Power saving in multiuser adaptive modulation transmission

A transmitter power saving mechanism is presented in this paper where an Adaptive Modulation (AM) strategy is performed by the system. The power saving is accomplished by fixing a predefined Quality of Service (QoS) indicator in the system through the demanded application Symbol Error Rate (SER). The obtained results are encouraging as they show a great decrease in the system power budget. The multiuser system capability is also exploited to achieve larger power saving values, by scheduling the user with the best channel characteristics at each time instant. The system saved power is then presented through a closed form expression and compared its results to computer simulations where a very tight performance is obtained.