DOCSLIB.ORG

ECE 373 Fundamentals of Communication Lecture-15 Phase

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
ECE 373 Fundamentals of Communication Lecture-15 Phase ECE 373 Fundamentals of Communication Lecture-15 Phase Modulation For the modulating signal, i.e., message signal, 푚(푡), the phase modulated (PM) is obtained as 푠(푡) = 퐴푐 cos (2휋푓푐푡 + 푘푝푚(푡)) Frequency Modulation For the modulating signal, i.e., message signal, 푚(푡), the frequency modulated (FM) is obtained as 푡 푠(푡) = 퐴푐 cos (2휋푓푐푡 + 2휋푘푓 ∫ 푚(푡)푑푡) 0 Narrowband and Wideband FM For message signal 푚(푡), narrowband FM is generated as 푠(푡) = 퐴푐 cos(2휋푓푐푡) − 퐴푐휃(푡) sin(2휋푓푐푡) 푡 휃(푡) = 2휋푘푓 ∫ 푚(푡)푑푡 0 For narrowband modulated signals we have Δ푓 훽 = ≪ 1 푊푚 and for wideband modulated signals we have Δ푓 훽 = > 1. 푊푚 For the message signal 푚(푡) having bandwidth 푊푚, the bandwidth of the narrowband modulated signal 푠푁퐵퐹푀(푡) equals to 2푊푚. 1 Case Study: The bandwidth of FM modulated signal for sinusoidal message signal For the message signal 푚(푡) = 퐴 cos(2휋푓푚푡). FM modulated signal is calculated using the formula 푡 푠(푡) = 퐴푐 cos (2휋푓푐푡 + 2휋푘푓 ∫ 푚(푡)푑푡) # 0 as 푠(푡) = 퐴푐 cos(2휋푓푐푡 + 훽 sin(2휋푓푚푡)) (1) where 훽퐹 is the modulation index defined as Δ푓 퐴푘푓 훽 = → 훽 = . 푊푚 푓푚 The Fourier transform of (1) can be calculated as ∞ 퐴 푆(푓) = 푐 ∑ 퐽 (훽) [훿(푓 − [푓 + 푛푓 ]) + 훿(푓 + [푓 + 푛푓 ])]. (2) 2 푛 푐 푚 푐 푚 푛=−∞ The graph of 푆(푓) consists of impulses at locations 푓 = 푓푐 + 푛푓푚 2 The spectrum expression ∞ 퐴 푆(푓) = 푐 ∑ 퐽 (훽) [훿(푓 − [푓 + 푛푓 ]) + 훿(푓 + [푓 + 푛푓 ])] 2 푛 푐 푚 푐 푚 푛=−∞ Can be plotted as in Figure-1 to 3. 3 Figure-1 4 5 Figure-2 Figure-3 Carrier frequency is 푓푐 = 200퐻푧 푓푚 = 12퐻푧 6 The graph of Bessel function 퐽푛(훽) is depicted in Figure-4. Figure-4 The graph of Bessel function 퐽푛(훽) Properties of the Bessel function 푱풏(휷) 7 To determine the bandwidth of the modulated signal, we can limit the summation limits of the expression ∞ 퐴 푆(푓) = 푐 ∑ 퐽 (훽) [훿(푓 − [푓 + 푛푓 ]) + 훿(푓 + [푓 + 푛푓 ])] 2 푛 푐 푚 푐 푚 푛=−∞ as in 푁 퐴 푆 (푓) = 푐 ∑ 퐽 (훽) [훿(푓 − [푓 + 푛푓 ]) + 훿(푓 + [푓 + 푛푓 ])] 푁 2 푛 푐 푚 푐 푚 푛=−푁 where 푁 value is determined considering modulation index value 훽 as in 푁 2 2 퐽0 (훽) + 2 ∑ 퐽푛(훽) ≥ 0.99. 푛=1 And the bandwidth of the modulated signal is determined as 2푁푓푚. Example: The signal 푚(푡) = 10푐표푠(2휋 × 400푡) is to be transmitted using FM techniques. Find the practical bandwidth for 푘푓 = 200 퐻푧/푉. Solution: The modulation index is calculated as 푘푓퐴푚 10 × 200 훽 = → 훽 = → 훽 = 5. 푓푚 400 The equation 푁 2 2 퐽0 (훽) + 2 ∑ 퐽푛(훽) ≥ 0.99 푛=1 can be solved using Table 1 for 푁 considering the calculated 훽 = 5 as 푁 = 6 and the bandwidth of the modulated signal is calculated as 푊푠 = 2푁푓푚 → 푊푠 = 12 × 400 → 푊푠 = 4800퐻푧. 8 Table 1 Values of 푱풏(휷) Radio Broadcast Here are some of the major applications for AM and FM Figure 5 9 Figure 6 The electromagnetic spectrum. Figure 6 The electromagnetic spectrum used in electronic communication. 10 AM Broadcasting Figure 7 Frequency spectrum of AM broadcast band. An AM broadcast station has a total bandwidth of 10 kHz. In addition, AM broadcast stations are spaced every 10 kHz across the spectrum from 540 to 1600 kHz. This is illustrated in Figure 7. The sidebands from the first AM broadcast frequency extend down to 535 kHz and up to 545 kHz, forming a 10-kHz channel for the signal. The highest channel frequency is 1600 kHz, with sidebands extending from 1595 up to 1605 kHz. There are a total of 107 10-kHz-wide channels for AM radio stations. FM Broadcasting For AM: 10kHz bandwidth from 540-1600 kHz for 107 possible bands. For FM: 200 kHz bandwidth from 88.1-108.1 MHz from 100 possible bands. 11 Figure 8 The FM radio broadcast band is allocated the frequency spectrum from 88 to 108 MHz. There are 100 channels spaced 200 kHz apart. The first channel center frequency is 88.1 MHz; the last, or 100th, channel center frequency is 107.9 MHz. The channel center frequencies are centered as 88.1, 88.3, 88.5, 88.7, ⋯ ⋯ , 107.7, 107.9. Each 200-kHz channel has a 150-kHz modulation bandwidth with 25-kHz “guard bands” on either side of it. The FM broadcast band permits a maximum deviation of ±75 kHz and a maximum modulating frequency of 15 kHz. Note: FM radio was assigned the 42–50 MHz band of the spectrum in 1940. In 1945, the FCC (Federal Communications Commission | The United States) moved FM to 88–108 MHz, obsoleting all existing receivers. 12 .
