We are in the era of ubiquitous computing in which the use and development of Radio Frequency Iden- tification (RFID) is becoming more widespread. RFID systems have three main components: readers, tags, and database. An RFID tag is composed of a small microchip, limited logical functionality, and an antenna. Most common tags are passive and harvest energy from a nearby RFID reader. This energy is used both to energize the chip and send the answer back to the reader request. The tag provides a unique identifier (or an anonymized version of that), which allows the unequivocal identification of the tag holder (i.e. person, animal, or items).
標(biāo)簽： Identification Wireless
上傳時間： 2020-06-08
上傳用戶：shancjb
If one examines the current literature on GPS receiver design, most of it is quite a bit above the level of the novice. It is taken for granted that the reader is already at a fairly high level of understanding and proceeds from there. This text will be an attempt to take the reader through the concepts and circuits needed to be able to understand how a GPS receiver works from the antenna to the solution of user position.
標(biāo)簽： Fundamentals_of_Global_Positionin g_System
上傳時間： 2020-06-09
上傳用戶：shancjb
Fun. We (your authors) wanted a word to describe our ultimate goal for this book, as well as a word we hope you (our reader) will use to describe it, and that’s the one we chose. There are others goals, of course, but in the end, when you’ve finished the book, we’re hoping you’ll have enjoyed the activities described in these pages. Many books use the Introduction to explain exactly what the book is about, what the reader will learn, what the reader needs (a skill or maybe an item or piece of software), and what the reader will be left with when that last page is completed. And this Introduction will do those things, but … hopefully it’ll make you excited to get started.
標(biāo)簽： Adventures Arduino Station Escape Gemini from
上傳時間： 2020-06-09
上傳用戶：shancjb
I wrote this book so that students, hobbyists, and engineers alike can take advantage of the Arduino platform by creating several projects that will teach them about the engineering process. I also wanted to guide the reader through introductory projects so that they could get a firm grasp on the Arduino Language, and how to incorporate several pieces of hardware to make their own projects. This book offers so much information on the Arduino, not just the basic LED projects but it offers different peripherals such as Ultrasonic sensor, the Xbox? controller, Bluetooth, and much more. This book also teaches the non-engineer to follow a process that will help them in future project (not just Arduino projects).
標(biāo)簽： Engineering Practical Arduino
上傳時間： 2020-06-09
上傳用戶：shancjb
