-Wi-Fi, wireless mass storage, short-range devices (SRDs) and multi-room augmented reality/VR/gaming. These are all examples of use cases that are only possible using the wider band channels that the 6 GHz spectrum band could provide. In an India-specific use case, there is a much higher need for SRDs in rural India to support the healthcare augmentation required in those areas.
Moreover, newer technologies such as Wi-Fi 6E would only be possible in the 6 GHz band. It would help deliver optimum results in terms of very high throughputs and very low latency, thereby complementing 5G technology through mobile data offload in fixed locations. It would also enable advanced applications such as industrial IoT and private networks, complementing New Radio unlicensed bands. A relevant use case for India would be to support the establishment of sophisticated manufacturing facilities in rural areas, where 6 GHz-based Wi-Fi 6E private networks could play a key role.
Internationally, over 35 countries have chosen to delicence the 6 GHz band, including the US, the UK, Korea, Brazil, the United Arab Emirates, Saudi Arabia and the countries in the European Union. The rationale for delicensing has been to enhance benefits for citizens while reaping the benefits of economic growth in their economies. Notwithstanding the traditional allocation of 2.4 GHz and 5 GHz for unlicensed use, the necessity of expanding bandwidth into 6 GHz to meet growing needs cannot be overstated.
Conclusion
In line with the global experience, the study was undertaken to determine whether RLANs could coexist in the 6 GHz band (in a delicensed manner) in India with the incumbent services, FSS and FS, after providing for due protection to these services. The outcome of the report shows that RLAN Wi-Fi operations in India for all three RLAN device classes (LPI, SP and VLP) in the entire 6 GHz band (5,925-7,125 MHz) will not cause any harmful interference to FSS or FS with regard to point-to-point microwave-linked incumbents. It will also help provide the additional capacity required to complement mobile broadband, to achieve the desired quality of service and ubiquitous broadband connectivity for end users through Wi-Fi.
