Abstract: Many industrial/scientific/medical (ISM) band radio frequency (RF) products use crystal oscillators to generate areference for the phase-locked loop (PLL)-based local oscillator (LO). This tutorial provides a basic description of theISM-RF Crystal Calculator, which can be used to calculate various impacts on crystal frequency accuracy and startupmargin for such an LO.
上传时间: 2013-11-15
上传用户:JasonC
Abstract: Alexander Graham Bell patented twisted pair wires in 1881. We still use them today because they work so well. In addition we have the advantage ofincredible computer power within our world. Circuit simulators and filter design programs are available for little or no cost. We combine the twisted pair and lowpassfilters to produce spectacular rejection of radio frequency interference (RFI) and electromagnetic interference (EMI). We also illustrate use of a precision resistorarray to produce a customizable differential amplifier. The precision resistors set the gain and common mode rejection ratios, while we choose the frequencyresponse.
上传时间: 2014-11-26
上传用户:Vici
Abstract: This reference design provides a complete demonstration platform for using industrial/scientific/medical radio frequency
上传时间: 2013-11-09
上传用户:LP06
Abstract: Impedance mismatches in a RADio-frequency (RF) electrical transmission line cause power loss andreflected energy. Voltage standing wave ratio (VSWR) is a way to measure transmission line imperfections. Thistutorial defines VSWR and explains how it is calculated. Finally, an antenna VSWR monitoring system is shown.
上传时间: 2013-10-19
上传用户:yuanwenjiao
介绍一种简单射频识别系统设计。该设计包括阅读器、应答器和线圈3部分。由单片机控制阅读器向应答器发射无线信号,并接收应答器回送的信号,再通过分析回送信号识别物品。阅读器和应答器之间以半双工通信方式通信。 Abstract: A simple design of radio frequency identification system is given in this paper.The design includes reader,responder and winding.Through MCU,signals are sent to responder from reader,then corresponding signals are sent back. According to the analysis of the signals sent back,the objects can be identified.Half-duplex communication is adopted? between? reader? and? responder.
上传时间: 2013-10-11
上传用户:plsee
Microchip ZigBee协议栈:ZigBee™ 是专为低速率传感器和控制网络设计的无线网络协议。有许多应用可从ZigBee 协议受益,其中可能的一些应用有:建筑自动化网络、住宅安防系统、工业控制网络、远程抄表以及PC 外设。与其他无线协议相比, ZigBee 无线协议提供了低复杂性、缩减的资源要求,最重要的是它提供了一组标准的规范。它还提供了三个工作频带,以及一些网络配置和可选的安全功能。如果您正在寻求现有的控制网络技术(例如RS-422、RS-485)或专有无线协议的替代方案, ZigBee 协议可能是您所需的解决方案。此应用笔记旨在帮助您在应用中采用ZigBee 协议。 可以使用在应用笔记中提供的Microchip ZigBee 协议栈快速地构建应用。为了说明该协议栈的用法,本文包含了两个有效的演示应用程序。可将这两个演示程序作为参考或者根据您的需求经过简单修改来采用它们。此应用笔记中提供的协议栈函数库实现了一个与物理层无关的应用程序接口。 因此,无需做重大修改就可以轻松地在射频(Radio Frequency,RF)收发器之间移植应用程序。在此文档末尾的“常见问题解答”中提供了有关Microchip 协议栈和用法的一些常见问题及其答案。
上传时间: 2013-10-08
上传用户:u789u789u789
Abstract: Many industrial/scientific/medical (ISM) band radio frequency (RF) receivers use an external Sallen-Key datafilter and a data slicer to generate the baseband digital output. This tutorial describes the ISM-RF Baseband Calculator,which can be used to calculate the filter capacitor values and the data slicer RC components, while providing a visualexample of the baseband signals.
上传时间: 2013-11-04
上传用户:jkhjkh1982
RFID(Radio Frequency Identification)技术是利用射频通信实现的一种非接触式自动识别技术。拥有广阔的发展前景和巨大的市场潜力。本文介绍了RFID技术的原理、特点,深入分析了信号传输时所采取的反方向散射的调制方式,影响传输距离的因素,最后介绍了在远程RFID自动识别系统中的读写冲突和防冲突算法,更好的解决了远程RFID系统存在的冲突问题。
上传时间: 2013-10-11
上传用户:fdfadfs
Abstract: This application note describes system-level characterization and modeling techniques for radio frequency (RF) and microwavesubsystem components. It illustrates their use in a mixed-signal, mixed-mode system-level simulation. The simulation uses an RF transmitterwith digital predistortion (DPD) as an example system. Details of this complex system and performance data are presented.
上传时间: 2013-12-18
上传用户:onewq
Abstract: With industrial/scientific/medical (ISM) band radio frequency (RF) products, often times users are new to the structure of Maxim's low pin-count transmitters andfully integrated superheterodyne receivers. This tutorial provides simple steps that can be taken to get the best performance out of these transmitters and receivers whileproviding techniques to measure the overall capability of the design.
上传时间: 2013-11-02
上传用户:yph853211