Free Space Optical Communication (FSOC) is an effective alternative technology to meet the Next Generation Network (NGN) demands as well as highly secured (mili- tary) communications. FSOC includes various advantages like last mile access, easy installation, free of Electro Magnetic Interference (EMI)/Electro Magnetic Compatibil- ity (EMC) and license free access etc. In FSOC, the optical beam propagation in the turbulentatmosphereisseverelyaffectedbyvariousfactorssuspendedinthechannel, geographicallocationoftheinstallationsite,terraintypeandmeteorologicalchanges. Therefore a rigorous experimental study over a longer period becomes significant to analyze the quality and reliability of the FSOC channel and the maximum data rate that the system can operate since data transmission is completely season dependent.
标签： Communication Optical System Space Free
上传时间： 2020-05-27
上传用户：shancjb
From its inception, random matrix theory has been heavily influenced by its applications in physics, statistics and engineering. The landmark contributions to the theory of random matrices of Wishart (1928) [311], Wigner (1955) [303], and Mar˘ cenko and Pastur (1967) [170] were moti- vated to a large extent by practical experimental problems.
上传时间： 2020-06-01
上传用户：shancjb
The first practical examples of mobile communications were used in many countries like the USA, the UK and Germany in military services, and played a significant role in the First World War to transfer important information from the front to headquarters to take further actions. Good and secure wireless communications were an important need for all military services – army, navy and air force. In this respect, the Second World War was a big experimental battlefield for the development and evolution of mobile radio. It was in the interests of governments that after the Second World War the military investment should be paid back by civilian use, and all western European countries started their so-called first generation of mobile communication networks.
标签： Multimedia Business Mobile The
上传时间： 2020-06-01
上传用户：shancjb
Describing the relevant detection and estimation theory, this detailed guide provides the background knowledge needed to tackle the design of practical WLAN positioning systems. It sets out key system-level challenges and design considerations in increasing positioningaccuracyandreducingcomputationalcomplexity,examinesdesigntradeoffs, and presents experimental results.
标签： Positioning Systems WLAN
上传时间： 2020-06-01
上传用户：shancjb
对某四轮独立驱动电动汽车轮毂电机进行研究,设计一种永磁无刷直流电机控制器.以STM32F103RBT6芯片为基础,对电机驱动电路、采样电路和保护电路分别进行硬件设计与分析;同时,采用模块化软件设计方案,对该控制器的软件系统进行升级.实验验证表明:所设计的电机控制器能使电机响应迅速、转速稳定、无超调,且电动车动力输出性能良好.A permanent magnet brushless direct current motor controller was designed by studying the hub motor of a four-wheel independent drive electric vehicle.Based on STM32 F103RBT6 chip,the hardware design and analysis of motor drive circuit,sampling circuit and protection circuit were carried out respectively.At the same time,modular software design scheme was adopted to upgrade the software system of the controller.experimental results show that the designed motor controller can ensure the motor fast response,stable speed,no overshoot,and good power output performances.
上传时间： 2022-03-26
上传用户：qingfengchizhu
随着光伏发电系统快速发展,以及电动汽车充电桩的普及,传统的剩余电流保护器无法满足实际需求。介绍了一款B型剩余电流保护器,采用磁调制剩余电流互感器和零序电流互感器采集剩余电流。根据GB/T 22794—2017标准要求,可识别1 kHz及以下的正弦交流、带和不带直流分量的脉动直流、平滑直流等剩余电流信号。经信号调理电路将电压信号送到单片机进行采集和判断。通过试验测试,该样机在测试精度和速度上均符合国家标准的相关要求。The rapid development of photovoltaic power generation systems and the popularity of electric vehicle charging piles make the traditional residual current protective devices unable to meet the actual demand.This paper proposed a type B residual current protective device,which uses the magnetically modulated residual current transformer and the zero sequence current transformer to acquire the residual current.According to the requirements of GB/T 22794—2017,the type B residual current protective device can detect sinusoidal AC residual current of 1kHz and below 1kHz,pulsating DC residual current with and without DC component,smooth DC residual current and so on.The signal processing circuit sends the voltage signal to the MCU for acquisition and judgment.Through experimental tests,the device meets the relevant requirements of national standards in terms of test accuracy and speed.
