基于LoRa无线扩频通信的水情监测与预警系统

为解决目前水情监测系统中存在通信距离受限、功耗大、成本高、无法泛组网的问题,提出了一种基于LoRa（Long Range）扩频技术的水情监测与预警系统。通过采用新型的LoRa无线扩频技术,使用无线传感器网络自适应占空比协议优化网络性能与功耗,并结合当前流行的微控芯片、传感器与阿里云物联网（Internet of Things,IoT）平台,构建了一套覆盖范围广、低功耗、低成本、组网灵活简单、能远距离通信、抗干扰能力强的水情远程监测与预警系统。系统设计完成后,在长江水域重庆段对系统进行了测试,验证了系统设计的可行性、组网通信的有效性以及远距离传输数据的特性,为水文水情数据的自动化远程监测提供了一种新的技术方案。     

无线LoRa在全业务泛在电力物联网终端层的应用

国家电网公司提出的“全业务泛在电力物联网”是能源网和物联网的融合演进,是服务于广大用户的关键能源基础设施。随着电力物联网的战略兴起,输电线路在线监测采集节点和监测规模将骤增,采用何种技术体制建设现场通信网络,兼顾考虑长距离、低功耗、高可靠等多重因素至关重要。对无线LoRa技术特点及优势进行了研究,结合输电线路在线监测的应用场景及需求,提出基于无线LoRa的输电线路在线监测组网方案并对其进行了适应性分析,研究成果在该领域具有一定参考意义。     

水产养殖物联网监控系统的设计

针对蓝色经济区水产养殖粗放式管理现状,设计了新型水产养殖物联网监控系统。该系统的传感器节点负责水质数据采集功能,并通过Zigbee无线传感器网络将数据发送给汇聚节点,汇聚节点通过GPRS模块接入Internet网络,将数据传送至远程监控中心。同时监控中心设置的各项参数通过Internet和汇聚节点传到采用PIC单片机的控制节点,实现水质的自动控制。监测中心软件采用C＋＋ Builder开发,为用户提供形象直观的实时数据监测平台。经过在日照市某水产养殖基地的试用,系统性能满足水产养殖水质监控的应用要求。     

基于LoRa技术的中波台站物联网监控系统设计

本文基于现在发展迅猛的LoRa及物联网技术,提出了一种基于LoRa协议的智能中波台站物联网监控系统设计方案。该方案以LoRa网络实现系统感知层设计,基于简单的星型组网架构,构建低功耗广域网智能中波台站物联网监控系统,实现对中波台站内外环境相关数据采集及相关设备的远程控制。     

基于直接数字频率合成的远距离散射通信方法

远距离(LoRa)散射通信(BC)不仅成本低、功耗低,而且通信距离远。但现存散射方案的系统组成复杂,且无法应用于实际工程。为此该文提出一种新的LoRa散射通信方法,采用直接数字频率合成(DDS)技术产生频率线性变化的方波作为LoRa散射调制信号,并据此首次展示了基于MCU的LoRa散射通信系统原型样机。实验结果表明,该方法能够在相距208 m的基站和接收端之间的任意位置实现低功耗LoRa散射通信,且兼容现有的商用LoRa射频芯片组。此外,该方法还适用于专用集成电路(ASIC)设计,可使LoRa散射IC有更高的鲁棒性、更低的成本和功耗。     

A New Method to Find a High Reliable Route in IoT by Using Reinforcement Learning and Fuzzy Logic

Recently, Internet is moving quickly toward the interaction of objects, computing devices, sensors, and which are usually indicated as the Internet of things (IoT). The main monitoring infrastructure of IoT systems main monitoring infrastructure of IoT systems is wireless sensor networks. A wireless sensor network is composed of a large number of sensor nodes. Each sensor node has sensing, computing, and wireless communication capability. The sensor nodes send the data to a sink or a base station by using wireless transmission techniques However, sensor network systems require suitable routing structure to optimizing the lifetime. For providing reasonable energy consumption and optimizing the lifetime of WSNs, novel, efficient and economical schemes should be developed. In this paper, for enhancing network lifetime, a novel energy-efficient mechanism is proposed based on fuzzy logic and reinforcement learning. The fuzzy logic system and reinforcement learning is based on the remained energies of the nodes on the routes, the available bandwidth and the distance to the sink. This study also compares the performance of the proposed method with the fuzzy logic method and IEEE 802.15.4 protocol. The simulations of the proposed method which were carried out by OPNET (Optimum Network performance) indicated that the proposed method performed better than other protocols such as fuzzy logic and IEEE802.15.4 in terms of power consumption and network lifetime.