Load more

Recommended publications
  • Radio Wave Spectrum Allocations and Dial Markings on Old Radios – Page 1
    Radio Wave Spectrum Allocations and Dial Markings on Old Radios – page 1 When you look at the dial of an old radio you may be confused by the numbers and letters written on the dial. In Australia and New Zealand the dials of Medium Wave radios (often called the Broadcast Band) were usually marked with the station call signs. In Australia, if the dial scale was quite small, a radio would only have the stations in that state marked on the dial. Some radios also had the Frequency and/or the Wave Length marked but this was not common throught period from 1936 to the end of the Australian made radios. Medium Wave Broadcast Band This is the band we tune to when we listen to an AM radio and most countries use frequency allocations between 526.5KHz and 1705KHz. Not all countries use all this allocation. Stereo transmission is possible and has been offered by some stations in the U.S., Canada, Mexico, the Dominican Republic, Paraguay, Australia, The Philippines, Japan, South Korea, South Africa, and France. However, there are multiple standards for AM stereo with C-QUAM being the most common in the United States as well as other countries, and receivers that implement the technologies are relatively rare. The FM Broadcast Band This is the range of frequencies we tune to when we tune a modern FM radio receiver. The international frequency allocation for this band is now 87.5MHz to 108MHz. This is often referred to as the CCIR Band. Over the years some countries have used other frequencies for this band and you will see these on the dials of some old FM radios you may find from time to time.
    [Show full text]
  • Guidelines for FM Broadcast Standards
    TECHNICAL GUIDELINES FOR FM BROADCAST STANDARDS Directorate of Technical Regulations February 2014 94, Kairaba Avenue, P. O. Box 4230 Bakau, The Gambia Tel. (220) 4399601 / 4399606 Fax: (220) 4399905 EMail: [email protected] Website: www.pura.gm Contents 1. DEFINITIONS ........................................................................................................................... 2 2. INTRODUCTION ...................................................................................................................... 3 3. CLASSES OF FM BROADCAST STATIONS ........................................................................ 3 3.1 Public/Commercial FM station .................................................................................................. 3 3.2 Community Fm Stations ............................................................................................................. 3 3.3 Educational/Scientific FM station [Non Commercial] ............................................................... 3 4. FREQUENCY SPACING .......................................................................................................... 3 5. TECHNICAL REQUIREMENTS ............................................................................................. 4 5.1 Safety Requirements ................................................................................................................... 4 5.2 Transmitting Facilities ...............................................................................................................