标签： 电流保护器
上传时间： 2022-03-27
上传用户：
设计了自动控制系统综合实验案例“基于LabVIEW和单片机的温度控制系统设计”。实验系统硬件部分由单片机、温度传感器、D/A转换模块、调压模块和电烤箱组成,设计了单片机与各个模块之间的接口电路。软件部分采用LabVIEW软件实现控制算法,并设计监控界面实现参数设定、温度数据实时监控等功能。设计了单片机与LabVIEW软件之间的串口通信程序,实现了输入、输出数据的传输。通过综合实验系统设计,使学生得到控制系统设计和实验调试等综合能力的训练。A comprehensive experimental case of the automatic control system is presented,which is the design of the temperature control system based on LabVIEW and SCM.The hardware part of the experimental system is composed of the SCM,temperature sensor,D/A conversion module,voltage regulating module and electric oven.The interface circuit between the SCM and each module is designed.In the software part,LabVIEW software is used to realize the control algorithm,and the monitoring interface is designed to realize the functions of parameter setting,temperature data real-time monitoring,etc.The serial communication program between the SCM and LabVIEW software is designed to realize the transmission of input and output data.Through the design of this comprehensive experimental system,students can get the comprehensive ability training for the control system design,experiment debugging,etc.
上传时间： 2022-03-27
上传用户：qdxqdxqdxqdx
实验教学一直是工科教学中不可或缺的组成部分,对培养学生的动手能力,独立思考能力,创新思维与发散思维具有重要的作用。针对目前电路教学实验中电路仿真实验与实物电路实验各自独立,无法统一问题,提出将仿真电路实验与实物电路实验有机的结合同步操作,并使用Web发布实现远程实验操作。采用Multisim作为电路实验仿真平台,NI Eiviss II作为实物电路实验硬件平台,运用LabVIEW整合Multisim电路仿真实验与实物电路实验,实现仿真与实物实验有机结合,两种实验可同步进行。学生在仿真实验中先可探索实验,然后做实物实验。同时运用LabVIEW开发出实验过程人机交互操作接口界面,使用过程中效果良好。experimental teaching has always been an indispensable part of engineering education.And it always plays an important role in cultivating students'practical ability,independent thinking ability,innovative thinking and divergent thinking.But simulation experiment and physical experiment cannot be unified in the circuit teaching experiment at present.In order to solve this problem,this paper proposes to combine organically the simulation circuit experiment with physical circuit experiment,and synchronously operate them.This paper uses the WEB publishing to achieve remote experimental operation.Multisim is used as the circuit simulation platform,and NI Eiviss II is used as the physical circuit hardware platform.Multisim circuit simulation experiment and physical circuit experiment are implemented by LabVIEW to realize the combination of simulation experiment and physical experiment.Students do explore experiments in simulation experiment firstly,and then do physical experiment.And this paper uses LabVIEW to develop the experimental man-machine interface.
上传时间： 2022-04-05
上传用户：
针对目前MSP430单片机实验装置较少、实验内容少,而且无MSP430高端产品的实验装置,研制了基于MSP430F5529单片机的综合实验装置,主要包括MSP430 Launch Pad和母板两部分。较传统的单片机实验装置增加了模拟电路的设置,设计的实验能够利用单片机的所有外设,可进行模块基础实验和综合实验两大类实验,非常适合自动化和电气信息类大学生学习使用。Concerning with the lack of experimental equipment and content based on MSP430,and especially,the experimental equipment of MSP430 senior products,an experimental equipment based on MSP430F5529 microcontroller is developed. It mainly consists of two parts： MSP430 Launch Pad and main board. Compared with traditional microcontroller experiment equipment,a few analog circuits were added. The experiment we set up takes advantage of all microcontroller peripherals. Students can do two kinds of experiments： module experiment and complex experiment.Therefore it fits university students in automation and electrical major very well.
标签： msp430f5529 单片机
上传时间： 2022-04-13
上传用户：
为了提高超高频RFID系统中阅读器在低信噪比的情况下仍具有较高的识别能力,提出一种基于FPGA系统结合软件无线电方法实现超高频RFID射频前端电路方案。超高频射频识别系统必须符合EPC Class 1generation 2标准,所设计的电路系统以Xilinx公司的XC6SLX16-2CSG324FPGA芯片为硬件基础,将数字基带调制解调和中频滤波电路在FPGA系统中设计实现,重点阐述了射频前端电路的设计结构、AD/DA转换电路,以及数字滤波器的设计。实验结果表明,所设计的超高频RFID阅读器简化了前端电路系统结构,提升了稳定性,增强了抗干扰能力。该电路系统在信噪比较低的情况下,能够较好地实现915MHz频率的射频接收和发送。In order to improve the reader UHF RFID system still has a higher ability to identify,in the case of low signal-to-noise ratio.The UHF RFID systems must comply with EPC Class 1 generation 2 standard.In this paper,the design of the circuit system based on Xilinx＇s XC6SLX16-2CSG324 FPGA chip,and presents UHF RFID RF front-end circuit with software radio based on FPGA system.Digital baseband modem and IF filter circuit is designed and implemented in the FPGA system,and focused on designing the structure of the RF front-end circuit,AD/DA conversion circuits,and digital filter.experimental results show that the UHF RFID reader de...
标签： 915mhz 超高频 rfid 阅读 射频 前端 电路 设计
上传时间： 2022-04-17
上传用户：shjgzh
