Quantcast TIME-DOMAIN REFLECTOMETRY

Share on Google+Share on FacebookShare on LinkedInShare on TwitterShare on DiggShare on Stumble Upon
Custom Search
 
  
 
5-24 Q-7. When referring to spectrum analyzers, what is meant by the term resolving signals? TIME-DOMAIN REFLECTOMETRY TIME-DOMAIN REFLECTOMETRY is a testing and measurement technique that has found increasing usefulness in testing transmission lines (both metallic and fiber-optic), cables, strip lines, connectors, and other wideband systems or components. Basically, time-domain reflectometry is an extension of an earlier technique in which reflections from an electrical pulse were monitored to locate faults and to determine the characteristics of power transmission lines. You can compare time-domain reflectometry to a closed-loop radar system in which the transmitted signal, a very fast step pulse, is fed into the system and the reflections resulting from discontinuities or impedance deviations in the system are monitored on a crt. The technique used in time-domain reflectometry consists of feeding an impulse of energy into the system and then observing that energy as it is reflected by the system at the point of insertion. When the fast-rise input pulse meets with a discontinuity or impedance mismatch, the resultant reflections appearing at the feed point are compared in phase, time, and amplitude with the original pulse. By analyzing the magnitude, deviation, and shape of the reflected waveform, you can determine the nature of the impedance variation in the transmission system. Also, since distance is related to time and the amplitude of the reflected step is directly related to impedance, the comparison indicates the distance to the fault as well as the nature of the fault. Figure 5-25, view A, view B, view C, and view D, illustrates typical transmission line problems that can easily be identified by using a time-domain reflectometer (tdr). In addition to showing both the distance to and the nature (resistive, inductive, or capacitive) of each line discontinuity, time-domain reflectometry also reveals the characteristic impedance of the line and indicates whether losses are shunt or series. They are also used to locate and analyze connectors and splices. Figure 5-25A.—Time-domain reflectometer display of transmission line problems.


Electrical News
Robots Confront Safety Standards
An emerging crop of industrial robots will be more user-friendly...
eetimes.com
Electronic Brain by 2023
Progress continues on fake brain to be used as test...
eetimes.com
Google, Silicon Labs Mesh for ZigBee-Like Protocol
Google's Nest-led Thread Group is meeting at its campus in...
eetimes.com
Bionic Ear Due Soon
STMicroelectronics collaborates with two companies on a bionic ear that...
eetimes.com
Peek Into BMW's Ultimate Driving Museum
BMW Welt and BMW Museum, located next to BMW headquarters...
eetimes.com
New Common Parts Library Supports Connected Device Design
Online sourcing site Octopart inaugurates a Common Parts Library (CPL)...
eetimes.com
Altera Announces Non-Volatile MAX 10 FPGAs & Eval Kits
MAX 10 FPGAs are of interest for a broad range...
eetimes.com
LPDDR3 Is A Half-Step
The rapid evolution of smartphones drove the quick adoption of...
eetimes.com
IBM Conquers Wafer-Scale Graphene
IBM has found a way to vastly reduce the costs...
eetimes.com
Telecom Capex to Fall 2% in 2015
Telecom carriers are expected to shave their capital spending on...
eetimes.com
EEVblog #668 – Mailbag + FLIR TG165
Help beat Congenital Muscular Dystrophy (Pozible campaign live tomorrow) A...
eevblog.com
Sensors Build Case Against Cold
Heat Seek, grand prize winner of this year's NYC BigApps...
eetimes.com
Let's Talk About Open-Source Hardware
Although the meaning of open source in software is quite...
eetimes.com
DDR Memory Testing: Best-Practices
The strict control of clock and data timing leaves little...
eetimes.com
The Other Tesla
This Indiegogo fundraiser is for a Tesla museum in his...
eetimes.com
The Zen of Spin
The concept of spin is ground-zero in relativistic quantum mechanics...
eetimes.com
Do Results Matter?
Sometimes you have to look past your enthusiasm for developing...
eetimes.com
IoT Calls for Simpler Protocol
Chirp is a simplified messaging scheme geared for the Internet...
eetimes.com
HP Ships First ARM Servers
Hewlett-Packard is shipping its first mainstream commercial servers using the...
eetimes.com
 


Privacy Statement - Copyright Information. - Contact Us

comments powered by Disqus

Integrated Publishing, Inc.
9438 US Hwy 19N #311 Port Richey, FL 34668

Phone For Parts Inquiries: (727) 755-3260
Google +