5Gi - How Viable is it To Go for India's Own 5G Standards?

After successfully clearing all the demands, ITU cleared 5Gi for use as a 5G Standard in November 2020. This was the first time any Indian Telecom Standard was adopted as an official standard, so the excitement it generated was justified. However, does the need of the hour demand it?

5Gi - A Brief Refresher

The International Telecommunications Union accepted 5Gi as a 5G standard on 23rd November, 2020. For those unaware, Telecommunications Standards Development Society, India, is the Indian equivalent of 3GPP in Europe, the organization that develops global telecom standards.

ITU approved only 3 5G standards, including normal 5G, roaming and 5Gi.

Keeping in mind that India is a large country , and many people live here , to the rest of the world, it seems like an obvious step. And a step in the right direction to boot. There are obvious incentives in this situation. Countries with similar conditions to India’s might also see benefit in a big cell size standard. The question remains of interest.

Is there enough interest from vendors and researchers in supporting 5Gi?

How will 5Gi Work?

The standard takes in account the load on Indian telecom sector and uses a waveform that provides more range. Indian research institutes such as IIT Hyderabad and IIT Madras developed this high-range waveform.

The new network operates in so-called "cells" - a region which a 5G transmitter can cover. Since 5G relies on waves with higher frequency (starting from below 700 MHz to 52,000 MHz), it sacrifices range.

Therefore, it will most probably rely on lower end of the 5G spectrum, up to 36 GHz at most. The DoT has made this much obvious - they plan to schedule a spectrum auction in the coming months.

In March 2016, ITU drafted up a list of requirements for a 5G standard, under their project called IMT-2020.

In November 2020, IMT-2020 recommended 3 key 5G components:

1. 3GPP 5G-SRIT: Developed by 3GPP Proponent as 5G, Release 15 and beyond − LTE+NR SRIT
2. 3GPP 5G-RIT: Developed by 3GPP Proponent as 5G, Release 15 and beyond − NR RIT
3. 5Gi RIT

5Gi RIT - India's Answer to 5G

TSDSI RIT is a versatile radio interface that fulfils all the technical performance requirements of IMT 2020 across all the different test environments. This RIT focuses on connecting the next generation of devices and providing services across various sectors. In particular, this RIT focuses on:

1. Enhanced spectral efficiency and broadband access,
2. Low latency communication,
3. Support millions of IOT devices,
4. Power efficiency,
5. High speed connectivity,
6. Large Coverage (in particular for Rural areas),
7. Support multiple frequency bands including mmWave spectrum.

While, the current specifications provide a robust RIT, the specification also provides a framework which can support future improvements. Therefore, these specifications provide a future-proof technology.

Key Features of 5Gi RIT

Here are some of the key features which make 5Gi compatible with the Indian telecom sector. These are only a few of the features of this specification. I have highlighted these as they show this network's compatibility with the Indian Telecom situation.

MIMO Support

This set of telecom standards was made with India's telecom situation in mind. The RIT supports large-scale massive MIMO deployments. That is beneficial as it allows for better network coverage and capacity. Crucially, if a 5G network is to operate on sub-6GHz and mmWave spectrum bands, it needs MIMO support. Incidentally, this specification supports both those bands.

This specification also supports multiple points for transmission and reception. For example, it supports coordinated multiple point transmission, multiple antenna panel transmissions, among others. These help avoid blockages in higher frequencies and improve reliability.

URLLC Support

URLLC, or Ultra-Reliable and Low Latency Communication, is what its name suggests it is. It is useful in places such as smart factories, along with industry automation and smart cities.

In terms of reliability, 5Gi's specification can achieve a reliability of 99.9999%. What's more, the control plane and user plane have assured latencies less than 10 ms and 1 ms, respectively.

URLLC will be crucial in future 5G applications and will define how large-scale production works in the coming decade. More importantly, that means having a network compatible with URLLC will prove vital for automation and IoE, eventually.

Energy Efficient Network

The network has many power-saving features. First, when there is no active data transfer between the network and the UE, the network saves power. It does so by remaining on for a while, after which it goes to sleep. Second, the on duration consists of transmission of SSB with PBCH, RMSI and paging signal which needs to be monitored by UEs. Third, during the sleep duration, there is no transmission or reception to/from the UE.

Support for NBIoT

The specifications support mMTC applications via NBIoT. It is a narrow band technology which is used in applications such as ATMs and so on.

