Publication

Abstract : In wireless systems, the buffer in the data link layer is not occupied always because of the data traffic. The queue state of the data link layer is unique as indicated by the characteristics of data traffic. The research conducted so far is derived based on the Finite State Markov Chain (FSMC) model that needs more fitting parameters for large complex channels. Furthermore the Adaptive Modulation and Coding (AMC) works well when there is no over flow at the buffer. In case of overflow,AMC has to be designed along with a queuing process to reduce the Packet Dropping Probability (PDP), Packet Error Rate(PER), and to achieve the required throughput. In this paper, a joint frame work of queuing with AMC has been proposed using the dynamic Markov Modulated Poisson Process (dMMPP) model for Quality of Service guaranteed traffic. The performance of proposed queuing model is simulated under the 3G simulation environment comprising Qualnet and MATLAB. Average delay, packet error rate, packet dropping probability and throughput were the metrics used to validate the performance of the dMMPP model. The average delay of packets is reduced by more than 40% in dMMPP when compared with Markov Modulated Poisson Process (MMPP) and Circulant MMPP (CMMPP) without AMC. The minimum packet dropping probability of dMMPP queuing process is around10-8 whereas in MMPP queuing process it is around10-5 with AMC. Furthermore the average delay of the dMMPP queuing process is 20% - 25% less and also yields a better throughput with a difference of more than 0.2 packets/slot, in comparison with MMPP queuing process. The proposed work can also be extended with MIMO Systems with critical traffic issues in future.