Investigation of Efficient Resource Allocation Schemes for WiMAX Networks
نویسندگان
چکیده
WiMax (Worldwide Interoperability for Microwave Access) is a promising wireless technology with the aim of providing the last mile wireless broadband access designed for both fixed and mobile consumers as an alternative solution to the wired DSL and cable access schemes. The purpose of this research project is to investigate efficient resource allocation algorithms for WiMax. To achieve this goal, we investigate efficient PHY layer Partial Usage of SubCarriers (PUSC) allocation as well as MAC layer piggyback bandwidth request mechanisms. At the PHY layer we proposed improvements on the Uplink and Downlink PUSC subcarrier allocation scheme. For the Uplink PUSC we suggested a method by allocating different frequencies to neighbouring cells in combination with the Integer Frequency Reuse (IFR) and Fractional Frequency Reuse (FFR) in order to reduce interferences and collisions. The simulation results exhibit that collision rates can be reduced to zero for both IFR and FFR patterns with the proposed improvement by assuming that perfect power control is used in the system. In addition, there is no collision at cell edges. The results also show that FFR patterns achieve lower inter-cell interference and higher capacities as compared to the IFR patterns. For the Downlink PUSC we introduced an offset scheme with the purpose of increasing the number of users in the system. At the MAC layer we propose an improvement on the piggyback bandwidth request mechanism by increasing the size of the piggyback bandwidth request in order to reduce the number of bandwidth requests and hence improve the resource utilisation. The simulation results demonstrate that our improved scheme achieves higher throughput, less delay and packet loss rates as compared to the standardised piggyback bandwidth request mechanism.
منابع مشابه
A Study on Resource Allocation Algorithms in Wireless Relay Networks
In this paper, the multicast routing problem in wireless relay networks is considered. The resource allocation problem in IEEE 802. 16j WIMAX Networks is discussed. The relay stations are used to improve the transmission quality in WIMAX networks. Most existing approaches try to reduce the energy consumption of a multicast tree. In contrast, the maximization problem to increase the number of re...
متن کاملارزیابی سیاستهای زمانبندی در نسل چهارم شبکههای سلولی (LTE)
New generation of wireless networks, LTE and WiMAX, supports many services which consume a lot of resources (such as VOIP, Video Conference, Digital Video, Multimedia streams and online Multi-player Games). Supporting multi-media services in wireless communication systems provide new resource allocation challenges. Because of high loads in downlink, efficient resource allocation is vital in dow...
متن کاملThe Role of Regulatory in Price Control and Spectrum Allocation to Competing Wireless Access Networks
With the rapid growth of wireless access networks, various providers offer their services using different technologies such as Wi-Fi, Wimax, 3G, 4G and so on. These networks compete for the scarce wireless spectrum. The spectrum is considered to be a scarce resource moderated by the spectrum allocation regulatory (“regulatory” for short) which is the governance body aiming to maximize the socia...
متن کاملModeling and Resource Allocation for HD Videos over WiMAX Broadband Wireless Networks
In order to compare resource allocation schemes for mobile video, it is necessary to have an accurate model of the video traffic that represents real mobile videos. For limited-resource networks like WiMAX, it is essential to maximize the resources utilization. An accurate video model can provide the basis for a reliable traffic predictor that is the core component of any dynamic resource alloc...
متن کامل