EPCglobal Class-1 Generation-2 (RFID Generation-2) is a wireless communication system in Internet of Things. The models and analyses of RFID Generation-2 are important and have been reported. However, for usefulness and validity, existing models and analyses are mainly based on the assumptions that RFID runs in ideal wireless channels (no packet loss, no error code, and no capture effect). However, there are three co-existing these bad results (packet loss, error code, and capture effect) in the realistic channels, which means that the channels are unreliable. For obtaining comprehensive understanding of RFID Generation-2 performance to conduct relevant important researches, some models are developed for RFID Generation-2 under the unreliable channels. Meanwhile, four feasible methods for calculating the probabilities of those bad results (as models parameters) are given. After validating accuracy of the models through extensive simulation experiments and their fitness for an instance, these models are used to analyze impacts of the parameters on time efficiency, and obtain some key sensitivity factors promoting efficiency. Furthermore, analytical results demonstrate that the analyses considering those co-existing bad results are basis for the researches of some fields such as the general tag identification, the blocked tags identification, the missing tag identification, and the effective hardware design.

EPCglobal Class-1 Generation-2（RFID Generation-2）是物联网中的无线通信系统。RFID Generation-2的模型和分析很重要，并且已有报道。但是，出于有用性和有效性的考虑，现有的模型和分析主要基于以下假设：RFID在理想的无线通道中运行（无数据包丢失，无错误代码和捕获效果）。但是，在实际通道中存在三种不良结果（数据包丢失，错误代码和捕获效果）并存，这意味着通道不可靠。为了获得对第二代RFID性能的全面了解以进行相关的重要研究，在不可靠的渠道下为第二代RFID开发了一些模型。与此同时，给出了四种计算不良结果概率的可行方法（作为模型参数）。通过大量的仿真实验验证了模型的准确性及其适用性后，将这些模型用于分析参数对时间效率的影响，并获得一些促进效率的关键敏感性因素。此外，分析结果表明，考虑那些并存的不良结果的分析是诸如通用标签识别，阻塞标签识别，丢失标签识别以及有效硬件设计等领域研究的基础。这些模型用于分析参数对时间效率的影响，并获得一些促进效率的关键敏感性因素。此外，分析结果表明，考虑那些并存的不良结果的分析是诸如通用标签识别，阻塞标签识别，丢失标签识别以及有效硬件设计等领域研究的基础。这些模型用于分析参数对时间效率的影响，并获得一些促进效率的关键敏感性因素。此外，分析结果表明，考虑那些并存的不良结果的分析是诸如通用标签识别，阻塞标签识别，丢失标签识别以及有效硬件设计等领域研究的基础。