A Probabilistic Transmission Slot Selection Scheme for MC-CDMA Systems Using QoS History and Delay Bound

In this paper, we propose an efficient transmission slot selection scheme for Band Division Multi-Carrier-CDMA (BD-MC-CDMA) systems under the constraints of packet loss and delay bound for each individual session. By utilizing channel dynamics together with the delay deadline and loss history, one can determine whether to transmit or not on each time slot, based on the prediction of future channel variations. In this way, one can enhance the chance for transmitting packets with the best channel quality. To validate the efficiency of the proposed algorithm, we model each sub-band as a discrete time Markov Chain using a finite state Markov channel (FSMC) and derive the criteria required for transmission decision. Simulation results show that our proposed scheme can satisfy quality of service (QoS) requirements for real-time traffic with a minimum use of power, while increasing throughput of non-real-time traffic with the power saved from real-time traffic.