"RCoM has informed DoT that it will be upgrading its network from CDMA to LTE (4G) technology using the liberalised 800 Mhz spectrum. It will roll out LTE services progressively in these service areas from May 4," an official source told PTI.

Anil Ambani-led RCom is believed to be leveraging spectrum sharing pact it had signed with his elder brother Mukesh Ambani-led Reliance Jio Infocomm for 4G services. The company will deploy its own 4G network and pre-dominantly use Reliance Jio infrastructure to deliver 4G services.

The DoT in February had approved sharing of active infrastructure like antenna used for transmitting mobile signals in February.

RCom will trade CDMA grade spectrum in 800 MHz band in nine service areas where Jio doesn't have radiowaves. In 17 circles, the two companies has signed spectrum sharing agreement.

RCom has already paid Rs 5,383.84 crore to liberalise its spectrum in 16 circles which include Delhi, Mumbai, Punjab, Himachal Pradesh, UP East and West, Gujarat, Madhya Pradesh, Kolkata and Bihar.

A liberalised spectrum allows telecom operators to use any technology to deliver mobile services like 3G and 4G. Besides, they will be able to introduce new technologies and share and trade it with other operators for its efficient use.

The Cabinet has earlier cleared liberalisation of spectrum -- allocated without auction to telecom companies - at Trai recommended price with the balance being collected after deriving market rate through bidding.

The decision will enable Reliance Communications (RCom) to liberalise its spectrum in four telecom circles, where auction determined price is not available, for Rs 1,300 crore. This circles are Kerala, Karnataka, Rajasthan and Tamil Nadu.