`
`.I
`HANDBOOK of
`RADIO 8: WIRELESS
`TECHNOLOGY
`
`
`
`I\|\
`)SJtIII GibiliscoI
`
`‘A mm“
`
`Page 1 of 9
`
`APPLIED MATERIALS EXHIBIT 1013
`
`Page 1 of 9
`
`APPLIED MATERIALS EXHIBIT 1013
`
`
`
`Library of Congress Cataloging-in-Publication Data
`
`Gibiliscq Stan.
`Handbook of radio and wireless technology I Stan Gibilisco.
`p.
`cm.
`Includes index.
`ISBN 0-07-023024-2
`1. Radio. 2. Wireless communication systems.
`TK6550.G515
`1998
`621.382- dc21
`
`I. Title.
`
`98-8471
`CIP
`
`McGraw-Hill
`~
`A Division of The McGraw-Hill Companies
`
`Copyright © 1999 by The McGraw-Hill Companies, Inc. All rights
`reserved. Printed in the United States of America. Except as permitted
`under the United States Copyright Act of 1976, no part of this publication
`may be reproduced or distributed in any form or by any means, or stored
`in a data base or retrieval system, without the prior written permission of
`the publisher.
`
`1 2 3 4 5 6 7 8 9 0 DOC/ DOC 9 0 3 2 1 0 9 8
`
`ISBN 0-07-023024-2
`
`The sponsoring editor for this book was Scott Grillo, the editing supervisor was
`Stephen M Smith, and the production supervisor was Pamela A. Pelton. It was set
`in Vendome !CG by Joanne Morbit and Michele Zito of McGraw-HilJ's Hightstown,
`NJ, Professional Book Group composition unit.
`
`McGraw-Hill books are available at special quantity discounts to use as
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`For more information, please write to the Director of Special Sales,
`McGraw-Hill, 11 West 19th Street, New York, NY 10011. Or contact your
`local bookstore.
`
`,;;;:,,. This book is printed on recycled, acid-free paper containing
`
`\!Cl a minimum of 50% recycled de-inked fiber.
`
`Information contained in this work has _been obtained by The McGraw(cid:173)
`Hill Companies, Inc. ("McGraw-Hill") from sources believed to be reliable.
`However; neither McGraw-Hill nor its authors guarantee the accuracy or
`completeness of any information published herein and neither McGraw(cid:173)
`Hill nor its authors shall be responsible for any errors, omissions, or dam(cid:173)
`ages arising out of use of this information. This work is published with
`the understanding that McGraw-Hill and its authors are supplying infor(cid:173)
`mation, but are not attempting to render engineering or other professional
`services. If such services are required, the assistance of an appropriate pro(cid:173)
`fessional should be sought.
`
`\
`
`Page 2 of 9
`
`
`
`62
`
`Chapter 2
`
`will radiate. Parasitic arrays, such as the Yagi antenna and the quad
`antenna, operate on this principle.
`
`Selective Filters
`
`The term selective filter refers to circuits designed to tailor the way an
`electronic circuit or system responds to signals at various frequencies.
`There are many kinds of selective filters. Some are used at AF; others are
`used at RE
`
`Bandpass Filter
`
`Any resonant circuit, or combination of resonant circuits, designed to
`discriminate against all frequencies except a specific frequency ~' or a
`band of frequencies between two limiting frequencies ~ and ~' is called
`a bandpass filter. In a parallel LC circuit, a bandpass filter shows a high
`impedance at the desired frequency or frequencies, and a low imped(cid:173)
`ance at unwanted frequencies. In a series LC configuration, the filter has
`a low impedance at the desired frequency or frequencies, and a high
`impedance at unwanted frequencies. Figure 2-9A shows a simple parallel(cid:173)
`tuned LC bandpass filter; Fig. 2-9B shows a simple series-tuned LC band(cid:173)
`pass filter.
`Some bandpass filters are built with components other than actual
`coils and capacitors, but all such filters operate on the same principle.
