BSNL Chairman Anupam Shrivastava has officially confirmed what had only been hinted at so far, the company will indeed launch 4G services starting with Kerala next month.
However, in all the buzz, one key element of the plan was overlooked — it is going to use Band 1, also known as the 3G band, for its upcoming 4G service.
However, BSNL has only one block of spectrum in this band, which can be used either for 3G or for 4G, but not for both.
In fact, the clue to the puzzle lies in another of Shrivastava’s remarks while making the announcement — “We will initially focus on those areas where 3G coverage is low.”
In other words, the company is going to launch 4G services in rural and remote areas where its 3G spectrum is still lying unutilized and those areas where the usage of 3G is so low that it would be OK to switch it off and divert the spectrum for 4G.
However, the downside of the strategy is that the areas where there is currently no BSNL 3G are also areas where there are few inhabitants, such as hilly areas and near the jungles.
In most other areas — including towns — BSNL is already using the spectrum for 3G.
Given that launching 4G in the hills and jungles is unlikely to be the company’s gameplan, it is therefore likely that it would switch the spectrum from 3G to 4G in at least some of the smaller towns.
This could affect those who are using the company’s 3G service for getting Internet access, as they will have to upgrade to 4G handset or dongle to continue to access BSNL’s high-speed data services.
On a positive note, switching over the spectrum from 3G to 4G will increase BSNL’s data carrying capacity by 2.0-2.5 times without making any other change.
Add to this, the possibility of extra towers being added, the company is likely to see a major fall in the congestion currently seen in its network.
BAND 41
Finally, the company also has Band 41 spectrum (2500 MHz) in Kerala and most other places.
This spectrum too can be deployed, either independently or in conjunction with Band 1, to reduce congestion and increase capacity further.
The addition of Band 41 will increase the capacity by around four to five times compared to a network that depends solely on Band 1. Put another way, compared to the present 3G network, the total bandwidth on such a combined 4G network will be 8 to 12 times.
The company faces two hurdles in carrying out this dual-spectrum strategy — lack of handset support for band 41 and poor penetration levels of the band.
It is estimated that only 2% or 3% of the total 4G handsets and dongles in use in India currently support Band 41. To access the high-speed network, customers will have to either buy new dongles, or purchase new 4G handsets.
The band, however, is likely to be more widely supported in coming days as Idea & Vodafone are also going to launch on Band 41. As such, handset makers will start adding support for the frequency on their handsets soon.
But that is still a few months away.
The decision by BSNL to use 2100 MHz 3G spectrum for 4G — instead of rolling out a Band 41-based network — indicates that the company is aware of the ‘penetration’ and coverage problems associated with the band.
A Band 41 tower is likely to have a penetration and coverage power of only about 70% that of a 2100 MHz tower (see graphic from Sprint above).
To avoid upsetting its 3G users, the company is also working in parallel to get an additional block of Band 1 spectrum. Shrivastava said that it would launch 4G in cities like Bangalore and Hyderabad after it gets the additional spectrum.
This strategy is also aimed at ensuring that the company’s 2G network is not saddled with unbearable levels of load at the time of the introduction of 4G. If it switches off the 3G network to launch 4G, the company’s voice traffic — which is currently carried by 2G and 3G — will be loaded on to the 2G network.
While this won’t be a problem in rural areas, it will create severe call drop problems in places like Bangalore, Chennai and Hyderabad where the 3G network is used to carry a significant amount of the total voice traffic as well.