How 5G tech could be a game-changer for India

The reserve price will be 1.5 times for spectrum allocation for 30 years. It suggested a 36% cut in reserve price for 3,300-3,700 band compared to what it suggested in 2018. For the 700 MHz band it suggested a reduction of 58%

Prime Minister Modi inaugurated the country's first 5G test bed on May 17, 2022, the world Telecom and Information Society day. This was set up at a cost of Rs 220 crores and it was developed by eight institutes led by IIT Chennai. This test bed will enable startups and industry players to test and validate their 5G products locally. This facility will be available at five different locations.

On May 19, Telecom Minister successfully tested India's first 5G VoNR (Voice over New Radio) audio and video call for which the entire end to end network has been designed and developed in India at IIT, Chennai.

Indigenous 5G technology

The indigenous 5G technology (5Gi) is one of three 5G technologies approved by ITU (International Telecommunication Union) as a 5G standard. This has been designed by IIT Chennai, IIT Hyderabad and the Centre of Excellence in Wireless Technology. It works at a lower frequency. This operates on the Large Cell Low Mobility (LCLM) principle. This technology supports higher cell size coverage (up to 12 km radius) which is the requirement for serving the rural areas. This higher coverage reduces the requirement of the number of base stations. In this technology, the battery set will have a long life. This technology is supported by Telecommunications Standards Development Society of India (TSDSI). 5Gi technology requirements have been merged with 3 GPP (3rd Generation Partnership Project) 5 G standards in January 2022.

All communications on a 5G network are encrypted with keys stored in the core implying that they can't be read by the base station. This makes the core critical from a data security point of view. Government wants TSPs to adopt the Indian core for 5G network.

Attractive point in 5G technology

Attractive point in 5G technology is that the same network will be able to deliver the three different categories of use cases namely:

1. e MBB (Enhanced Mobile Broadband)

2. m MTC (Massive Machine Type Communications)

3. U RLLC (Ultra Reliable Low Latency Communications)

This is possible because of the following features of 5G:

1. NFV (Network Function Virtualisation): NFV, by virtualising network infrastructure, separates the functions that typically run in hardware and implement them as software

2. SDN (Software Defined Network): It allows administrators to control and change the network remotely.

3. MIMO (Multiple Input Multiple output): Technology that uses multiple transmitters and receivers to transfer more data at the same time.

4. Network Slicing: It is a network configuration that allows multiple networks to be created on top of a common physical infrastructure.

TRAI recommendations on auctioning of spectrum for 5G

On April 11, TRAI released recommendations on the auction of 5G spectrum. The available spectrum in existing bands 700 MHz, 800 MHz, 900 MHz, 1800 MHz, 2100 MHz, 2300 MHz, 2500 MHz and new bands 600 MHz, 3300-3670MHz and 24.25-28.5 GHz are recommended to be put for auction.

1. Reserve price for various spectrum bands for 20 years

TRAI has recommended reserve price for various spectrum bands (for 20 years), service area wise. The reserve price will be 1.5 times for spectrum allocation for 30 years. It suggested a 36 per cent cut in reserve price for 3,300-3,700 band compared to what it suggested in 2018. For the 700 MHz band it suggested a reduction of 58 per cent.

2. Co-existence of 5G service and satellite service for efficient use of spectrum

TRAI recommended that the frequency band 27.5 -28.5 GHz (Ka band) should be used for 5G as well as Satellite Earth Station Gateways (Earth to space communication) by proper coordination between DOT and DOS. This will lead to efficient use of spectrum which is a limited natural resource.

But DOT is considering auctioning of spectrum only upto 27.5 GHz as sharing between the two services is difficult as per DOT. The final decision will be taken by the cabinet. It is hoped that the Cabinet will ask for the inclusion of this 27.5 GHz to 28.5 GHz band also in the auction. Reserving this spectrum only for Satellite service will lead to inefficient use of spectrum. With the technology advancements, both these services can coexist and TRAI in its recommendations mentioned various mechanisms to achieve this coexistence.

Similar coexistence of 6GHz/4GHz LOS (Line of Sight) microwave links along with satellite systems, operating in the same frequency bands, is there world over with some restrictions on both sides. The mm wave spectrum is very valuable to TSPs (Telecom Service Providers) as this band supports high bandwidth with high data speed for serving smaller, densely populated areas.

