-
波長信號的解調(diào)是實(shí)現(xiàn)光纖光柵傳感網(wǎng)絡(luò)的關(guān)鍵，基于現(xiàn)有的光纖光柵傳感器解調(diào)方法，提出一種基于FPGA的雙匹配光纖光柵解調(diào)方法，此系統(tǒng)是一種高速率、高精度、低成本的解調(diào)系統(tǒng)，并且通過引入雙匹配光柵有效地克服了雙值問題同時擴(kuò)大了檢測范圍。分析了光纖光柵的測溫原理并給出了該方案軟硬件設(shè)計，綜合考慮系統(tǒng)的解調(diào)精度和FPGA的處理速度給出了基于拉格朗日的曲線擬合算法。
Abstract:
Sensor is one of the most important application of the fiber grating. Wavelength signal demodulating is the key Techniques to carry out fiber grating sensing network， based on several existing methods of fiber grating sensor demodulation inadequate， a two-match fiber grating demodulation method was presented. This system is a high-speed， high precision， low-cost demodulation system. And by introducing a two-match grating effectively overcomes the problem of double value while expands the scope of testing. This paper analyzes the principle of fiber Bragg grating temperature and gives the software and hardware design of the program. Considering the system of demodulation accuracy and processing speed of FPGA，this paper gives the curve fitting algorithm based on Lagrange.
標(biāo)簽：
FPGA
光纖光柵
解調(diào)系統(tǒng)
上傳時間：
2014-07-24
上傳用戶：caiguoqing
-
The #1 Step-by-Step Guide to labviewNow Completely Updated for labview 8!
Master labview 8 with the industry's friendliest, most intuitive tutorial: labview for Everyone, Third Edition. Top labview experts Jeffrey Travis and Jim Kring teach labview the easy way: through carefully explained, step-by-step examples that give you reusable code for your own projects!
This brand-new Third Edition has been fully revamped and expanded to reflect new features and Techniques introduced in labview 8. You'll find two new chapters, plus dozens of new topics, including Project Explorer, AutoTool, XML, event-driven programming, error handling, regular expressions, polymorphic VIs, timed structures, advanced reporting, and much more. Certified labview Developer (CLD) candidates will find callouts linking to key objectives on NI's newest exam, making this book a more valuable study tool than ever.
Not just what to d why to do it!
Use labview to build your own virtual workbench
Master labview's foundations: wiring, creating, editing, and debugging VIs; using controls and indicators; working with data structures; and much more
Learn the "art" and best practices of effective labview development
NEW: Streamline development with labview Express VIs
NEW: Acquire data with NI-DAQmx and the labview DAQmx VIs
NEW: Discover design patterns for error handling, control structures, state machines, queued messaging, and more
NEW: Create sophisticated user interfaces with tree and tab controls, drag and drop, subpanels, and more
Whatever your application, whatever your role, whether you've used labview or not, labview for Everyone, Third Edition is the fastest, easiest way to get the results you're after!
標(biāo)簽：
Everyone
LabVIEW
for
英文
上傳時間：
2013-10-14
上傳用戶：shawvi
-
The main objective of this book is to present all the relevant informationrequired for RF and micro-wave power amplifier design includingwell-known and novel theoretical approaches and practical design Techniquesas well as to suggest optimum design approaches effectively combininganalytical calculations and computer-aided design. This bookcan also be very useful for lecturing to promote the analytical way ofthinking with practical verification by making a bridge between theoryand practice of RF and microwave engineering. As it often happens, anew result is the well-forgotten old one. Therefore, the demonstrationof not only new results based on new technologies or circuit schematicsis given, but some sufficiently old ideas or approaches are also introduced,that could be very useful in modern practice or could contributeto appearance of new ideas or schematic Techniques.
標(biāo)簽：
Amplifier
Microwave
Design
Power
上傳時間：
2013-12-22
上傳用戶：vodssv
-
Abstract: The process of designing a radio system can be complex and often involves many project tradeoffs. Witha little insight, balancing these various characteristics can make the job of designing a radio system easier. Thistutorial explores these tradeoffs and provides details to consider for various radio applications. With a focus on theindustrial, scientific, medical (ISM) bands, the subjects of frequency selection, one-way versus two-way systems,modulation Techniques, cost, antenna options, power-supply influences, effects on range, and protocol selectionare explored.
標(biāo)簽：
無線
上傳時間：
2013-12-13
上傳用戶：eastgan
-
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.
標(biāo)簽：
射頻
仿真
微波系統(tǒng)
建模
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.
