New Delhi, July 12: Country's top telecom operator Bharti Airtel is working on a war footing to get its 3G network running across the entire country on the highly efficient 900MHz spectrum by September as it seeks to ward off the looming threat of Reliance Jio, which will offer 4G by the end of this year.

A substantial part of Airtel's $2.2-billion capital expenditure, earmarked for this fiscal, will be used for 3G. The operator will also not be shy of additional investments to ramp up its 3G network if it gets its targeted "revenue growth".

"We are going to roll out 3G networks aggressively over the first six months of this year and we will then decide if we need to put more capex, which will not be a constraint if we are actually getting the revenue growth we seek," Gopal Vittal, joint managing director and CEO-India & South Asia, had said at a conference call on the company's earnings for the year ended March.

Following spectrum auctions in March, Airtel now has 3G spectrum in 21 of the country's 22 circles, combining both 900MHz and 2100MHz bands, barring Kerala. Earlier, it had high-speed radiowaves only in 13 circles and was offering 3G services in other circles through agreements with other operators.

The company also plans to phase out its intra-circle roaming (ICR) pacts with the other operators by the end of this year and deploy premium 3G over the 900MHz band in 10 circles within the next 1-2 years.

Under the roaming agreement, Airtel was not allowed to add subscribers in circles where it did not hold 3G spectrum.

The company has already launched 3G in the 900MHz band in Mumbai and Calcutta, under the Platinum 3G brand.

"With the launch of Platinum 3G, Airtel customers can browse the Internet 122 per cent faster than any other 3G network, get 36 per cent better indoor coverage and enjoy extended battery life. Additionally, users can stream videos 144 per cent faster than the existing speed," Ravindra Singh Negi, CEO (Bengal & Odisha), said

The company has over 4 million customers in Calcutta and over 5 million in Mumbai, out of which around 20 per cent are smartphone users who use 3G to browse the Internet and download data.

Bharti Airtel expects the more efficient 900MHz 3G service to lead to subscriber additions and an increase revenue from high speed data services. Nilanjan Roy, CFO-India and South Asia, said, "(The company can be) much more aggressive in the market once we have our own spectrum and own sites, so I think definitely in terms of 3G revenue this should be a push for those gap circles."