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.
標簽： Communication Optical System Space Free
上傳時間： 2020-05-27
上傳用戶：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.
上傳時間： 2020-06-01
上傳用戶：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.
標簽： Multimedia Business Mobile The
上傳時間： 2020-06-01
上傳用戶：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.
標簽： Positioning Systems WLAN
上傳時間： 2020-06-01
上傳用戶：shancjb
對某四輪獨立驅動電動汽車輪轂電機進行研究,設計一種永磁無刷直流電機控制器.以STM32F103RBT6芯片為基礎,對電機驅動電路、采樣電路和保護電路分別進行硬件設計與分析;同時,采用模塊化軟件設計方案,對該控制器的軟件系統進行升級.實驗驗證表明:所設計的電機控制器能使電機響應迅速、轉速穩定、無超調,且電動車動力輸出性能良好.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.
上傳時間： 2022-03-26
上傳用戶：qingfengchizhu
隨著光伏發電系統快速發展,以及電動汽車充電樁的普及,傳統的剩余電流保護器無法滿足實際需求。介紹了一款B型剩余電流保護器,采用磁調制剩余電流互感器和零序電流互感器采集剩余電流。根據GB/T 22794—2017標準要求,可識別1 kHz及以下的正弦交流、帶和不帶直流分量的脈動直流、平滑直流等剩余電流信號。經信號調理電路將電壓信號送到單片機進行采集和判斷。通過試驗測試,該樣機在測試精度和速度上均符合國家標準的相關要求。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.
標簽： 電流保護器
上傳時間： 2022-03-27
上傳用戶：
設計了自動控制系統綜合實驗案例“基于LabVIEW和單片機的溫度控制系統設計”。實驗系統硬件部分由單片機、溫度傳感器、D/A轉換模塊、調壓模塊和電烤箱組成,設計了單片機與各個模塊之間的接口電路。軟件部分采用LabVIEW軟件實現控制算法,并設計監控界面實現參數設定、溫度數據實時監控等功能。設計了單片機與LabVIEW軟件之間的串口通信程序,實現了輸入、輸出數據的傳輸。通過綜合實驗系統設計,使學生得到控制系統設計和實驗調試等綜合能力的訓練。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.
上傳時間： 2022-03-27
上傳用戶：qdxqdxqdxqdx
實驗教學一直是工科教學中不可或缺的組成部分,對培養學生的動手能力,獨立思考能力,創新思維與發散思維具有重要的作用。針對目前電路教學實驗中電路仿真實驗與實物電路實驗各自獨立,無法統一問題,提出將仿真電路實驗與實物電路實驗有機的結合同步操作,并使用Web發布實現遠程實驗操作。采用Multisim作為電路實驗仿真平臺,NI Eiviss II作為實物電路實驗硬件平臺,運用LabVIEW整合Multisim電路仿真實驗與實物電路實驗,實現仿真與實物實驗有機結合,兩種實驗可同步進行。學生在仿真實驗中先可探索實驗,然后做實物實驗。同時運用LabVIEW開發出實驗過程人機交互操作接口界面,使用過程中效果良好。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.
上傳時間： 2022-04-05
上傳用戶：
針對目前MSP430單片機實驗裝置較少、實驗內容少,而且無MSP430高端產品的實驗裝置,研制了基于MSP430F5529單片機的綜合實驗裝置,主要包括MSP430 Launch Pad和母板兩部分。較傳統的單片機實驗裝置增加了模擬電路的設置,設計的實驗能夠利用單片機的所有外設,可進行模塊基礎實驗和綜合實驗兩大類實驗,非常適合自動化和電氣信息類大學生學習使用。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.
標簽： msp430f5529 單片機
上傳時間： 2022-04-13
上傳用戶：
為了提高超高頻RFID系統中閱讀器在低信噪比的情況下仍具有較高的識別能力,提出一種基于FPGA系統結合軟件無線電方法實現超高頻RFID射頻前端電路方案。超高頻射頻識別系統必須符合EPC Class 1generation 2標準,所設計的電路系統以Xilinx公司的XC6SLX16-2CSG324FPGA芯片為硬件基礎,將數字基帶調制解調和中頻濾波電路在FPGA系統中設計實現,重點闡述了射頻前端電路的設計結構、AD/DA轉換電路,以及數字濾波器的設計。實驗結果表明,所設計的超高頻RFID閱讀器簡化了前端電路系統結構,提升了穩定性,增強了抗干擾能力。該電路系統在信噪比較低的情況下,能夠較好地實現915MHz頻率的射頻接收和發送。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...
標簽： 915mhz 超高頻 rfid 閱讀 射頻 前端 電路 設計
上傳時間： 2022-04-17
上傳用戶：shjgzh