    [Show full text]
  • Digital Radio Power Increase
    Before the FEDERAL COMMUNICATIONS COMMISSION Washington, D.C. 20554 In the Matter of ) ) Digital Audio Broadcasting Systems ) MM Docket No. 99-325 And Their Impact On the Terrestrial Radio ) Broadcast Service ) ) COMMENTS OF THE NATIONAL ASSOCIATION OF BROADCASTERS The National Association of Broadcasters (NAB)1 hereby responds to the Public Notice2 soliciting public comment on recent filings in the digital audio broadcasting proceeding. By this Notice, the Media Bureau of the Federal Communications Commission (FCC) is seeking comment on three filings: a request by 18 radio broadcasters and the four largest manufacturers of broadcast transmission equipment (Joint Parties) to permit a voluntary increase in digital power for FM digital broadcasters, up to a maximum of 10 percent of a station’s authorized analog power;3 a technical report by iBiquity Digital Corporation (iBiquity) examining the benefits of this proposed increase in digital power, the compatibility with analog broadcasting and the potential interference effects 1 The National Association of Broadcasters is a trade association that advocates on behalf of more than 8,300 free, local radio and television stations and also broadcast networks before Congress, the Federal Communications Commission and the Courts. 2 Public Notice, DA 08-2340, MM Docket No. 99-325, October 23, 2008. 3 Joint Parties Ex Parte letter, filed in MM Docket No. 99-325, June 10, 2008 (Joint Parties request). resulting from the proposed increase;4 and a study by National Public Radio (NPR) on Corporation for Public Broadcasting-supported research on digital radio coverage and interference.5 As discussed below, the benefits of permitting FM broadcasters to optionally increase the power in their digital signal are compelling.
    [Show full text]
  • Shortwave-Listening
    Listen to global news in the making! Monitor transmissions from Voice of America. Radio Canada, Radio Netherlands. Radio Moscow and many others. Learn how radio waves tra- vel. Get information on popular shortwave bands and licensing for a Itypes of equipment. Radio Listener's Guide by William Barden, Jr. Radio Shack A Division of Tandy Corporation First Edition First Printing-1987 Copyright01987 by William Barden Jr., Inc. Printed in the United States of America. All rights reserved. Reproduction or use, without express permission, of editorial or pictorial content, in any manner, is prohibited. No patent liability is assumed with respect to the use of the information contained herein. Library of Congress Catalog Card Number: XX-XXXXX Radio Listener's Guide T Table of Contents Section I World of the BBC, Radio Moscow, Police Calls, Aircraft Communications, and Hams Chapter 1. Radio—What Is It' Generating Radio Waves—The Radio Spectrum—Radio Equipment and Frequencies—Band Use—How Radio Waves Travel—Radio Licenses and Listening—Subbands and Channels—Radio Equipment Chapter 2. Types of Broadcasting Voice Communication—Code Transmission—Teleprinter Transmission— Facsimile Transmission—Slow-Scan Television—Fast-Scan Television — Repeaters— Portable Phones—Satellite Reception—Transmitting Power Chapter 3. Shortwave Broadcasters Frequency Assignments—The European Long-Wave Band—The AM Broadcast Band—Tropical Broadcasting-49- and 41-Meter Bands-31- and 25-Meter Bands—Above the 25-Meter Band—A Typical Listening Session—Logging Foreign Stations—Foreign Broadcast lnformation—QSL Cards Chapter 4. Other Types of Broadcasting in the Lower Frequencies Transmissions Below the AM Broadcast Band—The AM Broadcast Band— Portable Phones—Marine Transmissions—CW Transmissions—Radio Teleprinter—Single Sideband—Time and Frequency Signals—Weather Maps by Facsimile—Citizen's Band Frequencies—The Russian Woodpecker—Pirate and Clandestine Stations Chapter 5.
