What can be the reasons of a Call drop?

Answer 1

1. If the network is congested and u are low priority user then ur call might be dropped.2. The signal level for an ideal call isTransmit +43db

Receive -60 ~ -80db

Some times while receiving call, suppose due to pathloss or shadowing, if ur receiving signal level is -95db, then ur call will be dropeed.

During the site survey, Site selection is very much important to avoid the effect of path loss and shadowing.

3. Sometimes there are pockets due to inappropiate radio network planning, in those pockets ur call might be dropped.

Appropiate Radio Planning and the adjustment of Antenna's Down Tilt is very much important to resolve this problem.4. During hanover, if the interferrence from the neighbouring BTS is too high the call might be droped.

Appropiate Radio Planning and the adjustment of Antenna's Down Tilt is very much important to resolve this problem5. Somtimes SACCH, FACCH signalling channels are not available to provide u a TCH channel. In that case call might be dropped. Repeated SACCH, FACCH can solve this problem.6. Some times it might happen that you are too far from the center of BTS, that is you are at the cell boundary. At that u might face problem to make a call as the transmitted signal from ur MS will not reach BTS.

High gain antenna's can solve this problem. there are other different techniques to resolve this problem. But all these solutions varies from vendor to vendor