Recently, tag-to-tag (T2T) backscattering technique in a passive RFID system has received broad attention due to its superiority for large-scale network applications. If used to implement a Network of Tags, use of T2T communication allows inherent communication parallelism, thus supporting orders of magnitude larger capacity than centralized RFID reader-based systems. To unleash the potential of T2T communication, turbo backscattering operation enables the implementation of a multi-hop network of tags, which supports larger network coverage of a Network of Tags. However, due to asymmetric communication links and interferences among tags’ transmissions in such a T2T backscattering based network, the routing protocol design has become one of the main technical challenges, especially for large-scale networks. Furthermore, the computation time of T2T routing protocols increases exponentially with the number of tags, greatly limiting the practicability of such large-scale backscattering networks. In this paper, we present the design of a Network of Tags model to address these challenges, and we propose novel routing protocols for three distinct types of tags with different hardware capabilities. To address the issue of computational processing time of the routing protocol for large-scale T2T networks, we propose a new scheme with linear time complexity. We evaluate and compare the performance of the proposed protocols, as well as investigate the impact of network parameters on the performance.

中文翻译：

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大规模无源标签网络的多跳标签间路由协议设计

近来，无源RFID系统中的标签到标签（T2T）反向散射技术由于其在大规模网络应用中的优越性而受到广泛关注。如果用于实现标签网络，则T2T通信的使用可实现固有的通信并行性，因此与基于集中式RFID读取器的系统相比，可支持更大数量级的容量。为了释放T2T通信的潜力，Turbo反向散射操作可实现标签的多跳网络，该网络支持标签网络的更大网络覆盖范围。然而，由于在这样的基于T2T反向散射的网络中不对称的通信链路和标签传输之间的干扰，路由协议设计已成为主要技术挑战之一，特别是对于大规模网络。此外，T2T路由协议的计算时间随着标签数量的增加而成倍增加，极大地限制了这种大规模反向散射网络的实用性。在本文中，我们介绍了标签网络模型来解决这些挑战，我们针对具有不同硬件功能的三种不同类型的标签提出了新颖的路由协议。为了解决大规模T2T网络路由协议的计算处理时间问题，我们提出了一种具有线性时间复杂度的新方案。我们评估并比较了所提出协议的性能，并研究了网络参数对性能的影响。