Abstract:
Worldwide Interoperability for Microwave Access (WiMAX) is based on the IEEE 802.16
Standard with mobility support from the 802.16e amendment and it enables convergence of mobile and fixed broadband wireless networks covering metropolitan and rural areas.WiMAX networks were expected to be the main Broadband Wireless Access (BWA) technology that provided several services such as data, voice, and video services (real and non-real services) including different Quality of Services (QoS) classes, which in turn were defined by IEEE 802.16 standard. The IEEE 802.16 standard doesnot specify scheduling mechanisms and so far many solutions are proposed in the science world. Scheduling in WiMAX became one of the most challenging issues, since it was responsible for distributing available resources of the
network among all users; this led to the demand for constructing and designing highly
efficient scheduling algorithms in order to improve the network utilization, increase the
network throughput, and minimize the end-to-end delay.In this research, we presented a
simulation study to measure the performance of two scheduling algorithms in WiMAX, which were Packet Scheduling Scheme (PSS)for Multiple Services in Mobile WiMAX System proposed by Lee and Park and Channel-Aware Scheduling Algorithm for Mobile WiMAX network(CASA)proposed by El-Shennawy etal.Simulation results are obtained using Simulink and performance of these two scheduling schemes in terms of throughput, delay, jitter, packet losses and time complexitywere evaluated.PSS exhibits a good performance in term of throughput and average packet loss. The throughput was higher and the average packet loss was lower. CASA exhibits a lower average delay and lower average jitter.
Computational time of PSS was higher than CASA.In a reliable communication such as data and voice, throughput and packet delivery are very important, thereforePSS is more
appropriate. In unreliable communication in terms of video or video communication, where delay and jitter are very important, CASA is more appropriate.