    [Show full text]
  • Kidsdictionary.Pdf
    Access Charges: This is a fee charged by local phone companies for use of their networks. Amplitude Modulation (AM) that's the "AM" Band on your Radio: A signaling method that varies the amplitude of the carrier frequencies to send information. The carrier frequency would be like 910 (kHz) AM on your AM dial. Your radio antenna receives this signal and then decodes it and plays the song. Analog Signal: A signaling method that modifies the frequency by amplifying the strength of the signal or varying the frequency of a radio transmission to convey information. Bandwidth The amount of data passing through a connection over a given time. It is usually measured in bps (bits-per- second) or Mbps. Broadband Broadband refers to telecommunication in which a wide band of frequencies is available to transmit information. More services can be provided through broadband in the same way as more lanes on a highway allow more cars to travel on it at the same time. Broadcast To transmit (a radio or television program) for public or general use. In other words, send out or communicate, especially by radio or television. Cable A strong, large-diameter, heavy steel or fiber rope. The word history of cable derives from Middle English, from Old North French, from Late Latin capulum, lasso, from Latin capere, meaning to seize. Calling Party Pays A billing method in which a wireless phone caller pays only for making calls and not for receiving them. The standard American billing system requires wireless phone customers to pay for all calls made and received on a wireless phone.
    [Show full text]
  • 750 Review Insert
    The Eton Elite 750 is much more than just a fancy-looking boom-box shortwave receiver, reports WB6NOA, who listened to all it has to offer, including longwave, shortwave, the AM and FM broadcast bands, and the VHF air band. CQ Reviews: Eton Elite 750 Shortwave Receiver BY GORDON WEST,* WB6NOA s ham operators, we know not to pre-judge a radio by just how it Alooks, or how many buttons and meters it may have on the face. Like many of you, I have a collection of no- name bargain mail-order portable shortwave (SW) receivers, but few can hold a candle to those from name-brand manufacturers. Now, this monster- sized Eton receiver is hitting the mar- ket in grand style. The Eton Elite 750 is major-sized multi-mode receiver, fun for a radio enthusiast wanting to tune in what’s out there from 100 kHz to 30 MHz, plus the AM and FM broadcast bands and AM air-band reception. The Eton name may be unfamiliar to you, and the 750 looks a lot like a pre- vious radio from Grundig. Actually, the two companies have a relationship that spans 35 years, as explained by Eton CEO and Chairman Esmail Amid- The large speaker makes the Eton Elite 750 a great poolside or beach enter- Hozour. “From our initial partnership tainment radio, too! Plenty of audio output, enough to also power a personal with Max Grundig in 1979, Eton has car- music player that can plug in. ried on Grundig’s 75+ year legacy in developing the best-in-class world band we bring new and exciting shortwave non-directional radio beacons (NDBs), radios.” Esmail continued, “Eton’s dedi- products to the market each year.” Navtex, 630-meter ham radio CW bea- cation to design and innovation spans cons, and various government stations partnerships with Drake to ensure high- Exploring the Elite 750 lurking down here.
    [Show full text]
  • Audio Level Equalization of Television Sound, Broadcast FM and National Weather Service FM Radio Signals
    Europaisches Patentamt European Patent Office © Publication number: 0 512 374 A1 Office europeen des brevets EUROPEAN PATENT APPLICATION © Application number: 92107242.7 int. CI 5= H04N 5/60, H04B 1/16 @ Date of filing: 28.04.92 © Priority: 06.05.91 US 695803 F-92400 Courbevoie(FR) @ Date of publication of application: @ Inventor: Kim, Yong Hyun 11.11.92 Bulletin 92/46 Blk 127, Pasir Ris St.11, 04-395 Singapore 1851(SG) © Designated Contracting States: DE FR GB IT 0 Representative: Einsel, Robert, Dipl.-lng. © Applicant: THOMSON CONSUMER Deutsche Thomson-Brandt GmbH Patent- ELECTRONICS S.A. und Lizenzabteilung Gottinger Chaussee 76 9, Place des Vosges, La Defense 5 W-3000 Hannover 91 (DE) © Audio level equalization of television sound, broadcast FM and national weather service FM radio signals. © A television receiver includes a single tuner (102) for tuning both television channels and broadcast FM stations. The tuner (102) serves as the first conversion stage of a double conversion FM receiver, a separate mixer-oscillator (180) converts the FM radio sound IF to 4.5 MHz for processing in the television receiver's sound channel. A single discriminator circuit (130) is employed for tuning FM radio signals having a first deviation, such as broadcast FM radio signals, and FM signals having a second deviation (i.e., the television sound signals), and FM radio signals having a third deviation, such as signals of an information service, such as in the United States, the National Weather Service. Circuitry (136,137) for amplifying the output signal of the discriminator circuit exhibits a first gain, and a first volume control range when amplifying FM signals having the first deviation, exhibits a second gain and the first volume control range, when amplifying FM signals having the second deviation, and exhibits a second gain, and a second volume control range when amplifying FM signals having the third deviation.