`The crystal filter uses piezoelectric materials, usually quartz, to obtain a
`bandpass response. A mechanical filter uses vibration resonances of cer(cid:173)
`tain substances, usually ceramics. In optics, a simple color filte~ discrimi(cid:173)
`nating against all light wavelengths except within a certain range, is a
`form of bandpass filter.
`Bandpass filters are sometimes designed to have very sharg defined,
`resonant frequencies. Sometimes the resonance is spread out over a fairly
`wide range. The attenuation-versus-frequency characteristic of a bandpass fil(cid:173)
`ter is called the bandpass response. A bandpass filter can have a single,
`well-defined resonant frequency f
`, as shown in Fig. 2-9C, or the
`0
`response might be more or less rectangula~ having two well-defined
`limit frequencies f 0 and ~' as shown at D The bandwidth might be only
`a few hertz, such as with an audio filter designed for reception of Morse
`code. Or the bandwidth might be several megahertz, as in a helical filter
`
`_J
`
`Page 3 of 9
`
`
`
`Passive Electronic Components
`
`63
`
`Figure 2-9
`At A, elementary par(cid:173)
`allel-resonant band(cid:173)
`pass filter. At B,
`elementary series-res(cid:173)
`onant bandpass filter.
`At C, sharp bandpass
`response. At D,
`broad bandpass
`response.
`
`Input
`
`Output
`
`o---;_1;----0
`
`A.
`
`B.
`
`Frequency
`
`Frequency
`
`C.
`
`D.
`
`designed for the front end of a VHF or UHF radio receiver. A bandpass
`response is always characterized by high attenuation at all frequencies
`except within a particular range. The actual attenuation at desired fre(cid:173)
`quencies is called the insertion loss.
`
`Band-Rejection Filter
`
`A band-rejection filter; also called a band-stop filter; is a resonant circuit
`designed to pass energy at all frequencies, except within a certain
`, or
`range. The attenuation is greatest at the resonant frequency f 0
`between two limiting frequencies ~ and ff Figure 2-9E shows a simple
`parallel-resonant LC band-rejection filter; drawing F shows a simple
`series-resonant LC band-rejection filter. Note the similarity between
`band-rejection and bandpass filters. The fundamental difference is that
`
`Page 4 of 9
`
`
`
`64
`
`Figure 2-9 (cont.)
`At E, elementary
`parallel-resonant
`band-rejection filter.
`At F, elementary
`series-resonant band(cid:173)
`rejection filter. At G,
`sharp band-rejection
`response. At H,
`broad band-rejection
`response.
`
`Chapter 2
`
`Input
`
`Output
`
`Input
`
`Output
`
`o--;J;----o
`
`E.
`
`F.
`
`Frequency
`
`Frequency
`
`G
`
`H
`
`the band-rejection filter consists of parallel LC circuits connected in
`series with the signal path, or series LC circuits in parallel with the sig(cid:173)
`nal path; in bandpass filters, series-resonant circuits are connected in
`series, and parallel-resonance circuits in parallel.
`Band-rejection filters need not necessarily be made up of coils and
`capacitors, but they often are. Quartz crystals are sometimes used as
`band-rejection filters. Lengths of transmission line; either short-circuited
`or open, are useful as band-rejection filters at the higher radio frequen(cid:173)
`cies. A common example of a band-rejection filter is a parasitic suppressoI;
`used in high-power RF amplifiers.
`All band-rejection filters show an attenuation-versus-frequency charac(cid:173)
`teristic marked by low loss at all frequencies except within a prescribed
`range. Figure 2-9G and H shows two types of band-rejection response.
`A sharp response (at G) occurs at or near a single resonant frequency~- A
`
`Page 5 of 9
`
`
`
`passive Electronic Components
`
`65
`
`rectangular response is characterized by low attenuation below a limit ~
`and above a limit t;_, and high attenuation between these limiting fre(cid:173)
`quencies.
