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As low-power wide-area network (LPWAN) end devices (EDs) are deployed in massive scale, their economic and environmental costs of operation are becoming too significant to ignore and too difficult to estimate. While LPWAN architectures and protocols are designed to primarily save energy, this study shows that energy saving does not necessarily lead to lower cost or environmental footprint of the network. Accordingly, a theoretical framework is proposed to estimate the operational expenditure (OpEx) and environmental footprint of LPWAN EDs. An extended constrained optimization model is provided for the ED link assignment to gateways (GWs) based on heterogeneous ED configurations and hardware specifications. Based on the models, a simulation framework is developed which demonstrates that OpEx, energy consumption, and environmental footprint can be in conflict with each other as constrained optimization objectives. We demonstrate different ways to achieve compromises in each dimension for overall improved network performance. 相似文献
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Sercan Yalçın 《International Journal of Communication Systems》2023,36(5):e5433
The artificial intelligence-based spectrum sensing approach is extremely important in terms of effective bandwidth utilization for low power wide area networks (LPWANs) based on cognitive radio networks (CRNs). Most studies perform spectrum detection with CRNs using optimization or deep neural network methods. However, optimization-based spectrum detection approaches based on current LPWANs are scarce. For this purpose, in this study, a hybrid optimization methodology integrated with CRNs is proposed for LoRa, which is one of the most compatible LPWAN technologies in the Internet of Things (IoTs) recently. In the particle swarm optimization (PSO) part of this hybrid methodology, agent users are created so that secondary users (SUs) could use the licensed band of primary users (PUs) in cognitive radio. On the genetic algorithm side, LoRa error rates are minimized in order to further improve the performance of the proposed method. In this way, effective spectrum sensing is performed in the LoRa network. Various LoRa-CRN experiments have been carried out in the simulation environment, and the probability of detection and false alarm performances have been compared with both theoretical and proposed approaches in terms of quality estimation parameters. It is clear from the results that the proposed methods give successful results for the LoRa-CRNs. 相似文献
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高比例的可再生能源接入、电力市场化改革和"互联网+"智慧能源的快速发展需要大量的数据支撑,并实现物理、商业、信息的广泛互联、智能互动。关键步骤之一是建立泛在电力物联网(Ubiquitous Power Internet of Things,UPIoT),实现电力系统中人与物、物与物、人与人之间随时随地通信。首先介绍了UPIoT的发展背景与基本概念、主要的低功耗广域网络(Low Power Wide Area Network, LPWAN)技术,然后以LoRa物联网解决方案为例介绍了基于LPWAN的UPIoT的体系架构及性能。最后探讨了UPIoT的应用前景,并指出了UPIoT需重点研究和解决的两个特殊问题,即:低压电力线载波通信(PLC)和强电磁干扰环境下的信号处理。 相似文献
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LoRa是目前工业界大力推广的一种低功耗广域网技术(LPWAN)技术,但其中的核心调制技术专利由美国Semtech公司拥有,其技术细节没有被公开。基于此,针对LoRa的调制解调技术原理进行详细的数学描述,并给出了具体的调制解调算法。同时,对LoRa调制的性能进行了高斯白噪声信道及多径衰落信道下的仿真比较,仿真结果验证了LoRa调制技术在低速远距离通信场景中的优越性。 相似文献
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Mohammad Al Mojamed 《计算机系统科学与工程》2022,40(1):259-273
The Long-Range Wide Area Network (LoRaWAN) is one of the used communication systems that serve and enables the deployment of the Internet of Things (IoT), which occasionally transmit small size data. As part of the Low Power Wide Area Network (LPWAN), LoRaWAN is characterized by its ability for low power consumption. In addition, it is built to provide more extended coverage and higher capacity with minimum cost. In this paper, we investigate the feasibility and scalability of LoRaWAN for the Mina area using a realistic network model. Mina, known as the world’s largest tent city, is a valley located in the east of Makkah city and surrounded by mountains. It accommodates up to 3 million pilgrims annually and contains more than 100000 tents. The performance was evaluated based on a fire detection-like application. Extensive simulations were conducted using the OMNeT++ simulator and Flora model to determine the delivery ratio, collision, and SF distribution for the simulated scenario with a network consisting of up to ten thousand end devices. The conducted simulations show a promising result for LoRaWAN technology for Mina city. It showed a consistent performance for LoRaWAN in most simulated scenarios when a high success ratio was achieved. 相似文献
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本文介绍了NB-IoT与LoRa等低功率广域网络技术在已经实施的项目中出现终端功耗过高、接入容量过低、网络可靠性不足等方面的问题。并提出了融合mMIMO和长距离窄带传输,以免许可mMIMO随机接入(mGFRA)技术为核心的TurMass技术及其在提升接入容量的特点。基于TurMass技术SoC芯片的模块化设计整合了射频电路与数字基带SoC,所设计的射频芯片通过55nm RFCMOS工艺进行流片验证。点对点测试与系统测试结果表明,芯片发射端的信道发射功率21.5dBm,减去接收灵敏度-140.7dBm的链路预算为162.2dBm,表示可以容忍的最大路径损耗,具有无线网络覆盖较远的特点,并且完成测试确认没有丢包的情况发生。 相似文献