Advantages of TDMA Operation

An often quoted advantage of TDMA operation is the ease with which users can be given variable data rate services by simply assigning them multiple time slots. For example, a GSM user could be given all eight time slots within a frame, giving a total fully coded user data rate of 8 x 9600 bps = 76800 bps. (This assumes that the users' equipment has sufficient processing power to process all eight time slots simultaneously.) This facility has its dual in assigning multiple frequency slots in an FDMA system, however, this is perceived to require more complex hardware for implementation.
A second advantage of TDMA is the commonality in the base-station of the transmitting hardware for all time slot users. There is only one power amplifier required to support multiple users (albeit with a wider modulation bandwidth). Traditionally with FDMA, each user channel at the base-station has required an individual power amplifier, the output of which is combined at high power to feed a single common antenna. The advent of multi-carrier linear power amplifiers in the last few years has begun to alter this TDMA/FDMA bias.

For packet-based applications, TDM/TDMA operation is clearly a well-matched access method.