Long Term Evolution (LTE) constitutes a significant milestone in the evolution of 3G systems towards fourth generation (4G) technologies. The performance targets promised by LTE makes it an ideal solution to accommodate the ever increasing demand for wireless broadband. LTE's promised performance targets were made possible due to improvements such as a simplified system access architecture and a fully IP-based platform. LTE has also great enhancements in its enabling radio technologies by introducing Orthogonal Frequency Division Multiplexing (OFDM) and advanced antenna technologies. In addition, LTE capabilities are further improved with enhanced Quality of Service (QoS) support for multiple data services, such as voice and other multimedia applications. LTE packet scheduling plays an essential role as part of LTE's Radio Resource Management (RRM) to enhance the system's data rate and to support the diverse QoS requirements of mobile services. LTE packet scheduler should intelligently allocate radio resources to mobile User Equipments (UEs) such that the LTE network adheres to its performance requirements. In our work, we perform a performance evaluation of multiple LTE scheduling algorithms proposed for LTE uplink transmission. The evaluation takes place in single and mixed traffic scenarios to exploit the strengths and weaknesses of proposed algorithms. Simulation results illustrated the importance of a scheduler's awareness of uplink channel conditions and QoS requirements in the presence of single and multiple traffic scenarios. Accordingly, we provide recommendations for future scheduling algorithm proposals, and ways to enhance the existing schedulers. / Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2011-05-07 12:43:54.983

<p> Wireless metropolitan area networking based on IEEE 802.16 is expected to be widely used for creating wide-area wireless backhaul networks, where each subscriber station (SS) is responsible for forwarding traffic for a number of connections. Quality of Service (QoS) provisioning is an important aspect in such networks. The IEEE 802.16 standard specifies that the bandwidth requests sent by the SS are for individual connections and pass only the number of bytes requested from each connection. This is inefficient for backhaul networks where each SS may be responsible for forwarding packets for a relatively large number of connections and the bandwidth request messages consume much bandwidth unnecessarily. Furthermore, the standard does not include latency information, which makes it difficult for the base station (BS) to schedule real-time traffic. </p> <p> In this thesis we study real-time voice traffic support in IEEE 802.16-based backhaul networks. We propose a simple enhancement to the bandwidth request mechanism in 802.16 for supporting packet voice traffic. First, the SS combines the bandwidth requests of multiple voice connections, which are associated to it and have the same traffic parameters, and aggregates the bandwidth requests to the BS. This makes the bandwidth request process more efficient by saving transmission time of both the BS and the SSs. Second, in order to facilitate the BS to make resource allocation decisions, the aggregate bandwidth requests include information about the latency requirements of buffered real-time packets at the SSs. We propose three different bandwidth request and packet scheduling schemes, each of which requires a different amount of information in the bandwidth requests. Our results show that the proposed bandwidth request and scheduling schemes achieve significantly lower packet loss probability than standard 802.16 bandwidth requests and weighted round robin. The results further show that there is an optimum point about how much delay information the SS should report to the BS in order to best utilize the uplink resources while providing satisfactory real-time performance for the voice traffic. </p> / Thesis / Master of Applied Science (MASc)