Airtel launched 4G for smartphones in Calcutta with a blitzkrieg of advertisements in newspapers, but their service has turned out to be woefully inadequate with calls not going through to the LTE (long term evolution) enabled phone.

It took them over 12 days to activate the 4G nano SIM on a brand new iPhone 5c, but the connection remained at 2G. There was no sign of the “electrifying Internet browsing experience anytime, anywhere” promised by Airtel. After running around from pillar to post and several phone calls, three engineers took over five hours to finally identify the problem and fix it. First the problem was blamed on the SIM and then on the Apple device but it turned out to be a configuration issue on the backend computers that control the towers.

4G LTE is a technology that delivers blazing fast Internet on mobile devices that support it. One of the biggest problems with Airtel’s LTE technology is that your phone will default to 2G for calls, and to the slower EDGE for Internet connectivity when the signal is poor, which seems to be the norm in Calcutta. However, when the signal was strong I got speeds up to 20 Mbps.

If you are on roaming, you will get the LTE signal only in Bangalore, Pune and Chandigarh. For all other states you will be switched to 2G even if Airtel has 3G network there. Why would anyone pay a premium for such poor service when other operators are offering better phone and data connectivity on their 3G networks?

If you take a 4G connection in Calcutta, be prepared to remain incommunicado in many areas of the city. Airtel uses a circuit switched fallback technology for all voice calls as the 4G LTE version it has adopted, called Time Division Duplex, on 2300 MHz is only for Internet connectivity. For calls, it switches to 2G but fails to do it seamlessly. Whether you are calling the LTE phone from an Airtel, Aircel, or Vodafone number, you will often get a message saying, “This facility is not available on your telephone. Contact Airtel customer care…” Obviously there are still many glitches in its service that, strangely, has not been ironed out despite LTE being operational in three other cities in India.

If you do want to try out an LTE connection, take the SIM from a big Airtel shop, such as the one on Park Street. Make sure the device you are using supports 4G LTE TDD (Time Division Duplex) on the 2300 MHz spectrum. Currently, on Airtel’s LTE network only the iPhone 5s (model A1530), iPhone 5c (model A1529), Xolo LT 900 and LG G2 (model D802T) will work. Unfortunately, the new iPad Air and iPad mini will not work on Airtel’s 4G networks because Apple shipped the wrong model to India. Till the time of going to press Apple did not officially respond to queries on why this happened.

If you live in an area where there is an LTE signal but you are not getting it on your device, first contact Airtel’s Customer Care at 121/198 or 121@in.airtel.com. If that does not resolve your problem send a mail to nodalofficer.wb@in.airtel.com or call 9831234865 between 9:30 am and 6:30 pm Monday to Friday. If you live in another state you will find the relevant email address at www.airtel.in/applications/xm/MobileNodalOfficer.jsp. Your problem should be solved at this stage. But if you are still not satisfied take it to the appellate authority at appellate.wb@in.airtel.com or call this team at 9831844865, between 9.30 am and 6.30 pm on weekdays.

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