NeTS: Small: A Theoretical Approach to MAC Design for Communication Between Low Cost, Ultra-Low Power Devices

通过在物体上放置标签，物联网正在扩展到日常的物理物体，这些标签具有感知环境的物理属性的能力，并与物体的身份一起传递信息进行处理。目前的惯例是拥有必须与强大的标签读取设备直接通信的无源标签，但这限制了标签向读取器足够普遍的情况下传送信息的能力。另一种更有效的模式是允许标签彼此交换信息，将信息逐个标签地传递，直到到达网关(读取器)设备的范围内的标签。在后一种模式下，物体与网络“断开”连接的可能性将显著降低，使跟踪和监控变得更加无处不在和完整。物体错位将成为过去的问题，特别是在基础设施难以部署的地区，例如在紧急情况和分诊环境中，这些地区往往面临寻找物体或人员或评估条件的重大挑战。这一项目将产生广泛的影响，为用户和整个社会带来重大好处。具体地说，拟议的研究将在促进将物联网领域扩展到日常物品方面对社会产生影响；例如，包括跟踪日常物品，以及促进医疗、建筑和航运等专门领域的物品追踪。教育活动将为学生创造丰富的机会，让他们参与到算法、建模和评估工作中来。这项研究也将有助于教育部分，因为主要调查人员(PI)已经并将继续围绕这一新兴主题设计课程，并将继续让博士生、高中生、本科生和硕士学生参与与这一提议直接相关的研究。PIs从理论角度探索标签到标签通信的基本限制，特别是如何在由这些超低功耗设备构建的网络中最大化通信速率，在这些环境中，他们必须睡眠很长时间(以获取/保存能量)并以不同步的方式运行。从实践的角度来看，将设计和测试能够以接近这些基本限制的速率执行传输的协议。这项研究将创建一个随机优化框架，用于设计和开发实用的分布式协议。本研究中得到的理论算法也将通过实际样机进行测试和实现。

The Internet-of-Things is being extended to everyday physical objects by placing tags on the objects, which have the ability to sense physical attributes of the environment and, along with the object's identity, relay information for processing. The current convention is to have passive tags that must communicate directly with a powerful tag-reading device, but this limits the tags' ability to convey information to scenarios where the readers are sufficiently prevalent. An alternative, more effective paradigm, is to allow the tags to exchange information with one another, passing information tag-to-tag until reaching a tag that is in range with a gateway (reader) device. Under this latter paradigm, the likelihood of objects being "disconnected" from the network will significantly reduce, making tracking and monitoring more ubiquitous and complete. Misplacing objects will become a problem of the past, especially in regions where infrastructure is difficult to deploy, e.g., in emergency and triage settings, which often have the major challenge of finding objects or people or assessing conditions. This project will have broad impact, bringing significant benefits to users and society at large. Specifically, the proposed research will impact society in facilitating the path toward extending the realm of the Internet-of-Things to everyday objects; instances include tracking of everyday objects, as well as facilitating the tracking of objects in specialized domains such as medicine, construction, and shipping. The educational activities will create a rich set of opportunities for students to involve themselves in algorithms, modeling, and evaluation work. The research will also contribute to the educational component as the principal investigators (PIs) have and will continue to design courses around this emerging topic and will continue to involve not only PhD students, but also high school, undergraduate, and masters students in research that directly relates to this proposal.The PIs explore, from a theoretical perspective, the fundamental limits of tag-to-tag communication, in particular how to maximize communication rates in networks built from these ultra-low power devices in environments where they must sleep for large fractions of time (in order to harvest/conserve energy) and operate in an unsynchronized manner. From a practical perspective, protocols will be designed and tested that can perform transmission at rates close to these fundamental limits. The research will create a stochastic optimization framework that is used in design and development of practical distributed protocols. The theoretical algorithms obtained in this research will be also tested and implemented using actual prototypes.