One of the more challenging aspects of TDM/TDMA operation is the establishment of system timing in order to ensure correct time slot arrival and framing and to cope with variable path delays in the wireless systems. While these can be accommodated by careful design, for small multi-user communication systems, the overhead of system timing may favour the use of FDMA methods. | ![]() |
TDMA use also requires each user terminal to support a much higher data rate than the user information rate. This implies faster processing for modulation and demodulation, wider bandwidth in the TX/RX section and in particular requires a higher peak power rating for the power amplifier in a wireless application compared with an FDMA solution. (Assuming equal symbol average energy for both systems to achieve equivalent range, the symbol duration for the TDMA system must be much shorter than the FDMA equivalent and hence the transmitted symbol power for TDMA must be correspondingly higher than for FDMA. Note: the average symbol power and hence average battery drain for both systems are identical.) |