I've had such a leased connection; albeit from Reliance. They will likely use an outdoor 2.5ghz AP (so just like your home wifi) except it's more powerful to reach longer distances and is usually best for point to point.
It's very unlikely that they will install actual RF/
microwave equipment as that's considerably more larger, expensive and is not suitable for individual use cases like this. RF in itself is very broad so that's where the confusion lies.
For 1mbps, they're extremely fine as long as line of sight is visible (i.e no obstructions like tree or another building!) - I've tested two point to point devices with a throughput of 45.6mbps over 1.8km (of course local transfer!) so its safe to say they'd be fine.
With that said, I do not recommend taking such an expensive connection - I regret doing that myself, even if you don't see the cost/speed difference, it would make a lot more sense to get additional backup devices like 3G instead of this route. Keep in mind that this connection type comes with its own cons; like you won't be able to cancel their services before the contract ends (the contract is usually for 6 months at a minimum... always make sure to double check and read what you sign!).
Unless you have a very specific requirement to be able to upload at 1mbps then this connection is essentially not value for money - let alone anywhere close to your current Airtel 8mbps connection.
Latency from the device at your location to the device at the next point (i.e the tower you're connected to) would usually be in the 3 to 10ms (usually less as long as you don't max out the throughput) - HOWEVER, please double check if that tower you're getting connected to actually has fiber backbone. The reason why I ask is because the tower I got connected to (the only one in my area from that provider) did not have fiber backbone and hence the service from that tower was carried over via actual RF/microwave line which is not good for latency. It added 25ms to 35ms on top of the 3ms to 10ms. This is all before the connection even reaches your local gateway. It will still be lesser than mobile 3G and closer to your
ADSL line though.
Good luck with what you choose!
P.S, I've since moved on and canceled the connection once the 6 month contract was over.
