FDMA, TDMA and CDMA

TDMA-time division multiple access:

The time division multiple access refers to dividing a broadband radio channel into several timeslot, so that every subscriber seizes one of the timeslots; and the signal is received (or transmitted) only in that specific timeslot. That is the reason why it is called time division multiple access. This multiple access mode is used in digital cell systems and GSM as well.

CDMA-Code division multiple access:

It is a multiple access mode in which the spread spectrum technique is used to form different code sequences. It is quite different from FDMA and TDMA. In FDMA and TDMA, the subscriber information is divided or separated based on the frequency and time, but CDMA mode can transmit information of multiple subscribers via the same radio channel at the same time.