15-02-2013, 09:34 AM
Resource Allocation in OFDMA Wireless Communications Systems Supporting Multimedia Services
Resource Allocation.ppt (Size: 157 KB / Downloads: 16)
INTRODUCTION
We design a resource allocation algorithm for downlink of orthogonal frequency division multiple access (OFDMA) systems supporting real-time (RT) and best-effort (BE) services simultaneously over a time-varying wireless channel .
Existing system
In this project, We take two kinds of QoS requirements into account.
One is the required average transmission rate for both RT and BE services.
The other is the tolerable average absolute deviation of transmission rate (AADTR) just for the RT services, which is used to control
Proposed System
The proposed algorithm aims at maximizing system throughput while satisfying quality of service (QoS) requirements of the RT and BE services.The distinctive feature of the proposed algorithm is the restriction on AADTR, which is introduced to provide stable transmission rates to the RT users.
Expected results
Simulation results show that the proposed algorithm well meets the QoS requirements with the high throughput and outperforms the modified largest weighted delay first (M-LWDF) algorithm that supports similar QoS requirements.
Conclusion
We have formulated the optimization problem, and developed the algorithm that solves it by the dual optimization techniques. It is shown that the proposed algorithm meets well its design goal and outperforms M-LWDF in terms of the packet drop rate of the RT users and the throughput of the BE users.