The Effect of Different Mobile Trajectory on the Performance of VoIP Application in WiMAX Network

WiMAX is a wireless technology based on the IEEE 802.16 standard that provides high speed, throughput, and coverage. Besides QoS, IEEE 802.16 has a data throughput of 100Mbps and a range of 50 kilometers. VoIP “Voice over Internet Protocol” is a versatile and low-cost telephone solution for IP customers. However, many problems remain to be overcome in order to provide a reliable and high-quality audio connection via the Internet. In this paper, the difference in the path of mobile movement through the WiMAX network is studied, as it used types of trajectories (star, square, and Triangle) while making one of the mobiles is fixed without movement and making a comparison between them. A four-cell scenario is presented. One mobile station and one base station are found in each cell. To determine the optimum “VoIP” performance, network performance parameters such as throughput, MOS, jitter, pathloss, and SNR for mobiles 1-1 and 2-1 were used. OPNET 14.5. was used to examine the performance. According to the results, the Throughput and MOS were better when using the Triangle Trajectory, but the result of the jitter was better when using the fixed-mobile compared to the rest of the results and has shown that the inwards trajectory results in improving the efficiency of the network due to the fact that the mobile node gets closer to the base station. Also the value of the pathloss that obtain from mobile1-1(square trajectory) is greater than value obtain by mobile2-1(star trajectory). But the value of SNR in mobile1-1 is less than the value of SNR in mobile2-1