A Cumulated Jitter-based Rate Control Mechanism For Wireless Multimedia Transmission

With the rapid development of broadband wireless networks, the use of wireless multimediaapplications has become more and more widely. And obviously the achievement of the applicationsneeds the support of the key technologies, for example, video streaming in wireless networktransmission technology, especially the assurance of the quality of service (QoS), which is one ofthe most important influencing factors of the technology in wireless video performance. In order toimprove the performance of wireless multimedia transmission, a lot of researches have been made,while the rate and network congestion control is one of the most important directions.In this thesis, the author first studies the transmission characteristics of the radio channel, aswell as several widely used end-to-end packet loss distinction methods in today’s wireless networkapplications. And based on this foundation, proposes a new rate control method CJ-SIMD, whichuses the accumulated jitter as a control criterion to distinguish lost packets. The cumulative jitterscheme is reinforced with a delay factor that measures on a per round basis the buffer occupancy atthe bottleneck path between the sender and the receiver.This is done to reduce the risk ofunnecessary decrease of the transmission rate every time that incipient congestion is reportedthrough the cumulative jitter scheme. Based on this, with SIMD rate control algorithm, the newmethod can alleviate network congestion and improve the utilization of network resources.On the NS-2simulation platform, the algorithm CJ-SIMD is compared with AVTC, Spike,ZigZag algorithms. Simulation results show that, CJ-SIMD algorithms is more accurate todistinguish the cause of the loss of the data packet, to control the transmission rate according to thedifferent type of lost data packet and to alleviate network congestion, thus improving the utilizationof network resources. Compared to AVTC, Spike, ZigZag algorithms, CJ-SIMD algorithmperforms better with higher throughput and lower congestion packet loss rate.