    [Show full text]
  • I Would to Thank the Commission for Issuing This Notice of Proposed
    Before the Federal Communications Commission Washington, D.C. 20554 In the matter of ) ) Revitalization of the AM Radio Service ) MB Docket No. 13-249 To: The Commission COMMENT BY BRIAN J. HENRY I hold a Lifetime FCC General Class Radiotelephone license as well as an Amateur Advanced Class license and have been a broadcast engineer since the late 1970’s. I have constructed, repaired, and maintained countless AM broadcast stations over the course of my career and I am a former AM broadcast station licensee (KLLK-Willits, California). I am the proprietor of Henry Communications, a company that I founded in 1978, to provide technical services to the radio and television broadcast industry. I currently do not have an interest in any broadcast property. I am participating in this proceeding because I am passionate about AM broadcasting and I want to help revitalize it. I. Introduction I would like to thank The Commission for issuing this Notice of Proposed Rulemaking as it attempts to mitigate some of its concerns regarding the long-term viability of the AM broadcast band. The AM broadcast industry needs your help and guidance. Every ten years or so “AM Improvement” becomes a priority in the broadcast industry. It is always the same. There needs to be further deregulation. I would like to suggest that deregulation has gone far enough and that a certain amount of re-regulation and stricter enforcement of the existing laws could be helpful in the effort to revitalize AM. I am concerned that the proposals that The Commission is considering may ultimately result in a degradation of AM quality and will not be an enhancement to the service.
    [Show full text]
  • 1 Before the Federal Communications Commission Washington, D.C
    Before the Federal Communications Commission Washington, D.C. 20554 In the Matter of RM No. 9395 Amendment of Part 73 of the Commission's Rules to Permit the Introduction of Digital Audio Broadcasting in the AM and FM Broadcast Services ) GROUP COMMENTS FILED ON BEHALF OF THE ORGANIZATIONS AND INDIVIDUALS LISTED BELOW. IDENTIFICATION OF PARTIES My name is Ted M. Coopman and I am a resident of Santa Cruz, CA. I have a Master of Science in Mass Communications from San Jose State University (1995) and have been researching broadcasting since 1993. I have presented numerous papers on this subject at professional conventions held by the National Communication Association, the American Communication Association, the Western Communication Association, and the Southern States Communication Association. I have also had a manuscript published in the Journal of Broadcasting and Electronic Media (Vol. 43, No. 4, Fall 1999) and operate a website(www.roguecom.com/rogueradio) where I house my research on broadcasting. I am also the co-founder of Rogue Communications, a multi-service consulting and research company. In these capacities, I have become concerned with the state of radio broadcasting in the United States. Our current free radio service is threatened by media consolidation, the loss of diversity, localism, and the increased use of FM spectrum for ancillary services to the detriment of music and voice broadcasting. I have drafted his Group Comment to present the most basic issues and needs expressed by a diverse cross- section of individuals and organizations concerned with the health of radio. We, the undersigned organizations and individuals, representative of a wide spectrum of advocates for a democratic, community service oriented, free AM-FM broadcast service, strongly believe that the NPRM concerning the adoption of In Band On Channel (IBOC) terrestrial Digital Audio Broadcasting (DAB) is ill-conceived.
    [Show full text]
  • Radio Broadcasting Equipment Catalog
    Radio Broadcasting Equipment Catalog Digital and Analog equipment Best Audio Quality with maximum AC Efficiency “Tailor-made” customized Turnkey Solutions One size doesn’t fit all 4 Radio Broadcasting Equipment Radio Broadcasting Equipment 5 Radio & TV Broadcasting Equipment 40 years of experience Our difference +160 Countries The unique way we mix together our ingredients in order to offer you the best specific solution for + 50,000 Radio & TV Projects your unique and specific project. + 20,000 Transmitters Installed Millions of People Connected dbbroadcast.com 6 Radio Broadcasting Equipment Radio Broadcasting Equipment 7 Main Benefits The highest AC efficiency Radio products and solutions The outstanding AC efficiency is made possible thanks to the optimized RF design –Green RF™ - combined with the last generation LDMOS active components, that allows the highest DC to RF efficiency and very low lossesmatching circuits and combining systems. DB is leader in FM digital and analog broadcasting products. In more than 40 years we design The new switch-mode power supplies, with over 94% efficiency, contribute reaching top our products to offer to broadcasting operators the best quality of audio signal while providing efficiency performance. the maximum AC efficiency, dramatically reducing energy costs. Moreover, the top-level AC efficiency is reached over a very wide range of power, thanks to the The GREEN RF™ technology, combined with the new 65:1 devices, is the latest evolution of the smart Automatic Level Control system that acts on internal parameters of the amplifier. world-famous DB patented COLD-FET™ technology, already present in DB’s FM transmitters. Rugged and Long lasting Reliability PFG and Mozart Series, the new line of FM transmitters and exciters, have been awarded some of the industry’s most prestigious technology honors, the Best of Show Award at both NAB Show Each product has been designed to give broadcasters a very reliable, long-lasting equipment.
