Energy saving scheduling and resource allocation for broadband wireless access networks

• Main Authors: Yen-Yin Chu, 朱衍印
• Other Authors: Yen-Wen Chen
• Format: Others
• Language: en_US
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/79t8c7

博士 === 國立中央大學 === 通訊工程學系 === 105 === The rapid development of high-definition media has stimulated demand for wireless broadband networks and connection-oriented quality for several network services. However, the fourth-generation standard, WiMax (Worldwide Interoperability for Microwave Access) and LTE/LTE-A (Long-Term Evolution /Long-Term Evolution-Advanced) technologies, provide a higher-speed data rate and larger-capacity wireless access networks. Because various mobile applications induce users to access the associated services through handheld devices, energy saving has become one of the most critical concerns in mobile devices, especially for increasing their operation time in practical applications. WiMax and LTE/LTE-A networks provide various sleep mode types and parameters to achieve power-saving, it can be improved by considering more influence factors when BS (Base Station) or eNodeB (evolved Node B) allocated radio resource. However, new radio resource scheduling is still needed to consider either optimal energy utilization or QoS (Quality of Service) satisfaction for both broadband access networks. To achieve this objective, we propose an ESC-US (Energy-Saving Centric Uplink Scheduling) scheme for uplink traffic in WiMax and SDRRS (State Dependent Radio Resource Scheduling) scheme for downlink traffic in LTE. The ESC-US scheme provides rtPS (real-time Polling Services) and nrtPS (non-real-time Polling Services) scheduling algorithms that apply the “just enough QoS” and “sleep before transmission” concepts to achieve energy-saving centric objective. The simulation results demonstrate that both schemes satisfy the desired QoS and achieve better energy consumption compared to the conventional scheme. The SDRRS scheme involves the burst-scheduling concept with respect to transitions between the active and the sleep states to adjust the inactivity timer. The performance was investigated via exhaustive simulations indicated that the SDRRS scheme can reduce energy consumption more effectively compared with the other schemes. In LTE-A network, the UE (User Equipment) with LTE-A capability could aggregate more than one CC (Component Carriers) for more channel bandwidth. However, the LTE-A UE can be allocated RBs (Resource Block) in different CCs, but LTE UE can only be allocated RBs in the same CC. To address this issue, we propose a novel scheme that considers the localized subcarrier by properly using the Gale-Sharply concept to schedule the uplink traffic of both LTE and LTE-A UE in LTE-A network environment. Additional research is presented on machine-to-machine communication, which studies an uplink scheduling scheme to minimize signaling overhead and maximize system throughput in LTE network. A crucial problem in the machine-to-machine communication is to reduce signaling overheads between a large number of connected devices and eNodeB. We propose scheme dynamically adjusts group members that considers not only QoS and channel condition but also applies the allocation-before-request concept to allocate the residual bandwidth.