Airtel on Saturday officially rolled out 4G LTE trials in the Mumbai on Band 40, 2300MHz using the TD-LTE technology. The company has previously rolled out its 4G services in 23 other cities and over the weekend, it has also added Chennai, Hyderabad & Vishakhpatnam along with Mumbai to its list.
Existing and New Airtel customers with 4G compatible mobile handsets can upgrade their existing SIM cards to newer 4G U-SIMs for Free by visiting any nearest Airtel gallery or by ordering one from their website at http://airtel.in/4g. You can also check whether your handset & SIM are ready for the 4G network by visiting this page and entering your mobile number there.