Vodafone India, the country's No 2 carrier, will unveil 4G services in Mumbai by December 2015, setting the stage for an aggressive war with market frontrunner Bharti Airtel and Mukesh Ambani's Reliance Jio Infocomm.

The Indian unit of UK's Vodafone Plc has been financing the development of 4G services and testing has been successfully initiated. The company said it has already spent over Rs 500 crore in rolling out over 1,000 sites in Mumbai.

Vodafone India will use the FDDLTE standard for its upcoming 4G services in Mumbai by using the 1800 MHz band, which is more popular 4G band worldwide than the 2300 MHz airwaves that Bharti Airtel has to use for 4G services. It is well known that 1800 MHz spectrum provides superior in-building coverage than TDDLTE airwaves in the 2300 MHz band.

Vodafone has collaborated with a leading global technology infrastructure service provider for the 4G network launch, but didn't name its partner.

With around 30% of data revenues, Mumbai "is one of the top data markets" for Vodafone in India. To further fortify this position, Vodafone is spending heavily on high capacity fibre/backhaul to considerably increase internet connectivity.