IEEE802.15.4技术标准主要面向近距离、低速率、低功耗特性的物联网通信应用场景,该标准规定了LR-WPAN(Low-Rate Wireless Personal Area Network)物理层和媒体访问控制层(MAC)。随着物联网的快速发展,NB-IoT、LoRa、Sigfox、Wi-SUN等...IEEE802.15.4技术标准主要面向近距离、低速率、低功耗特性的物联网通信应用场景,该标准规定了LR-WPAN(Low-Rate Wireless Personal Area Network)物理层和媒体访问控制层(MAC)。随着物联网的快速发展,NB-IoT、LoRa、Sigfox、Wi-SUN等面向低功耗、广覆盖特性的LP-WAN(Low Power-Wide Area Network)通信技术标准应运而生。WiSUN(Wireless Smart Utility Network)协议栈基于802.15.4g物理层通信标准,主要使用900MHz带宽(917-923.5MHz),发射功率从10mW至200mW,在海外主要应用于电力物联网通信。展开更多
In this paper, we propose using ZigBee for Intelligent Transportation System (ITS). Most of the accidents these days are caused because of drivers not knowing the upcoming traffic hurdles like curves, traffic signals,...In this paper, we propose using ZigBee for Intelligent Transportation System (ITS). Most of the accidents these days are caused because of drivers not knowing the upcoming traffic hurdles like curves, traffic signals, railway lines and etc. If drivers come to know about the upcoming signals, curves, and railways lines etc the accidents can be avoided. The aim is to provide drivers with intelligent roads so that they can receive the information about the curves and the traffic signals ahead. After receiving the information about the signals ahead, drivers will be careful;this will help avoid the road accidents. Many researches are taking place in the world in the field of ITS and many useful systems are also built but no system is built using this remarkable ZigBee technology. ZigBee is low cost as compared to other short range wireless technologies which will help reduce the total cost of the system, enabling this system to be deployed in developing countries as well.展开更多
介绍了一种基于Wi-Fi无线通信技术的大功率光功率计的设计原理和实现方法。该光功率计以STM32为微控制器,采用热电堆探测器实现热电转换。它不但能通过ESP8266Wi-Fi模块支持与上位机实现无线通信,并且同时支持USB通信模式。该系统可以在...介绍了一种基于Wi-Fi无线通信技术的大功率光功率计的设计原理和实现方法。该光功率计以STM32为微控制器,采用热电堆探测器实现热电转换。它不但能通过ESP8266Wi-Fi模块支持与上位机实现无线通信,并且同时支持USB通信模式。该系统可以在0.19μm~15.0μm波长范围内实现100 m W~100 W激光功率的连续自动量程切换测量。该光功率计还具备了通过脉冲宽度调制(PWM)与0~5 V模拟信号电压输出方式去反馈控制激光器输出强度,以及外触发功能。测试结果表明,该光功率计不但可以很好地满足工程应用中大功率激光器输出功率的检测与控制,并且实现了基于Wi-Fi无线通信方式的移动式测量。展开更多
文摘IEEE802.15.4技术标准主要面向近距离、低速率、低功耗特性的物联网通信应用场景,该标准规定了LR-WPAN(Low-Rate Wireless Personal Area Network)物理层和媒体访问控制层(MAC)。随着物联网的快速发展,NB-IoT、LoRa、Sigfox、Wi-SUN等面向低功耗、广覆盖特性的LP-WAN(Low Power-Wide Area Network)通信技术标准应运而生。WiSUN(Wireless Smart Utility Network)协议栈基于802.15.4g物理层通信标准,主要使用900MHz带宽(917-923.5MHz),发射功率从10mW至200mW,在海外主要应用于电力物联网通信。
文摘In this paper, we propose using ZigBee for Intelligent Transportation System (ITS). Most of the accidents these days are caused because of drivers not knowing the upcoming traffic hurdles like curves, traffic signals, railway lines and etc. If drivers come to know about the upcoming signals, curves, and railways lines etc the accidents can be avoided. The aim is to provide drivers with intelligent roads so that they can receive the information about the curves and the traffic signals ahead. After receiving the information about the signals ahead, drivers will be careful;this will help avoid the road accidents. Many researches are taking place in the world in the field of ITS and many useful systems are also built but no system is built using this remarkable ZigBee technology. ZigBee is low cost as compared to other short range wireless technologies which will help reduce the total cost of the system, enabling this system to be deployed in developing countries as well.
文摘介绍了一种基于Wi-Fi无线通信技术的大功率光功率计的设计原理和实现方法。该光功率计以STM32为微控制器,采用热电堆探测器实现热电转换。它不但能通过ESP8266Wi-Fi模块支持与上位机实现无线通信,并且同时支持USB通信模式。该系统可以在0.19μm~15.0μm波长范围内实现100 m W~100 W激光功率的连续自动量程切换测量。该光功率计还具备了通过脉冲宽度调制(PWM)与0~5 V模拟信号电压输出方式去反馈控制激光器输出强度,以及外触发功能。测试结果表明,该光功率计不但可以很好地满足工程应用中大功率激光器输出功率的检测与控制,并且实现了基于Wi-Fi无线通信方式的移动式测量。