`
`Notch Filter
`
`A notch filter is a narrowband-rejection filter. Notch filters are found
`in many radio communications receivers. The notch filter is extremely
`convenient for reducing interference caused by strong, unmodulated car(cid:173)
`riers within the passband of a receiver.
`Notch-filter circuits are generally inserted in one of the intermediate(cid:173)
`frequency (IF) stages of a superheterodyne receive.i;. where the bandpass
`frequency is constant. There are several different kinds of notch-filter
`circuit. One of the simplest is a trap configuration, inserted in series
`with the signal path (see Fig. 2-9E). The notch frequency is adjustable; so
`that the deep null can be tuned to any frequency within the receiver
`passband.
`A properly designed notch filter can produce attenuation in excess of
`40 decibels (dB) in the center of the notch. Some sophisticated types,
`especially AF designs, can provide 60 dB of attenuation at the notch fre(cid:173)
`quency. Audio notch filters generally employ operational amplifiers
`with resistance-capacitance circuits. The frequency is adjusted by means
`of a potentiometer. In some AF notch filters, the notch width (sharpness)
`is adjustable.
`
`High-Pass Filter
`
`A high-pass filter is a combination of capacitance, inductance, and/or
`resistance; intended to produce large amounts of attenuation below a
`certain frequency and little or no attenuation above that frequency. The
`frequency at which the transition occurs is called the cutoff frequency At
`the cutoff frequency; the power attenuation is 3 dB with respect to the
`minimum attenuation. Above the cutoff frequency; the power attenua(cid:173)
`tion is less than 3 dB. Below the cutof£ the power attenuation is more
`than 3 dB.
`The simplest high-pass filter consists of a parallel inductor or a
`series capacitor. Generally; high-pass filters have a combination of par(cid:173)
`allel inductors and series capacitors, such as the simple circuits shown
`in Fig. 2-9I and J The filter at I is called an L-section high-pass filter;
`
`Page 6 of 9
`
`
`
`66
`
`Figure 2-9 (cont.)
`At I, L-section high(cid:173)
`pass filter. At J,
`T-section high-pass
`filter. At K, high-pass
`response.
`
`0---11---e----o
`
`Input
`
`Output
`
`Chapter 2
`
`Input
`
`I.
`
`J.
`
`Output
`
`Frequency
`
`K.
`
`that at J is called a T-section high-pass filter. These names are derived
`from the geometric shapes of the filters as they appear in schematic
`diagrams.
`Resistors are sometimes substituted for the inductors in a high-pass
`filter. This is especially true if active devices are used, in which case
`many filter sections can be cascaded.
`High-pass filters are used in a wide variety of situations in electronic
`apparatus. One common use for the high-pass filter is at the input of a
`television (TV) receiver. The cutoff frequency of such a filter is about 40
`MHz. The installation of such a filter reduces the susceptibility of the
`TV receiver to EMI from sources at lower frequencies.
`A high-pass response is an attenuation-versus-frequency curve that
`shows greater attenuation at lower frequencies than at higher frequen(cid:173)
`cies. The sharpness of the response can vary considerably. Usually; a
`high-pass response is characterized by a high degree of attenuation up
`to a certain frequency; where the attenuation rapidly decreases. Finally
`the attenuation levels off at near zero insertion loss. The cutoff frequen(cid:173)
`cy of a high-pass response is that frequency at which the insertion
`power loss is 3 dB with respect to the minimum loss. The ultimate attenu(cid:173)
`ation is the level of power attenuation well below the cutoff frequency;
`where the signal is virtually blocked. A good high-pass response is
`shown in Fig. 2-9K. The curve is smooth, and the insertion loss is essen(cid:173)
`tially zero everywhere well above the cutoff frequency.