標(biāo)簽：
ISM
RF
無線電頻率
上傳時間：
2013-11-02
上傳用戶：yph853211
-
Abstract: While many questions still surround the creation and deployment of the smart grid, the need for a reliablecommunications infrastructure is indisputable. Developers of the IEEE 1901.2 standard identified difficult channel conditionscharacteristic of low-frequency powerline communications and implemented an orthogonal frequency division multiplexing (OFDM)architecture using advanced modulation and channel-coding Techniques. This strategy helped to ensure a robust communicationsnetwork for the smart grid.
標(biāo)簽：
1901.2
OFDM
IEEE
正交頻分復(fù)用
上傳時間：
2013-10-18
上傳用戶：myworkpost
-
同步技術(shù)是跳頻通信系統(tǒng)的關(guān)鍵技術(shù)之一，尤其是在快速跳頻通信系統(tǒng)中，常規(guī)跳頻通信通過同步字頭攜帶相關(guān)碼的方法來實(shí)現(xiàn)同步，但對于快跳頻來說，由于是一跳或者多跳傳輸一個調(diào)制符號，難以攜帶相關(guān)碼。對此引入雙跳頻圖案方法，提出了一種適用于快速跳頻通信系統(tǒng)的同步方案。采用短碼攜帶同步信息，克服了快速跳頻難以攜帶相關(guān)碼的困難。分析了同步性能，仿真結(jié)果表明該方案同步時間短、虛警概率低、捕獲概率高，同步性能可靠。
Abstract:
Synchronization is one of the key Techniques to frequency-hopping communication system， especially in the fast frequency hopping communication system. In conventional frequency hopping communication systems， synchronization can be achieved by synchronization-head which can be used to carry the synchronization information， but for the fast frequency hopping， Because modulation symbol is transmitted by per hop or multi-hop， it is difficult to carry the correlation code. For the limitation of fast frequency hopping in carrying correlation code， a fast frequency-hopping synchronization scheme with two hopping patterns is proposed. The synchronization information is carried by short code， which overcomes the difficulty of correlation code transmission in fast frequency-hopping. The performance of the scheme is analyzed， and simulation results show that the scheme has the advantages of shorter synchronization time， lower probability of false alarm， higher probability of capture and more reliable of synchronization.
標(biāo)簽：
快速跳頻
同步技術(shù)
通信系統(tǒng)
上傳時間：
2013-11-23
上傳用戶：mpquest
-
Single-Ended and Differential S-Parameters
Differential circuits have been important incommunication systems for many years. In the past,differential communication circuits operated at lowfrequencies, where they could be designed andanalyzed using lumped-element models andTechniques. With the frequency of operationincreasing beyond 1GHz, and above 1Gbps fordigital communications, this lumped-elementapproach is no longer valid, because the physicalsize of the circuit approaches the size of awavelength.Distributed models and analysis Techniques are nowused instead of lumped-element Techniques.Scattering parameters, or S-parameters, have beendeveloped for this purpose [1]. These S-parametersare defined for single-ended networks. S-parameterscan be used to describe differential networks, but astrict definition was not developed until Bockelmanand others addressed this issue [2]. Bockelman’swork also included a study on how to adapt single-ended S-parameters for use with differential circuits[2]. This adaptation, called “mixed-mode S-parameters,” addresses differential and common-mode operation, as well as the conversion betweenthe two modes of operation.This application note will explain the use of single-ended and mixed-mode S-parameters, and the basicconcepts of microwave measurement calibration.
標(biāo)簽：
差分電路
單端
模式
上傳時間：
2014-03-25
上傳用戶：yyyyyyyyyy
-
Agilent AN 154 S-Parameter Design Application Note S參數(shù)的設(shè)計與應(yīng)用
The need for new high-frequency, solid-state circuitdesign Techniques has been recognized both by microwaveengineers and circuit designers. These engineersare being asked to design solid state circuitsthat will operate at higher and higher frequencies.The development of microwave transistors andAgilent Technologies’ network analysis instrumentationsystems that permit complete network characterizationin the microwave frequency rangehave greatly assisted these engineers in their work.The Agilent Microwave Division’s lab staff hasdeveloped a high frequency circuit design seminarto assist their counterparts in R&D labs throughoutthe world. This seminar has been presentedin a number of locations in the United States andEurope.From the experience gained in presenting this originalseminar, we have developed a four-part videotape, S-Parameter Design Seminar. While the technologyof high frequency circuit design is everchanging, the concepts upon which this technologyhas been built are relatively invariant.The content of the S-Parameter Design Seminar isas follows:
標(biāo)簽：
S參數(shù)
上傳時間：
2013-12-19
上傳用戶：aa54
