The File - Nov 16, 2008 - (Page 1)

India’s fortnightly focus on electronics design November 16-30, 2008 Data acquisition shuns wires By John Hanks Vice President Data Acquisition and Control National Instruments Corp. lect more data for added insight into their manufacturing, control or processing applications. Adoption challenges Despite the many advantages of wireless technology for data ac- Wireless technology is revolutionising the way the world collects and shares information, from mobile phones to Wi-Fi hotspots. The data acquisition space is no exception. Increasingly, scientists and engineers are facing pressures to take their measurements outside the lab. Wireless technology enables scientists and engineers to take measurements where cabling has been impractical. Additionally, wireless technology is saving engineers money. Wireless measurements have less installation and maintenance overhead than cabled infrastructure. Because of this, engineers can col- Hanks: In data acquisition, you can leverage IEEE 02.11g for high bandwidth measurements and WPA2 for the highest security. quisition, the industry has been slow to adopt the technology. There are several possible reasons for this, but the three most important are ease-of-use, security and integration with existing measurement systems. The fundamental problem with many of today’s wireless sensor solutions is that they are primarily technology-driven versus marketor need-driven. Domain experts are not necessarily interested in the technological means by which they get their data. They are more concerned with the accuracy and reliability of their measurements, and they typically do not have the time or the skill-set to set up a new wireless network infrastructure. Using existing network infrastructure, however, can be complicated by security concerns. Many facilities have stringent guidelines on what is appropriate to broadcast through the air or share over a network. As more measurement and control applications tie into the business backend, they fall under the domain of an IT organisation, whose expertise is in network security and reliability, not measurements. Security is particularly important in confidential plant operations or in government or military applications. Many wireless sensor solutions today do not offer any means of security beyond the secrecy of their own proprietary transmission protocol, and most of these, unfortunately, are relatively insecure when compared with modern cryptographic algorithms. Finally, getting a complete wireless measurement solution from one vendor is difficult. The wireless continued on page Function gens simplify measurement Naresh Narasimhan Country Marketing Manager Tektronix, Inc. Inside In Focus 4 6 7 Embedded system eases rail maintenance Working with IT for networked DAQ Digital telemetry advances torque measurement A number of electronic design applications require stimuli with amplitudes that exceed the capabilities of most arbitrary/function generators available in the market today. These applications include power semiconductors, such as MOSFETs and IGBTs widely used in automotive electronic systems and switching power supplies, amplifiers for gas chromatography and mass spectroscopy detectors, and others in science and industry. Commonly, arbitrary/function generators provide amplitudes of up to 10Vpp into 50 Ω loads and 20Vpp into open circuits. The devices just mentioned often operate over an input range that is twice as large. Until now, testing these devices over their full operating range commonly required an amplifier to boost the signal provided by a standard generator. This increased the complexity of the test set-up, created uncertainty about the effective amplitude at the amplifier output, and added equipment cost. Conventional approach In a typical measurement set-up of a standard arbitrary/function generator with additional amplifier to boost the amplitude to the required level, the generator output is connected to the amplifier input (figure 1). Some amplifiers allow the inputs and/or outputs to continued on page Events 11 BIG Expo 2008, Broadband Tech 2008, Wind India 2008, National Conference On E-Governance, ICSST, NGSA - 08 Sponsors 2 5 Farnell National Semiconductor www.eetindia.com http://www.eetindia.co.in/SEARCH/SUMMARY/technical-articles/Wi~%40~Fi.HTM?ClickFromNewsletter_081116 http://www.eetindia.co.in/SEARCH/SUMMARY/technical-articles/wireless sensor.HTM?ClickFromNewsletter_081116 http://www.eetindia.co.in/SEARCH/SUMMARY/technical-articles/RELEVANCE/data acquisition.HTM?ClickFromNewsletter_081116 http://www.powerdesignindia.co.in/SEARCH/SUMMARY/technical-articles/MOSFET.HTM?ClickFromNewsletter_081116 http://www.powerdesignindia.co.in/SEARCH/SUMMARY/technical-articles/IGBT.HTM?ClickFromNewsletter_081116 http://www.eetindia.com/STATIC/REDIRECT/Newsletter_081116_GS01.htm http://www.eetindia.co.in/

Table of Contents for the Digital Edition of The File - Nov 16, 2008

EETimes India - November 16, 2008
Contents
Farnell
Embedded System Eases Rail Maintenance
National Semiconductor
Working With IT for Networked DAQ
Digital Telemetry Advances Torque Measurement
Events

The File - Nov 16, 2008