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
The Raspberry Pi has become a computing phenomenon. This single-board miniature computer, first released in February 2012 by the Raspberry Pi Foundation, has grown into a series of nearly a dozen models that have sold a total of more than 10 million units in five years. Inexpensive to buy and to run, Raspberry Pi computers are great for enthusiasts, good for games, and fun for children. Raspberry Pi computers are also terrific in the classroom, enabling you to put on each desk an easily-manageable computer on which students can do everything from learning Internet use and essential office software skills, through grasping programming basics in an easy-to-learn format, to performing full-on programming in Python, Java, C, and other languages. Better yet, you can install all the software needed for those activities automatically alongside the operating system.
标签： Deploying Classroom Raspberry the Pi in
上传时间： 2020-06-06
上传用户：shancjb
LIKE SO MANY OTHERS , THIS BOOK WAS WRITTEN BECAUSE WE COULDN ’ T FIND ONE LIKE IT . We needed something to hand to all of those people who have come to us asking for “a good book to read on RFID.” When we looked for candidates we found some great books, but most were aimed at electrical engineers or top-level managers, with very little for those of us who are in between. This book is for developers, system and software architects, and project managers, as well as students and professionals in all of the industries impacted by Radio Frequency Identification (RFID) who want to understand how this technology works. As the title suggests, this book is about RFID in general and not just the most recent developments; however, because so much is going on in the area of RFID for the supply chain and especially the Electronic Product Code (EPC), we have devoted consider- able space to these topics. Regardless of the type of RFID work you may be doing, we think you will find something useful here.
标签： Essentials RFID
上传时间： 2020-06-08
上传用户：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.
标签： Fundamentals_of_Global_Positionin g_System
上传时间： 2020-06-09
上传用户：shancjb
This book is a general introduction to machine learning that can serve as a reference book for researchers and a textbook for students. It covers fundamental modern topics in machine learning while providing the theoretical basis and conceptual tools needed for the discussion and justification of algorithms. It also describes several key aspects of the application of these algorithms.
标签： Foundations Learning Machine 2nd of
上传时间： 2020-06-10
上传用户：shancjb
The PW4556 series of devices are highly integrated Li-Ion and Li-Pol linear chargers targetedat small capacity battery for portable applications. It is a complete constant-current/ constantvoltage linear charger. No external sense resistor is needed, and no blocking diode is required dueto the internal MOSFET architecture. It can deliver up to 300mA of charge current (using a goodthermal PCB layout) with a final float voltage accuracy of ±1%. The charge voltage is fixed at 4.2V or4.35V, and the charge current can be programmed externally with a single resistor. The chargerfunction has high accuracy current and voltage regulation loops and charge termination
标签： pw4556
上传时间： 2022-02-11
上传用户：1208020161
The PW4055 is a complete constant-current /constant-voltage linear charger for single cell lithiumion batteries.Its ThinSOT package and low external component count make the PW4055 ideallysuited for portable applications.Furthermore, the PW4055 is specifically designed to work within USBpower specifications.The PW4055 No external sense resistor is needed, and no blocking diode is required due to theinternal MOSFET architecture.Thermal feedback regulates the charge current to limit the dietemperature during high power operation or high ambient temperature. The charge voltage is fixedat 4.2V, and the charge current can be programmed externally with a single resistor. The PW4055automatically terminates the charge cycle when the charge current drops to 1/10th the programmedvalue after the final float voltage is reached. When the input supply (wall adapter or USB supply) isremoved, the PW4055 automatically enters a low current state, dropping the battery drain currentto less than 2µA. The PW4055 can be put into shutdown mode, reducing the supply current to 25µA.The BAT pin has a 7KV ESD(HBM) capability. Other features include charge current monitor, undervoltage lockout, automatic recharge and a status pin to indicate charge termination and the presenceof an input voltage
标签： pw4055
上传时间： 2022-02-11
上传用户：jason_vip1
本设计介绍了一种基于STM32单片机控制的智能水杯,可利用插口式电源或无线充电底座为加热器提供能量,并在达到某种饮品所需温度时进行保温。水杯内置充电电池,可选用USB接口或无线充电。在水杯内部设置无线模块,用户利用手机App与水杯进行匹配进行加热操作,加热完后水杯会通过手机App和液晶显示屏实时反馈液体温度,通过指示灯显示电量情况等,给用户进行提醒。该智能水杯设计创新,实用价值较高。This paper introduces an intelligent water cup based by STM32 microcontroller,it can provide energy for the heater by socket type power supply or wireless charging base,and hold temperature needed for some kind of drink.Builtedin rechargeable battery,water cup can use USB or wireless charging.The wireless module is set up inside it,and customers can use mobile App to match and heat.After heating,water cup feeds back liquid temperature through the mobile App,and then displays on LCD,reminds users through the indicator light.The intelligent water cup is designed innovatively and has high practical value.
上传时间： 2022-03-28
上传用户：
电学中的测量技术涉及范围非常广,电流测量在电学计量中占有非常重要的位置。如何精确地进行电流测量是精密测量的一大难题。传统的电流检测电路多采用运算放大芯片与片外电流检测电路相结合的方式,电路集成度很低,需要较多的接口和资源才能完成对电路的检测。本文把所有电路部分都集成在一块芯片上,包括检测电阻,运算放大器电路及模拟转数字转换电路,从而在电路内部可以进行电流检测,使电路更好的集成化。前置电路使用二级共源共栅结构的运算放大器,减小沟道长度调制效应造成的电流误差。10位SAR ADC中采用电容驱动能力强的传输门保证了模数转化器的有效精度。比较器模块采用再生锁存器与迟滞比较器作为基础单元组合解决精密测量的问题。本设计可以作为嵌入芯片内的一小部分而检测芯片中的微小电流1mA~100mA,工作电压在1.8v左右,电流检测精度预期达到10uA的需求。The measurement technology in electricity involves a wide range,and current measurement plays a very important position in electrical measurement.How to accurately measure current is a big problem in precision measurement. The traditional current detecting circuit adopts the combination of the operational amplifier chip and theoff-chip current detecting circuit, The circuit integration is very low, and more interfaces and resources are needed tocomplete the circuit detection.This topic integrates all the circuit parts into one chip, including detection resistance, operational amplifier circuit andanalog to digital conversion circuit. Highly integrated circuit makes the external resources on the chip more intensive,so that current detection can be carried out inside the circuit, so that the circuit can be better integrated. Thefront-end circuit of this project uses two-stage cascade operational amplifier and cascade tube to reduce the currenterror caused by channel length modulation effect. In 10-bit SAR ADC, the transmission gate with strong capacitivedriving ability ensures the effective accuracy of the analog-to-digital converter. Comparator module uses regenerativelatch and hysteresis comparator as basic unit to solve the difficult problem of precision measurement. This topic can beused as a small part of the embedded chip to detect the micro-current in the chip 1 mA~100 mA, the working voltageis about 1.8v, and the current detection accuracy is expected to reach the requirement of 10 uA.
上传时间： 2022-04-03
上传用户：
The GL823K integrates a high speed 8051 microprocessor and a high efficiency hardware engine for the best data transfer performance between USB and flash card interfaces. Its pin assignment design fits to card sockets to provide easier PCB layout. Inside the chip, it integrates 5V to 3.3V regulator, 3.3V to 1.8V regulator and power MOSFETs and it enables the function of on-chip clock source (OCCS) which means no external 12MHz XTAL is needed and that effectively reduces the total BOM cost.
上传时间： 2022-04-27
上传用户：qdxqdxqdxqdx
