Mobile Station:

A station in the cellular radio system intended to use while in motion at unspecified locations is called a mobile station. Mobile stations may be hand-held personal units (portables) or installed in vehicles (mobiles)

Forward Channel:

It is a radio channel used for transmission of information from the base station to the mobile.

Base station controller:

The Base Station Controller manages the radio resources for one or more BTSs. It handles radio-channel setup, frequency hopping, and handovers, as described below. The BSC is the connection between the mobile station and the Mobile service Switching Center (MSC).

Mobile Switching Center (MSC):

An MSC also called a Mobile Telephone Switching Office (MTSO) is a switching center which coordinates the routing of calls in a large service area. In a cellular radio system, the MSC connects the cellular base stations and the mobiles to the PSTN (Public Switched Telephone Network, PSTN, is a global telecommunications network which connects conventional landline telephone switching centers, called central offices, with MSCs throughout the world).

Roaming:

A mobile station which operates in a service area (market) other than that from which service has been subscribed is called a roaming.

Transceiver:

A device capable of simultaneously transmitting & receiving radio signals.