CAREER: Delay-Constrained Wireless Networking: Where Shannon Meets Erlang

下一代无线网络的目标是为对延迟敏感的应用提供实时服务。诸如IP语音之类的延迟敏感应用要求无线网络提供服务质量(Qos)保证，例如数据速率、延迟界限和延迟界限违反概率。然而，无线信道的不稳定性使得设计无线网络的服务质量保障机制尤其具有挑战性。在无线网络中，提供侧重于时延约束的服务质量保证的领域通常被称为时延受限的无线网络。该项目关注的是提供统计延迟保证。该问题具有挑战性，因为需要解决延迟限制违规(由排队引起)和比特错误(由信道噪声引起)。为了应对这一挑战，在三个方面进行了研究：1)理论性能限制--开发一种联合编码和排队方法来解决量化物理层误码概率和链路层延迟界限违规的挑战性问题，2)算法设计--开发一个观测器-控制器模型和联合估计/控制方法，以设计明确地提供统计延迟保证的服务质量保证机制，以及3)实验--开发一个基于软件无线电的试验台，在该试验台上实现和评估算法。联合编码和排队方法不仅将在时延受限的无线网络的设计方法中产生重要的原则，同时也促进了信息论和排队论的结合。这项研究将对支持移动电视等对延迟敏感的应用产生重大影响。研究成果将通过会议和期刊传播。

The grail of next-generation wireless networks is providing real-time services for delay-sensitive applications. Delay sensitive applications such as voice-over-IP, require that the wireless networks provide quality of service (QoS) guarantees, e.g., data rate, delay bound, and delay bound violation probability. However, the unreliability of wireless channels makes it particularly challenging to design QoS provisioning mechanisms for wireless networks.In wireless networking, the area of providing QoS assurance with an emphasis on delay constraints is usually called delay constrained wireless networking. This project is concerned about provisioning statistical delay guarantees. The problem is challenging since both delay-bound violation (caused by queueing) and bit errors (due to channel noise) need to be addressed. To address this challenge, research is conducted in three aspects: 1) theoretic performance limits -- developing a joint coding and queueing approach to addressing the challenging issue of quantifying the probability of both physical-layer bit errors and link-layer delay bound violation, 2) algorithm design -- developing an observer-controller model and a joint estimation/control approach to designing QoS provisioning mechanisms that explicitly provide statistical delay guarantees, and 3) experimentation -- developing a software-radio-based testbed, implementing and evaluating the algorithms over the testbed.The joint coding and queueing approach will not only yield important principles in design methodologies for delay-constrained wireless networking, but also advance the union of information theory and queueing theory. The research will have a big impact on supporting delay sensitive applications such as mobile TV. The research findings will be disseminated through conferences and journals.