NBIoT supports 200 kHz bandwidth with 1 PRB scheduling. NBIoT also works to increase the coverage significantly by means of scheduling multiple TTIs for every physical channel transmission.

It supports mainly three modes of transmissions – in-band, guard band and standalone. This support makes it flexible.

Telcos Have Reservations Regarding 5Gi

India's Big Telco - Bharti Airtel, Reliance Jio and Vodafone Idea all seem to reject the idea of 5Gi as a mandatory 5G standard in the country. Not only them, telecom vendors such as Nokia, Ericsson, Huawei, Samsung, and NEC want that either 5Gi be compatible with 3GPP's global 5G standards, or be discretionary.

Reliance Jio supports the local standards, but believes that it should be compatible with global standards. On the other hand, Bharti Airtel recently said that this could lead to an "existential threat", locking India out of the global ecosystem.

There are still a lot issues and that could result in a costly, error-prone and very delayed 5G launch. This incompatibility can cost India and Indian telcos in the long run.

Incompatibility with Global 5G Standards

SP Kochhar, DG, COAI, talked about these issues recently. "Issues relating to interoperability of the proposed (5Gi) specification with the global 3GPP specification still remain", he said. Kochhar also said that there are no established performance gains over 3GPP's standards, adding that local standards should be discretionary.

Interestingly, 5Gi focuses on enhancing rural coverage, but becomes tunnel-visioned, as there is no compatibility with 3GPP standards. TSDSI failed to conduct further research to create compatibility.

However, TSDSI have something to say about that. NG Subramaniam, Chair, TSDSI and COO, TCS, said that 5Gi will be "a game-changer for the telecom service providers". He also said that in addition to being very much viable for the wider coverage and other technical enhancements provided by this standard over 3GPP technology, it can also be implemented by software changes.

Telecom Industry and TSDSI - A Love-Hate Relationship

TSDSI developed India's first actually accepted telecom standard for 5G. Along with 3GPP's two standards, 5Gi was the third standard in February 2021.

However, the industry says that it has no interoperability with 3GPP 5G. That means that telcos will bear the brunt of costing due to technology and infrastructure demands of the standards. Deploying the same will only delay the 5G rollout.

However, TSDSI said that most of the changes in 5Gi are software based. As such, that won't require any changes at the hardware level.

TSDSI also said that it will keep the standard updated, and will bring out a roadmap soon.

In this regard, DoT sides with TSDSI, seeking to make the standard mandatory for all operators. However, the industry feels that it will mean the entire phonemaking initiative of the government and industry would go in vain.

Kochhar said that TSDSI needs to look how 5Gi can evolve to adapt to 3GPP's standards. He further added that the telcos must make the choice between 5Gi and 3GPP and not the government. COAI further said that it will support technologies compatible with existing global standards.

"We believe that there are no specific challenges and also dialogue among relevant stakeholders is on," Subramaniam added.

Foreign Lobbying for 3GPP?

In February this year, the Global mobile Suppliers Association (GSA) president Joe Barrett wrote a letter to India's Telecom Engineering Center. In the letter, he sought the adoption of 3GPP's recent specifications as national standards.

Multiple GSA members were "already in advanced planning stages" with Indian telcos for 5G rollout, as per Barrett.

In January, Bharti Airtel and Vodafone Idea, along with Qualcomm, Nokia, Ericsson, Huawei, Samsung and NEC, wrote a letter to TEC. In that, the group said that the 3GPP based products are already incorporated in the regulatory requirements for conformance testing with statutory and certification bodies worldwide.

It seems fishy, but they do make a solid argument. 5Gi's weakest point is a lack of future planning. Sort that out, and TSDSI sorts India out with a solid standard to last the decade.

Wrap Up

It is clear that 5Gi serves as a great achievement for Indian telecom sector. TSDSI have done a good job in covering most of their bases. However, the fact remains that 5Gi is incompatible with 3GPP's 5G standards. It will take several reiterations to fix that issue, but it is doable.

5Gi supports key technology such as NBIoT and URLLC, both of those are crucial for the IoT industry in the country. The nation's 5G network requires a solid foundation in a carefully-chosen standard. 5G Testing officially began yesterday, and the time is nearing for the industry to make the choice.

Should India choose to go with 5Gi, there will be bumps on the way, but at the end, it will be all worth it.

One thing is certain - 5Gi is only the start for India's contributions to the global telecom industry.