The countless technological advances of the twentieth century require that futureengineering educationemphasizebridging thegapbetweentheoryand the real world.Thisedition hasbeenprepared withparticular attentiontothe needs of undergraduates, especially those who seek a solid foundation in control theory aswellas an ability tobridgethe gapbetween control theory and itsreal- world applications.To help the reader achieve this goal, computer-aided design accuracy checks (CADAC) are used throughout the text to encourage good habits of computerliteracy.Each CADAC uses fundamentalconcepts to ensure the viability of a computer solution.
標(biāo)簽： Analysis Control Linear Design System Fifth and
上傳時間： 2020-06-10
上傳用戶：shancjb
? 如果 PCB 用排線連接，控制排線對應(yīng)的插頭插座必須成直線，不交叉、不扭曲。 ? 連續(xù)的 40PIN 排針、排插必須隔開 2mm 以上。 ? 考慮信號流向，合理安排布局，使信號流向盡可能保持一致。 ? 輸入、輸出元件盡量遠(yuǎn)離。 ? 電壓的元器件應(yīng)盡量放在調(diào)試時手不易觸及的地方。 ? 驅(qū)動芯片應(yīng)靠近連接器。 ? 有高頻連線的元件盡可能靠近，以減少高頻信號的分布參數(shù)和電磁干擾。 ? 對于同一功能或模組電路，分立元件靠近芯片放置。 ? 連接器根據(jù)實際情況必須盡量靠邊放置。 ? 開關(guān)電源盡量靠近輸入電源座。 ? BGA 等封裝的元器件不應(yīng)放于 PCB 板正中間等易變形區(qū) ? BGA 等陣列器件不能放在底面， PLCC 、 QFP 等器件不宜放在底層。 ? 多個電感近距離放置時應(yīng)相互垂直以消除互感。 ? 元件的放置盡量做到模塊化并連線最短。 ? 在保證電氣性能的前提下，盡量按照均勻分布、重心平衡、版面美觀的標(biāo)準(zhǔn)優(yōu)化布局。 ? 按電路模塊進(jìn)行布局，實現(xiàn)同一功能的相關(guān)電路稱為一個模塊，電路模塊中的元件應(yīng)采用就近集 中原則，同時數(shù)字電路和模擬電路分開； ? 定位孔、標(biāo)準(zhǔn)孔等非安裝孔周圍 1.27mm 內(nèi)不得貼裝元、器件，螺釘?shù)劝惭b孔周圍 緊固件安裝孔、橢圓孔及板中其它方孔外側(cè)距板邊的尺寸大于 3mm ； ? 發(fā)熱元件不能緊鄰導(dǎo)線和熱敏元件；高熱器件要均衡分布；
標(biāo)簽： pcb 設(shè)計規(guī)范
上傳時間： 2021-06-25
上傳用戶：xiangshuai
為了提高超高頻RFID系統(tǒng)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(tǒng)結(jié)合軟件無線電方法實現(xiàn)超高頻RFID射頻前端電路方案。超高頻射頻識別系統(tǒng)必須符合EPC Class 1generation 2標(biāo)準(zhǔn),所設(shè)計的電路系統(tǒng)以Xilinx公司的XC6SLX16-2CSG324FPGA芯片為硬件基礎(chǔ),將數(shù)字基帶調(diào)制解調(diào)和中頻濾波電路在FPGA系統(tǒng)中設(shè)計實現(xiàn),重點闡述了射頻前端電路的設(shè)計結(jié)構(gòu)、AD/DA轉(zhuǎn)換電路,以及數(shù)字濾波器的設(shè)計。實驗結(jié)果表明,所設(shè)計的超高頻RFID閱讀器簡化了前端電路系統(tǒng)結(jié)構(gòu),提升了穩(wěn)定性,增強(qiáng)了抗干擾能力。該電路系統(tǒng)在信噪比較低的情況下,能夠較好地實現(xiàn)915MHz頻率的射頻接收和發(fā)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(biāo)簽： 915mhz 超高頻 rfid 閱讀 射頻 前端 電路 設(shè)計
上傳時間： 2022-04-17
上傳用戶：shjgzh
說明： 51單片機(jī)控制fm1702射頻讀卡芯片讀寫mifare1卡全套資料。包括電路圖，pcb板圖，上、下位機(jī)軟件及源碼，stc單片機(jī)下載軟件，各種資料文檔等。(51 SCM control fm1702 RF reader chip card reader mifare1 a full set of data. Including the circuit diagram, pcb board map, the upper and lower-bit machine software and source code, stc SCM download software, all kinds of information documentation.)
標(biāo)簽： 51單片機(jī) fm1702 射頻芯片
上傳時間： 2022-05-27
上傳用戶：
一、RFID簡介1.1RFID概念RFID是Radio Frequency ldentification的縮寫，即射頻識別，常稱為感應(yīng)式電子晶片或近接卡、感應(yīng)卡、非接觸卡、電子標(biāo)簽、電子條碼，等等。RFID技術(shù)是一種非接觸式的自動識別技術(shù)，它通過射頻信號自動識別目標(biāo)對象并獲取相關(guān)數(shù)據(jù)，識別工作無須人工干預(yù)，可工作于各種惡劣環(huán)境。RFID技術(shù)可識別高速運(yùn)動物體并可同時識別多個標(biāo)簽，操作快捷方便。一套完整RFID系統(tǒng)由Reader與Transponder兩部份組成，其動作原理為由Reader發(fā)射一特定頻率之無限電波能量給Transponder，用以驅(qū)動Transponder電路將內(nèi)部之IDCode送出，此時Reader便接收此IDCode。Transponder的特殊在于免用電池、免接觸、免刷卡故不怕臟污，且晶片密碼為世界唯一無法復(fù)制，安全性高、長壽命。RFID的應(yīng)用非常廣泛，目前典型應(yīng)用有動物晶片、汽車晶片防盜器、門禁管制、停車場管制、生產(chǎn)線自動化、物料管理。RFID標(biāo)簽有兩種：有源標(biāo)簽和無源標(biāo)簽。
標(biāo)簽： rfid 倉儲管理系統(tǒng)
上傳時間： 2022-06-25
上傳用戶：qdxqdxqdxqdx
編程器 簡介HDSC CCID Writer是華大半導(dǎo)體針對HC32系列MCU所研發(fā)的編程器，支持對MCU進(jìn)行在線編程及離線編程。該編程器小巧便攜、安全可靠、操作簡單，適用于工程研發(fā)及小批量編程。
上傳時間： 2022-06-25
上傳用戶：
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