`
`J
`
`Page 7 of 9
`
`
`
`Passive Electronic Components
`
`67
`
`Low-Pass Filter
`
`A low-pass filter is a combination of capacitance, inductance, and/or resis(cid:173)
`tance, intended to produce large amounts of attenuation above a certain
`frequency and little or no attenuation below that frequency. The frequen(cid:173)
`cy at which the transition occurs is called the cutoff frequency. At the
`cutoff frequency; the power attenuation is 3 dB with respect to the mini(cid:173)
`mum attenuation. Below the cutoff frequency; the power attenuation is
`less than 3 dB. Above the cutof( the power attenuation is more than 3 dB.
`The simplest low-pass filter consists of a series inductor or a parallel
`capacitor. More sophisticated low-pass filters have combinations of series
`inductors and parallel capacitors, such as the examples shown in Fig. 2-91
`and M. The filter at L is an L-section low-pass filter; the circuit at M is a
`pi-section low-pass filter. As above, these names are derived from the geo(cid:173)
`metric arrangement of the components as they appear in diagrams.
`Resistors are sometimes substituted for the inductors in a low-pass fil(cid:173)
`ter. This is especially true when active devices are used, in which case
`many filter stages can be cascaded. This substitution reduces the physical
`bulk of the circuit, and it saves money.
`Low-pass filters are used in many different applications in RF elec(cid:173)
`tronics. One common use of a low-pass filter is at the output of a high(cid:173)
`frequency (HF) transmitter. The cutoff frequency is about 40 MHz.
`When such a low-pass filter is installed in the transmission line between
`a transmitter and antenna, VHF harmonics are greatly attenuated. This
`
`Figure 2-9 (cont.)
`At L L-section low(cid:173)
`pass filter. At M,
`pi-section low-pass
`filter. At N. low-pass
`response.
`
`lOOOOOr°
`
`Output
`
`Output
`
`Input
`
`,+I
`
`M.
`
`Frequency
`
`N.
`
`Page 8 of 9
`
`
`
`68
`
`Chapter 2
`
`reduces the probability of EMI to TV receivers using outdoor antennas.
`In a narrowband transmitter, a low-pass filter might be built in for
`reduction of harmonic output.
`A low-pass response is an attenuation-versus-frequency curve that shows
`greater attenuation at higher frequencies than at lower frequencies. The
`sharpness of the response can vary considerably. UsuallYt a low-pass
`response is characterized by a low degree of attenuation up to a certain
`frequency; above that point, the attenuation rapidly increases. Finally
`the attenuation levels off at a large value. Below the cutoff frequencYt the
`attenuation is practically zero.
`The cutoff frequency of a low-pass response is that frequency at which
`the insertion power loss is 3 dB with respect to the minimum loss. The
`ultimate attenuation is the level of attenuation well above the cutoff fre(cid:173)
`quencYt where the signal is virtually blocked. A good low-pass response
`looks like the attenuation-versus-frequency curve shown in Fig. 2-9N.
`The curve is smooth, and the insertion loss is essentially zero every(cid:173)
`where well below the cutoff frequency.
`
`Diodes
`
`The term diode means "two elements." Almost all diodes are made from
`silicon or other semiconducting materials.
`
`Theory of Operation
`
`When P-type semiconductor and N-type semiconductor materials are joined,
`a P-N junction is the result. Such a junction has properties that make
`semiconductor materials useful as electronic devices. A diode is formed
`by a single P-N junction. The N-type material comprises the cathode, and
`the P-type material forms the anode.
`In a diode, electrons flow in the direction opposite the arrow in the
`schematic symbol. (Physicists consider current to flow from positive to
`negative, and this is in the same direction as the arrow points.) Current
`will not normally flow the other way unless the voltage is very high. If
`you connect a battery and a resistor in series with a P-N junction, cur(cid:173)
`rent will flow if the negative terminal of the battery is connected to the
`N-type material (cathode) and the positive terminal is connected to the
`P-type material (anode). No current will flow if the battery is reversed.
`
`J
`
`Page 9 of 9
`
`