Networking & Control Issues for Mobile Radio Communication Systems

9415530 Rappaport在大范围内为众多移动平台提供可靠的交换通信的问题是当前世界范围内具有重大障碍的主要技术挑战。网络消息可以是语音、数据和流通信的混合，并且移动平台可能具有各种通信需求和移动性特征。由于有限的通信资源基本上无处不在地为大量人口提供服务，因此迫切需要创建合适的网络概念以及分析模型和方法，这些模型和方法允许对系统性能进行理论预测，检查参数权衡，以及对相关问题的内聚视图。潜在系统和方案的物理复杂性有时使分析的可追溯性难以捉摸，并限制了通常从此类模型中获得的观点和洞察力。研究的目的是设计适合移动通信的新技术和方案，并开发易于处理的性能分析和比较模型。计算机模拟将被用作验证和支持工具。从网络的角度来看，特别令人感兴趣的是提供智能特征的技术，它们使移动网络能够通过调整和适应通信环境的变化来保持性能水平。针对蜂窝和非蜂窝配置，将研究考虑流量负载、干扰和拓扑结构的通信资源的动态控制、分配和管理。需要调查的一般领域包括：管理通信平台移交的技术；利用空间宏观多样性特征；以及通信资产的动态控制和分配——包括通道和网关的借用和共享。实现这一目标的程序可能包括中央控制和分布式控制的混合。具体主题有：带切换的蜂窝通信系统的总体流量类型性能；具有混合呼叫和平台类型的蜂窝系统；分层叠加的细胞结构；渠道与门户结合借用；自主信道分配方案。将考虑这些技术在各种接入技术中的适当性。该研究将强调创建可分析的可处理模型。这种方法有助于建立一个基础，提供基本的见解，并促进特定类型的新技术和改进技术的发明。预计这项调查的结果将设计出新的技术，以便在广泛的地理区域内改进与大量移动平台的通信。此外，分析模型和方法将为理解和设计移动通信网络提供增强的基础。*** ***************************************************************** ************ Aubrey M. Bush项目主任，网络和通信研究和基础设施国家科学基金会4201 Wilson Boulevard Arlington， VA 22230 703 306 1949 abush@nsf.gov

9415530 Rappaport The problem of providing numerous mobile platforms with reliable switched communications over large areas is a major current world-wide technological challenge with significant hurdles. Network messages can be a mixture of voice, data, and stream traffic, and the mobile platforms may have various communications needs and mobility characteristics. With limited communication resources to service large populations essentially everywhere, the need to create suitable networking concepts along with analytical models and methodology that permit theoretical prediction of system performance, examination of parameter trade-offs, and cohesive views of relevant issues is acute. The physical complexity of potential systems and schemes sometimes makes analytical tractability elusive and limits the perspective and insight that is often gained from such models. The objective of the research is to devise new techniques and schemes that are suitable for mobile communications and to develop tractable models for performance analysis and comparisons. Computer simulation will be used as a validation and supporting tool. Of particular interest, from the viewpoint of networking, are techniques that provide intelligent features in the sense that they enable mobile networks to maintain performance levels by adjusting and adapting to changes in the communications environment. Dynamic control, assignment, and management of communications resources in consideration of traffic loading, interference, and topology will be investigated for cellular and non-cellular configurations. General areas to be investigated include: techniques for managing hand-offs of communicating platforms; use of spatial macro-diversity features; and dynamic control and assignment of communications assets - including both borrowing and sharing of channels and gateways. Procedures to accomplish this may involve mixtures of central and distributed control. Specific topics are: overall traffic pe rformance for cellular communication systems with hand-off; cellular systems with mixed call and platform types; hierarchically overlaid cellular architectures; combined channel and gateway borrowing; and autonomous channel assignment schemes. Appropriateness of the techniques in various access technologies will be considered. The research will emphasize the creation of analytically tractable models. This approach helps to establish a foundation that provides fundamental insights and fosters the invention of new and improved techniques of a particular genre. It is expected that as a result of this investigation, new techniques will be devised that will allow improved communications with large numbers of mobile platforms over wide geographical areas. In addition, the analytical models and approach will provide an enhanced foundation for understanding and designing mobile communications networks. *** ***************************************************************** ************ Aubrey M. Bush Program Director, Acting Deputy Divison Director Division of Networking and Communications Research and Infrastructure National Science Foundation 4201 Wilson Boulevard Arlington, VA 22230 703 306 1949 abush@nsf.gov