As the network deployment in mm wave band for 5G will not be ubiquitous and will be kind of hotspots, urban microcells and Fixed Wireless Access (FWA), coordination to avoid interference between 5G and satellite service will be possible. The non auction of this band will make this spectrum unutilised because of non-readiness of Space broadband players apart from loss to exchequer. It is hoped that the Cabinet will accept the TRAI recommendation in this regard.

3. Various options for providing 5G solutions to Enterprises

The regulator has recommended that all options should be made available to enterprises for their 5G solutions which are as follows:

1. Captive network for the enterprise can be set up by the TSP using Network Slicing from TSP's network.

2. TSP can establish an independent private network in an enterprise's premises using TSP's spectrum.

3. Enterprise may get spectrum on lease basis from TSP and establish its own Captive Wireless Private Network (CWPN).

4. It may obtain spectrum directly from the government and establish its own CWPN for which the government has to earmark spectrum to be assigned directly.

Digital Communication Commission (DCC) has decided not to allow direct spectrum allocation to enterprises to establish captive private 5G networks. The Cabinet has to take a final call on this issue.

If TRAI's recommendation on direct spectrum allocation to enterprises on administrative price is implemented, the TSPs will lose enterprise business revenue and it will make the 5G business unviable to them as they have to depend only on retail customers for the revenue. TSPs participate in the auction process, bid for the spectrum and make huge investments in purchasing it. They have domain expertise in planning and operation of mobile services. As DOT rightly decided, only TSPs should be allowed to offer enterprise solutions to corporate entities and enterprises should not be allotted spectrum directly. It is hoped that the Cabinet will endorse DOT's decision in this regard.

4. Additional Frequency bands

TRAI recommended that DOT should coordinate with the Ministry of Information and Broadcasting (MIB) for the vacation of 526-582 MHz spectrum for migration of their transmission from analogue to digital. This spectrum provides deeper and wider coverage for 5G. After this spectrum is vacated by MIB, it will be included in the auction for 5G. It also recommended that DOT should liaise with ITU etc for development of regional band plan for 526-612 MHz.

Infrastructure challenges for the TSPs for 5G implementation

1. For giving 5G services in densely populated areas, TSPs need to deploy small cell technology which will increase the network capacity. Small cells use mm wave frequencies which can cover only small distances. They can be deployed on street furniture like utility poles, billboards, lamp posts, traffic signals, bus stops and multiple antennas are required to serve a specific area. The TSPs have to coordinate with the street furniture owners in this regard.

2. Without good backhaul, the advantages of 5G can't be fully exploited. Optical Fibre (OF) is the ideal choice for 5G backhaul. Currently only 33 per cent of towers are connected with fibre. TSPs have to achieve at least 70 per cent of fiberisation of towers to utilise the full potential of 5G. Getting ROW (right of way) clearance for laying OF cable is a challenge in some states. Aerial fibre may have to be laid on street furniture for connecting small Cells. Laying OF in hilly terrains (like North East Region) is another challenge. In the NE region satellite connectivity can be used as backhaul. However if GSO based satellite connectivity is used, high latency (240 m sec) and low capacity are the challenges which will nullify the advantages of 5G. If LEO based satellite connectivity is used, these issues will be addressed. In other regions also, all sites may not be accessible on fibre. Using E band (71-76 GHz, 81-86 GHz) or V band (57-64 GHz) wireless system is another option. TSPs require access to E band and V band spectrum and provision of adequate spectrum bands with wider channel sizes in these bands. Using Integrated Access and Backhaul (IAB) is another solution in which backhaul uses the same 5G radio resources of Access (connectivity to user equipment, UE).

Way forward

The 5G network rollout will add Rs 35 lakh crores to the Indian economy, increasing the pace of development and creating jobs. It will bring positive changes in the governance of the country, ease of living and Ease of Doing Business (EoDB). Agriculture, health, education, infrastructure and logistics sectors will have boosted growth. It is hoped that spectrum auctions will be conducted successfully after the clearance from Cabinet and 5G services will be rolled out before the end of 2022. DOT has already selected MSTC (Metal Scrap Trade Corporation) as the auctioneer for the upcoming auction. Government is considering assignment of spectrum to BSNL/MTNL for 5G service.

(The author is a former Advisor, Department of Telecommunications (DoT), Government of India)