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1、P1: JDW JWBS032-01JWBS032-KarmakarJuly 24, 20109:57Printer Name: Yet to Come PART I INTRODUCTION TO RFID P1: JDW JWBS032-01JWBS032-KarmakarJuly 24, 20109:57Printer Name: Yet to Come CHAPTER 1 THE EVOLUTION OF RFID BEHNAM JAMALI School of Electrical and Electronic Engineering, University of Adelaide,
2、 Adelaide, Australia 1.1INTRODUCTION Radio-frequency identifi cation (RFID) is a relatively new technology. Some believe that its concept might have originated in military plane identifi cation during World War II and that it really started to be intensively developed for tracking and access applica
3、tions during the 1980s. These wireless systems allow for noncontact and non- line-of-sight reading of data from electronic labels by the means of electromagnetic signals, and consequently they are attractive for numerous tracking and tagging scenarios.Forexample,theyareeffectiveinhostileenvironments
4、suchasmanufacture halls, where bar code labels could not survive. Furthermore, RFID tags can be read in challenging circumstances when there is no physical contact or direct line of sight. RFID has established itself in a wide range of markets, including livestock identifi cation and automated vehic
5、le identifi cation systems, because of its ability to track moving objects. RFID technology is becoming a primary player in automated data collection, identifi cation, and analysis systems worldwide. RFID, its application, its standardization, and its innovation are constantly chang- ing. It is a ne
6、w and complex technology that is not well known and well understood by the general public, or even by many practitioners. Many areas of RFID operation need development to achieve a longer reading range, larger memory capacity, faster signal processing, and more secure data transmission. 1.2ELECTROMA
7、GNETIC TIMELINE In this section we will provide an anecdotal history of the most important electro- magnetic personalities in chronological order. A short biography of each scientist is also provided along with their main contribution to this fi eld Handbook of Smart Antennas for RFID Systems, Edite
8、d by Nemai Chandra Karmakar CopyrightC?2010 John Wiley and having systematically studied the fi nancial markets and invested accordingly, he died a very wealthy man. Gauss law of electrostatics states that the P1: JDW JWBS032-01JWBS032-KarmakarJuly 24, 20109:57Printer Name: Yet to Come ELECTROMAGNET
9、IC TIMELINE5 TABLE 1.1. Maxwells Equation Gauss law of electrostatics E = Gauss law of magnetism B = 0 Faradays law of induction E = dB dt Amperes law with Maxwells displacement current B = 0J + 00 dE dt total electric fl ux through a closed surface is proportional to the total electric charge enclo
10、sed within the surface: ? s 0E ds = ? v dv(1.4) Michael Faraday (17911867) was born in a village near London. Faraday be- came the greatest experimentalist in electricity and magnetism of the nineteenth century. He produced an apparatus that was the fi rst electric motor, and in 1831 he succeeded in
11、 showing that a magnet could induce electricity. Faradays law of induction describes an important basic law of electromagnetism: E = d dt (1.5) James Clerk Maxwell (18311879) is ranked with Newton and Einstein for the fundamental nature of his many contributions to physics. Most importantly, he orig
12、inated the concept of electromagnetic radiation, and his fi eld equations (1873) ledtoEinsteinsspecialtheoryofrelativity.Inclassicalelectromagnetism,Maxwells equations are a set of four partial differential equations that describe the properties of the electric and magnetic fi elds and relate them t
13、o their sources, charge density, and current density. Maxwell used the equations listed in Table 1.1 to show that light is an electromagnetic wave. Heinrich Rudolf Hertz (18471894), a German physicist, was the fi rst to broad- cast and receive radio signals. He applied Maxwells theories to the produ
14、ction and reception of radio waves. In 1884, He rederived the Maxwells equations by a new method, casting them in modern form as shown in Table 1.1. He produced electro- magnetic waves in the laboratory and measured their wavelength and velocity. He showed that the nature of their refl ection and re
15、fraction was the same as those of light, confi rming that light waves are electromagnetic radiation obeying Maxwells equations. Guglielmo Marconi (18741937), an Italian physicist, is the inventor of radio. He was granted a patent for a successful system of radio telegraphy in 1896. In 1909 he receiv
16、ed the Nobel Prize in Physics. Marconis great triumph was in 1901, when he successfully received radio signals transmitted across the Atlantic Ocean. This sensationalachievementwasthestartofthevastdevelopmentofradiocommunication and broadcasting the way we know it today. P1: JDW JWBS032-01JWBS032-KarmakarJuly 24, 20109:57Printer Name: Yet to Come 6THE EVOLUTION OF RFID 1.3RADAR The use of electromagnetic waves to identify the range, altitude, direction
