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Opportunistic transmission scheduling for next generation wireless communication systems with multimedia services.

机译：具有多媒体服务的下一代无线通信系统的机会传输调度。

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摘要

The explosive growth of the Internet and the continued dramatic increase for all wireless services are fueling the demand for increased capacity, data rates, and support of different quality of service (QoS) requirements for different classes of services. Since in the current and future wireless communication infrastructures, the performances of the various services are strongly correlated, as the resources are shared among them, dynamic resource allocation methods should be employed. With the demand for high data rate and support of multiple QoS, the transmission scheduling plays a key role in the efficient resource allocation process in wireless systems. The fundamental problem of scheduling the users' transmissions and allocating the available resources in a realistic CDMA wireless system that supports multi-rate multimedia services, with efficiency and fairness, is investigated and analyzed in this dissertation.;Our proposed approach adopts the use of dynamically assigned data rates that match the channel capacity in order to improve the system throughput and overcome the problems associated with the location-dependent and time-dependent errors and channel conditions, the variable system capacity and the transmission power limitation. We first introduce and describe two new scheduling algorithms, namely the Channel Adaptive Rate Scheduling (CARS) and Fair Channel Adaptive Rate Scheduling (FCARS). CARS exploits the channel variations to reach high throughput, by adjusting the transmission rates according to the varying channel conditions and by performing an iterative procedure to determine the power index that a user can accept by its current channel condition and transmission power. Based on the assignment of CARS and to overcome potential unfair service allocation, FCARS implements a compensation algorithm, in which the lagging users can receive compensation service when the corresponding channel conditions improve, in order to achieve asymptotic throughput fairness, while still maintaining all the constraints imposed by the system.;Furthermore the problem of opportunistic fair scheduling in the uplink transmission of CDMA systems, with the objective of maximizing the uplink system throughput, while satisfying the users' QoS requirements and maintaining the long-term fairness among the various users despite their different varying channel conditions, is rigorously formulated, and a throughput optimal fair scheduling policy is obtained. The corresponding problem is expressed as a weighted throughput maximization problem, under certain power and QoS constraints, where the weights are the control parameters that reflect the fairness constraints. With the introduction of the power index capacity it is shown that this optimization problem can be converted into a binary knapsack problem, where all the corresponding constraints are replaced by the users' power index capacities at some certain system power index. It is then argued that the optimal solution can be obtained as a global search within a certain range, while a stochastic approximation method is presented in order to effectively identify the required control parameters. Finally, since some real-time services may demand certain amount of service within specific short span of time in order to avoid service delays, the problem of designing policies that can achieve high throughput while at the same time maintain short term fairness, is also considered and investigated. To this end a new Credit-based Short-term Fairness Scheduling (CSFS) algorithm, which achieves to provide short-term fairness to the delay-sensitive users while still schedules opportunistically the non-delay-sensitive users to obtain high system throughput, is proposed and evaluated.
机译：互联网的爆炸性增长以及所有无线服务的持续急剧增长，正推动着对容量，数据速率的增长以及对不同服务类别支持不同服务质量（QoS）需求的需求。由于在当前和将来的无线通信基础结构中，各种服务的性能紧密相关，因为它们之间共享资源，因此应采用动态资源分配方法。随着对高数据速率的需求以及对多种QoS的支持，传输调度在无线系统中有效的资源分配过程中起着关键作用。本文研究和分析了一个现实的，支持多速率多媒体服务的高效，公平的CDMA无线系统中调度用户传输和分配可用资源的基本问题。分配与信道容量相匹配的数据速率，以提高系统吞吐量并克服与位置和时间相关的误差和信道状况，可变的系统容量和发射功率限制相关的问题。我们首先介绍并描述两种新的调度算法，即信道自适应速率调度（CARS）和公平信道自适应速率调度（FCARS）。 CARS通过根据变化的信道条件调整传输速率并执行迭代过程来确定用户可以通过其当前信道条件和传输功率接受的功率指标​​，从而利用信道变化来达到高吞吐量。基于CARS的分配并克服潜在的不公平服务分配，FCARS实现了一种补偿算法，其中滞后的用户可以在相应的信道条件改善时接收补偿服务，以实现渐近吞吐量的公平性，同时仍然保持所有约束此外，CDMA系统的上行传输中的机会公平调度问题，目的是最大化上行系统吞吐量，同时满足用户的QoS要求并保持各个用户之间的长期公平性。严格制定了它们各自不同的信道条件，并获得了吞吐量最优的公平调度策略。在某些功率和QoS约束下，相应的问题表示为加权吞吐量最大化问题，其中权重是反映公平性约束的控制参数。通过引入功率指标容量，可以看出该优化问题可以转换为二元背包问题，其中所有相应约束都由某些系统功率指标下的用户功率指标容量代替。然后有人认为，最优解可以在一定范围内作为全局搜索获得，同时提出了一种随机逼近方法，以有效地识别所需的控制参数。最后，由于某些实时服务可能会在特定的短时间内要求一定数量的服务，以避免服务延迟，因此，在设计策略时可以实现高吞吐量同时保持短期公平性的问题也被考虑在内。并进行调查。为此，一种新的基于信用的短期公平性调度（CSFS）算法是：为延迟敏感的用户提供短期公平性，同时仍然机会性地调度非延迟敏感的用户以获得高系统吞吐量。提出并评估。

著录项

  • 作者

    Li, Chengzhou.;

  • 作者单位

    New Jersey Institute of Technology.;

  • 授予单位 New Jersey Institute of Technology.;
  • 学科 Engineering Electronics and Electrical.
  • 学位 Ph.D.
  • 年度 2005
  • 页码 95 p.
  • 总页数 95
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类 无线电电子学、电信技术;
  • 关键词

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