     

基于物联网和光电子技术的环境自动检测仪器和系统

为满足环境监测预警体系建设的需求,系统集成嵌入式技术、全光谱检测技术、电子舌检测技术,研制了基于物联网和光电子技术的环境自动检测系统,实现对pH、电导率、氨氮、浊度、色度、COD的在线检测。经实验验证系统性能良好,pH、电导率、氨氮、浊度和COD的测量精度分别为-0.02, 0.4%, 2.9%, 2.1%, 1.1%; 电导率、浊度、COD的测量检出限分别为0.7 μS/cm, 0.9NTU, 0.5 mg/L。实际水样比对测试符合要求,可满足水质在线快速监测的需求。     

基于物联网的水质监测系统设计

针对传统水质监测方式中存在的测试周期长、数据反馈速度慢等弊端,本文提出一种智慧型水质实时监测系统。本系统以无线传感器网络、网络摄像机以及各类水质污染监测传感器以及后台数据库为核心,开发具有自愈能力的自组网小型水质监测系统,实现对水产养殖用水的水位、溶解氧、PH值、温度、图像等多参数的采集,并通过无线网络实现传感器检测节点和协调器节点之间数据快速、准确的传输,进而对多参数进行实时远程监测,解决水产养殖业水质实时监测和管理问题。     

物联网燃气表系统的设计与实现

针对现有远程抄表系统的不足,结合计算机及通信领域的最新科技成果,提出了一种基于LoRa(Long Range)和GPRS(General Packet Radio Service)相结合的网络化远程抄表系统。其无线智能燃气表终端采用超低功耗微处理器MSP430进行智能化设计,完成气表数据采集与处理;采用LoRa技术进行测控组网;集中器和管理中心通过GPRS无线通信网络实现数据的远程交互。最后,给出了抄表系统的可靠性解决方案。实验结果表明,该系统比传统的远程抄表系统能耗低,且更快捷、可靠、方便,可广泛应用于无线远程抄表领域。     

Energy-efficient digital and wireless IC design for wireless smart sensing

Wireless smart sensing is now widely used in various applications such as health monitoring and structural monitoring. In conventional wireless sensor nodes, significant power is consumed in wirelessly transmitting the raw data. Smart sensing adds local intelligence to the sensor node and reduces the amount of wireless data transmission via on-node digital signal processing. While the total power consumption is reduced compared to conventional wireless sensing, the power consumption of the digital processing becomes as dominant as wireless data transmission. This paper reviews the state-of-the-art energy-efficient digital and wireless IC design techniques for reducing the power consumption of the wireless smart sensor node to prolong battery life and enable self-powered applications.     

基坑监测系统中传感网的节点部署

基坑监测系统中,需要在各监测点部署传感器节点,系统的监测点围绕基坑工程展开,其监控区域近似圆环。在基站收集监测数据时,离基站越近的区域需要转发的数据越多,节点能量消耗速度也就越快,基站附近的节点将很快消耗完能量,系统随即瘫痪。通过研究圆环形传感网的拓扑特点,得到节点密度公式,使得各区域的总能量与能量消耗速度之比达到平衡。理论分析和仿真实验表明,按照此密度公式部署传感器节点,可显著提高系统生命周期。     

Adaptive Load-Aware Congestion Control Protocol for Wireless Sensor Networks

Congestion control in wireless sensor networks (WSNs) is crucial. In this article, we discuss congestion control and the adaptive load-aware problem for sensor nodes in WSNs. When the traffic load of a specific node exceeds its the available capacity of the node, a congestion problem occurs because of buffer memory overflow. Congestion may cause serious problems such as packet loss, the consumption of power, and low network throughput for sensor nodes. To address these problems, we propose a distributed congestion control protocol called adaptive load-aware congestion control protocol (ALACCP). The protocol can adaptively allocate the appropriate forwarding rate for jammed sensor nodes to mitigate the congestion load. Through the buffer management mechanism, the congestion index of neighboring sensor nodes, and an adjustment of the adaptive forwarding rate, the degree of congestion is alleviated markedly. The performance in allocating the forwarding rate effectively to neighboring sensor nodes also improves. The ALACCP can avoid packet loss because of traffic congestion, reduce the power consumption of nodes, and improve the network throughput. Simulation results revealed that the proposed ALACCP can effectively improve network performance and maintain the fairness of networks.     

Cluster head selection for energy efficient and delay-less routing in wireless sensor network

Wireless sensor network (WSN) is comprised of tiny, cheap and power-efficient sensor nodes which effectively transmit data to the base station. The main challenge of WSN is the distance, energy and time delay. The power resource of the sensor node is a non-rechargeable battery. Here the greater the distance between the nodes, higher the energy consumption. For having the effective transmission of data with less energy, the cluster-head approach is used. It is well known that the time delay is directly proportional to the distance between the nodes and the base station. The cluster head is selected in such a way that it is spatially closer enough to the base station as well as the sensor nodes. So, the time delay can be substantially reduced. This, in turn, the transmission speed of the data packets can be increased. Firefly algorithm is developed for maximizing the energy efficiency of network and lifetime of nodes by selecting the cluster head optimally. In this paper firefly with cyclic randomization is proposed for selecting the best cluster head. The network performance is increased in this method when compared to the other conventional algorithms.

     

An Energy Conservation MAC Protocol in Wireless Sensor Networks

Wireless sensor networks use battery-operated computing and sensing devices. Because of the limitation of battery power in the sensor nodes, energy conservation is a crucial issue in wireless sensor networks. Consequently, there is much literature presenting energy-efficient MAC protocols based on active/sleep duty cycle mechanisms to conserve energy. Convergecast is a common communication pattern across many sensor network applications featuring data gathering from many different source nodes to a single sink node. This leads to high data collision rates, high energy consumption, and low throughput near the sink node. This paper proposes an efficient slot reservation MAC protocol to reduce energy consumption and to make transmission more efficient in data gathering wireless sensor networks. The simulation results show that our protocol provides high throughput, low delivery latency and low energy consumption compared to other methods.

