Multi-user Scheduling Schemes for Simultaneous Wireless Information and Power Transfer

In this paper, we study the downlink multi-user scheduling problem for a time-slotted system with simultaneous wireless information and power transfer. In particular, in each time slot, a single user is scheduled to receive information, while the remaining users opportunistically harvest the ambient radio frequency (RF) energy. We devise novel scheduling schemes in which the tradeoff between the users' ergodic capacities and their average amount of harvested energy can be controlled. To this end, we modify two fair scheduling schemes used in information-only transfer systems. First, proportionally fair maximum normalized signal-to-noise ratio (N-SNR) scheduling is modified by scheduling the user having the jth ascendingly ordered (rather than the maximum) N-SNR. We refer to this scheme as order-based N-SNR scheduling. Second, conventional equal-throughput (ET) fair scheduling is modified by scheduling the user having the minimum moving average throughput among the set of users whose N-SNR orders fall into a certain set of allowed orders Sa (rather than the set of all users). We refer to this scheme as order-based ET scheduling. The feasibility conditions required for the users to achieve ET with this scheme are also derived. We show that the smaller the selection order j for the order-based N-SNR scheme, and the lower the orders in Sa for the order-based ET scheme, the higher the average amount of energy harvested by the users at the expense of a reduction in their ergodic capacities. We analyze the performance of the considered scheduling schemes for independent and non-identically distributed (i.n.d.) Ricean fading channels, and provide closed-form results for the special case of i.n.d. Rayleigh fading.Comment: 6 pages, 3 figures. Submitted for possible conference publicatio

Group scheduling in cellular networks

Title from PDF of title page, viewed on March 12, 2013Thesis advisor: Cory BeardVitaIncludes bibliographic references (p. 45-47)Thesis (M.S.)--School of Computing and Engineering. University of Missouri--Kansas City, 2012With the ever increasing number of users and the usage of data in cellular networks, meeting the expectations is a very difficult challenge. To add to the difficulties, the available resources are very limited, so proper management of these resources is very much needed. Scheduling is a key component and having a scheduling scheme which can meet the Qos requirements such as Throughput, Fairness and Delay is important. A new dimension to scheduling known as Group Scheduling has been designed in this project. Common scheduling schemes, which include Maximum Carrier to Interference, Round Robin, Proportional Fair and Modified Largest Weighted Delay First, have been studied and analyzed. In a network where the users are divided into a number of groups, such as Public Safety which has Fire, Health and Police, the Group Scheduling scheme is designed to find the right balance between Throughput and Fairness. It allocates the resources to the best available group and the best available user inside that particular group based on a contention mechanism which takes into account the location of the user and the fast varying channel conditions for that user. The Proportional Fair scheme has been used as the basis for this Group Scheduling scheme and results have been simulated to show that it performs better than the other scheduling schemes studied for this project. Also, the scheme has been shown to be highly reliable.Introduction -- Background -- Code implementation -- Results and analysi