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.
上傳時間: 2013-11-15
上傳用戶: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.
上傳時間: 2014-11-26
上傳用戶:Vici
Abstract: This reference design provides a complete demonstration platform for using industrial/scientific/medical radio frequency
上傳時間: 2013-11-09
上傳用戶: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.
上傳時間: 2013-10-19
上傳用戶:yuanwenjiao
介紹一種簡單射頻識別系統設計。該設計包括閱讀器、應答器和線圈3部分。由單片機控制閱讀器向應答器發射無線信號,并接收應答器回送的信號,再通過分析回送信號識別物品。閱讀器和應答器之間以半雙工通信方式通信。 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.
上傳時間: 2013-10-11
上傳用戶:plsee
Microchip ZigBee協議棧:ZigBee™ 是專為低速率傳感器和控制網絡設計的無線網絡協議。有許多應用可從ZigBee 協議受益,其中可能的一些應用有:建筑自動化網絡、住宅安防系統、工業控制網絡、遠程抄表以及PC 外設。與其他無線協議相比, ZigBee 無線協議提供了低復雜性、縮減的資源要求,最重要的是它提供了一組標準的規范。它還提供了三個工作頻帶,以及一些網絡配置和可選的安全功能。如果您正在尋求現有的控制網絡技術(例如RS-422、RS-485)或專有無線協議的替代方案, ZigBee 協議可能是您所需的解決方案。此應用筆記旨在幫助您在應用中采用ZigBee 協議。 可以使用在應用筆記中提供的Microchip ZigBee 協議??焖俚貥嫿☉?。為了說明該協議棧的用法,本文包含了兩個有效的演示應用程序??蓪⑦@兩個演示程序作為參考或者根據您的需求經過簡單修改來采用它們。此應用筆記中提供的協議棧函數庫實現了一個與物理層無關的應用程序接口。 因此,無需做重大修改就可以輕松地在射頻(Radio Frequency,RF)收發器之間移植應用程序。在此文檔末尾的“常見問題解答”中提供了有關Microchip 協議棧和用法的一些常見問題及其答案。
上傳時間: 2013-10-08
上傳用戶: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.
上傳時間: 2013-11-04
上傳用戶:jkhjkh1982
RFID(Radio Frequency Identification)技術是利用射頻通信實現的一種非接觸式自動識別技術。擁有廣闊的發展前景和巨大的市場潛力。本文介紹了RFID技術的原理、特點,深入分析了信號傳輸時所采取的反方向散射的調制方式,影響傳輸距離的因素,最后介紹了在遠程RFID自動識別系統中的讀寫沖突和防沖突算法,更好的解決了遠程RFID系統存在的沖突問題。
上傳時間: 2013-10-11
上傳用戶: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.
上傳時間: 2013-12-18
上傳用戶: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.
上傳時間: 2013-11-02
上傳用戶:yph853211