节点文献
无线低功耗网络中一种基于干扰感知的重传协议的设计与实现
Design and Implementation of a Corruption-Aware Retransmission Protocol for Low-Power Wireless Networks
【作者】 俞杰；
【导师】 董玮；
【作者基本信息】 浙江大学 ， 计算机应用与技术， 2016， 硕士
【摘要】 近年来,无线低功耗技术的发展使得无线传感网的到了广泛的应用。无线传感网络由大量低功耗、资源受限的传感器节点组成,典型的应用方式有环境保护、军事区域监控、桥梁健康度检测等。在无线传感网络中,节点之间的通信是不可靠的。特别是对于像802.15.4一样的低功耗网络,由于干扰、信号衰减、噪声的存在,传输过程中的数据包会发生损坏。本文在商业化的低功耗设备上,探索研究了在干扰存在的情况下,数据包错误发生的特征。进一步地,本文提出了一种基于RSSI的错误检测算法来分辨一个错误包发生错误的严重程度。基于该算法得出的错误程度评估,本文设计了一种动态自适应的编解码方案。该方案基于RS编码,根据错误程度评估选择合适的编码参数来优化网络的性能。本文的主要贡献与创新点如下：1.本文提出了一种能够准确估计数据包中错误比特数的检测算法,该算法基于收包过程中采集到的RSSI序列。2.本文设计了一种基于RS码的自适应编码方案。通过仔细选取相应的编码参数提升了网络性能。该方案在资源有限的低功耗节点上也运行良好。3.本文设计并实现了一个重传协议CARE,并且在商业化的低功耗设备上实施了多项实验。实验结果表明,CARE能够在高干扰的情况下提升网络的性能,同时在完美链路上也不会引入额外的开销。
【Abstract】 With the development of low-power technology, wireless sensor networks are becoming widely used. Wireless sensor network are composed of large number of low-power, resource-limited sensor node. Typical application is enviroment protection, bridge health monitoring, etc. Communications among nodes are unreliable in wireless sensor network,especially for low-power network like 802.15.4 Pakcet corruption happens with interference, fading and noise.In this thesis, we investigate the feature of packet corruption with interference in COTS low-power devices. One step further, we propose a RSSI-based corruption detection algorithm to detect the corruption level of a corrupted packet. Based on this corruption level, we design an adaptive coding scheme. This coding scheme is based on Reed solomon codes(RS code). With careful parameter selection, this scheme is targeted to optimize the network performance.The contributions of this paper are summarized as follows:· We propose a novel corruption detection algorithm considering the transitional region of wireless packet reception, resulting in significantly better accuracy compared with state-of-the-art algorithm on COTS devices.· We design an adaptive coding scheme based on Reed Solomon (RS) codes. We carefully select the coding parameters to optimize the network performance on resource-constrained low-power devices.· We design and implement the CARE retransmission protocol. We conduct extensive ex-periments based on COTS low-power devices. Results show that CARE improves the per-formance significantly for highly interfered links while incurring no additional overhead for good links.