LoRa在电子价签系统中的应用与实现

传统无线局域网组网方式存在通信距离近、功耗高等问题，不能满足大型超市电子价签系统的通信要求。为此，提出一种基于LoRa（Long Range）通信技术的电子价签系统设计方案。采用具备LoRa调制方式的SX1278芯片作为系统LoRa模块的主芯片，以STM32单片机作为网关和节点价签的主控MCU，采用星型拓扑结构组网，并通过对通信过程中信噪比和接收信号强度两个参数值进行融合计算来分析信道状态，以此实现对数据传输速率的自适应调整。经实验测试，该系统通过服务器可经LoRa无线网络稳定传输数据，最终对电子价签显示内容进行更改，并有效提高了通信距离和降低功耗，可满足大型超市的实际需求。     

基于无线射频和GPRS网络的林火监测数据采集电路设计

本监测系统利用无线射频与GPRS网络相结合的方式,监测终端将温度传感器与烟雾浓度传感器采集到的数据通过无线射频发送到基站,再通过基站的GPRS网络将数据发送到监控中心,来实现对林火的实时监测。通过监控中心对整个网络的控制,可以实时监测森林的状况。本监测系统结合无线射频和GPRS网络的优势,无线射频使监测终端更加方便安装,GPRS网络可以实现远程监控管理。本监测系统可以通过短信、服务器、定时和报警触发方式启动,可以实时采集现场数据。本设计的硬件电路以LPC767芯片为核心,采用RF200无线射频芯片和MC55模块进行了各种外围电路设计,采取了低功耗与抗干扰措施。制作出了电路板,并且完成了部分功能的测试。     

Energy awareness workflow model for wireless sensor nodes

Before the development of a large‐scale wireless sensor network (WSN) infrastructure, it is necessary to create a model to evaluate the lifespan of the infrastructure, the system performance and the cost so that the best design solution can be obtained. Energy consumption is an important factor that influences the lifespan of WSNs. One of the ways to extend the lifespan of WSNs is to design wireless sensor nodes with low power consumption. This involves component selection and the optimisation of hardware architecture, monitoring software system and protocols to satisfy the requirements of the particular applications. This paper proposes a comprehensive model to describe the workflow of a wireless sensor node. Parameter setup and energy consumption calculation are demonstrated through the model simulation. It provides a mathematical approach to dynamically evaluate the energy consumption of a sensor node. This will benefit the development of wireless sensor nodes based on microprocessors with limited computational capability. Therefore, the model can be applied in dynamic power management systems for wireless sensor nodes or in wireless communication protocols with energy awareness, in particular, for WSNs with self‐organisation. More importantly, the generalisation of the model may be employed as a standard paradigm for the development of wireless sensor node with energy awareness. Copyright © 2012 John Wiley & Sons, Ltd.     

基于云计算的矿井无线传感网络火情远程监控系统

针对矿井实际需求情况,提出了一种基于云计算的无线传感网络火情远程监控系统,此系统包括通讯基站、无线传感器网络和云计算平台,其中,无线传感器网络通过通讯基站与云计算平台相连接。它包括用于采集煤矿安全数据的无线传感器、执行器和用于传输煤矿安全数据的无线网关。该系统具备低成本、自组织、低功耗、信息交互方便的特点,具有很好的应用前景。     

基于GF-1影像的巢湖浊度遥感监测及时空变化研究

浊度监测可以为湖泊水质的污染防控和预警提供科学依据.为了提高湖泊浊度的动态监测能力,将卫星遥感监测和浮标检测站监测相结合,对2019年巢湖浊度的时空变化进行分析.浮标检测站监测通过高频次连续的实测浊度数据的统计分析,研究巢湖浊度时空变化特征;遥感监测通过构建最优波段组合模型对浊度进行定量反演.研究结果表明:(1)巢湖整...     

REACA: An Efficient Protocol Architecture for Large Scale Sensor Networks

The emergence of wireless sensor networks has imposed many challenges on network design such as severe energy constraints, limited bandwidth and computing capabilities. This kind of networks necessitates network protocol architectures that are robust, energy-efficient, scalable, and easy for deployment. This paper proposes a robust energy-aware clustering architecture (REACA) for large-scale wireless sensor networks. We analyze the performance of the REACA network in terms of quality-of-service, asymptotic throughput capacity, and power consumption. In particular, we study how the throughput capacity scales with the number of nodes and the number of clusters. We show that by exploiting traffic locality, clustering can achieve performance improvement both in capacity and in power consumption over general-purpose ad hoc networks. We also explore the fundamental trade-off between throughput capacity and power consumption for single-hop and multi-hop routing schemes in cluster-based networks. The protocol architecture and performance analysis developed in this paper provide useful insights for practical design and deployment of large-scale wireless sensor network.