    [Show full text]
  • Recommendations on Issues Related to Digital Radio Broadcasting in India 1St February, 2018 Mahanagar Doorsanchar Bhawan Jawahar
    Recommendations on Issues related to Digital Radio Broadcasting in India 1st February, 2018 Mahanagar Doorsanchar Bhawan Jawahar Lal Nehru Marg New Delhi-110002 Website: www.trai.gov.in i Contents INTRODUCTION ................................................................................................... 1 CHAPTER 2: Digital Radio Broadcasting Technologies and International Scenario .............................................................................................................. 5 CHAPTER 3: Issues Related to Digitization of FM Radio Broadcasting .............. 15 CHAPTER 4: Summary of Recommendations .................................................... 40 ii CHAPTER 1 INTRODUCTION 1.1 Radio remains an integral part of India‟s rich culture, social and economic landscape. Radio broadcasting1 is one of the most popular and affordable means for mass communication, largely owing to its wide coverage, low set up costs, terminal portability and affordability. 1.2 At present, analog terrestrial radio broadcast in India is carried out in Medium Wave (MW) (526–1606 KHz), Short Wave (SW) (6–22 MHz), and VHF-II (88–108 MHz) spectrum bands. VHF-II band is popularly known as FM band due to deployment of Frequency Modulation (FM) technology in this band. AIR - the public service broadcaster - has established 467 radio stations encompassing 662 radio transmitters, which include 140 MW, 48 SW, and 474 FM transmitters for providing radio broadcasting services2. It also provides overseas broadcasts services for its listeners across the world. 1.3 Until 2000, AIR was the sole radio broadcaster in the country. In the year 2000, looking at the changing market dynamics, the government took an initiative to open the FM radio broadcast for private sector participation. In Phase-I of FM Radio, the government auctioned 108 FM radio channels in 40 cities. Out of these, only 21 FM radio channels became operational and subsequently migrated to Phase-II in 2005.
    [Show full text]
  • A 300 W Power Amplifier for the 88 to 108 Mhz FM Broadcast Band
    High Frequency Design From April 2008 High Frequency Electronics Copyright © 2008 Summit Technical Media LLC LDMOS FM AMPLIFIER A 300 W Power Amplifier for the 88 to 108 MHz FM Broadcast Band By Antonio Eguizabal Freescale Semiconductor he intention of this This article describes an FM article is to present band power amplifier, Ta 300 watt single- including circuit design, ended RF power amplifi- thermal considerations, er for the FM broadcast construction notes and per- band, used in small to formance measurements medium radio stations in which economy and flexi- bility are important to the user. With the recent availability of low cost overmolded plastic LDMOS RF power amplifi- er transistors, such as the Freescale family of MRF6VXXXXN devices, it is possible to design Figure 1 · Assembled test fixture (top view). and build a low cost, compact, broadband power amplifier offering simplicity and relia- bility. area and ERP has a minimum field strength In this article, an RF power amplifier using of 70 dBµV or 3.16 mV/m [2]. the low cost OMP Freescale MRF6V2300N LDMOS transistor is presented (photo in Introduction Figure 1). It operates at Vdd = 50 VDC with an The Freescale MRF6V2300N is a 10 to 450 average drain efficiency in excess of 60% and MHz 300 W LDMOS RF transistor in a TO- a gain of 24 dB with a 1 dB gain flatness over 272 WB plastic package featuring 25.5 dB the 88 MHz to 108 MHz band. No tuning is gain and 68% efficiency at 220 MHz, operating required as the amplifier is broadband.
    [Show full text]