Power Amplifier Principles and Modern Design Techniques
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RF CMOS Power Amplifiers: Theory, Design and Implementation the KLUWER INTERNATIONAL SERIES in ENGINEERING and COMPUTER SCIENCE
RF CMOS Power Amplifiers: Theory, Design and Implementation THE KLUWER INTERNATIONAL SERIES IN ENGINEERING AND COMPUTER SCIENCE ANALOG CIRCUITS AND SIGNAL PROCESSING Consulting Editor: Mohammed Ismail. Ohio State University Related Titles: POWER TRADE-OFFS AND LOW POWER IN ANALOG CMOS ICS M. Sanduleanu, van Tuijl ISBN: 0-7923-7643-9 RF CMOS POWER AMPLIFIERS: THEORY, DESIGN AND IMPLEMENTATION M.Hella, M.Ismail ISBN: 0-7923-7628-5 WIRELESS BUILDING BLOCKS J.Janssens, M. Steyaert ISBN: 0-7923-7637-4 CODING APPROACHES TO FAULT TOLERANCE IN COMBINATION AND DYNAMIC SYSTEMS C. Hadjicostis ISBN: 0-7923-7624-2 DATA CONVERTERS FOR WIRELESS STANDARDS C. Shi, M. Ismail ISBN: 0-7923-7623-4 STREAM PROCESSOR ARCHITECTURE S. Rixner ISBN: 0-7923-7545-9 LOGIC SYNTHESIS AND VERIFICATION S. Hassoun, T. Sasao ISBN: 0-7923-7606-4 VERILOG-2001-A GUIDE TO THE NEW FEATURES OF THE VERILOG HARDWARE DESCRIPTION LANGUAGE S. Sutherland ISBN: 0-7923-7568-8 IMAGE COMPRESSION FUNDAMENTALS, STANDARDS AND PRACTICE D. Taubman, M. Marcellin ISBN: 0-7923-7519-X ERROR CODING FOR ENGINEERS A.Houghton ISBN: 0-7923-7522-X MODELING AND SIMULATION ENVIRONMENT FOR SATELLITE AND TERRESTRIAL COMMUNICATION NETWORKS A.Ince ISBN: 0-7923-7547-5 MULT-FRAME MOTION-COMPENSATED PREDICTION FOR VIDEO TRANSMISSION T. Wiegand, B. Girod ISBN: 0-7923-7497- 5 SUPER - RESOLUTION IMAGING S. Chaudhuri ISBN: 0-7923-7471-1 AUTOMATIC CALIBRATION OF MODULATED FREQUENCY SYNTHESIZERS D. McMahill ISBN: 0-7923-7589-0 MODEL ENGINEERING IN MIXED-SIGNAL CIRCUIT DESIGN S. Huss ISBN: 0-7923-7598-X CONTINUOUS-TIME SIGMA-DELTA MODULATION FOR A/D CONVERSION IN RADIO RECEIVERS L. -
BETS-5 Issue 1 November 1, 1996
BETS-5 Issue 1 November 1, 1996 Spectrum Management Broadcasting Equipment Technical Standard Technical Standards and Requirements for AM Broadcasting Transmitters Aussi disponible en français - NTMR-5 Purpose This document contains the technical standards and requirements for the issuance of a Technical Acceptance Certificate (TAC) for AM broadcasting transmitters. A certificate issued for equipment classified as type approved or as technically acceptable before the coming into force of these technical standards and requirements is considered to be a valid and subsisting TAC. A Technical Acceptance Certificate is not required for equipment manufactured or imported solely for re-export, prototyping, demonstration, exhibition or testing purposes. i Table of Contents Page 1. General ...............................................................1 2. Testing and Labelling ..................................................1 3. Standard Test Conditions ..............................................2 4. Transmitting Equipment Standards .....................................3 5. Equipment Requirements ..............................................4 6. RF Carrier Performance Standards .................................... 5 6.1 Power Output Rating .................................................5 6.2 Modulation Capability ................................................5 6.3 Carrier Frequency Stability ............................................6 6.4 Carrier Level Shift ...................................................7 6.5 Spurious Emissions -
Signal Issue 35
Signal Issue 35 Tricks of the Trade Dave Porter G4OYX and Alan Beech G1BXG We continue to celebrate the 50th anniversary of the start of offshore commercial radio in the UK and are now in June 1965. By this time, the number of stations on the air was increasing steadily, taking advantage of the (lack of) laws at the time with regard to operations in International Waters. The first two stations, Caroline and Atlanta, had used 10 kW AM transmitters by Continental Electronics employing their patented version of screen grid modulation but, just prior to Christmas 1964, the US-inspired and -built station of Radio London on the former US minesweeper USS Density renamed M/V Galaxy was on the air with test transmissions on 266 m, 1124 kHz, running, at first, 17 kW. This 50 kW transmitter was an RCA BTA-50H and was the first of many in the offshore fleet to employ the ‘Ampliphase’ approach. From ‘outphasing’ to ‘Ampliphase’ Amplitude from phase The theory of what became known as ‘Ampliphase’ was The principle of ‘Ampliphase’ is to take a single frequency proposed and developed in France by Henry Chireix in drive source, split it into two feeds, phase modulate each 1935 who called the technique ‘outphasing’. feed, amplify as required and add the two signals in a combining network. Amplitude modulation is achieved by ‘Outphasing’ was not taken up initially by RCA but by the degree of addition or subtraction due to the phase McClatchy Broadcasting in the late 1940s, first at KFBK, difference between the two signals. -
Valve Biasing
VALVE AMP BIASING Biased information How have valve amps survived over 30 years of change? Derek Rocco explains why they are still a vital ingredient in music making, and talks you through the mysteries of biasing N THE LAST DECADE WE HAVE a signal to the grid it causes a water as an electrical current, you alter the negative grid voltage by seen huge advances in current to flow from the cathode to will never be confused again. When replacing the resistor I technology which have the plate. The grid is also known as your tap is turned off you get no to gain the current draw required. profoundly changed the way we the control grid, as by varying the water flowing through. With your Cathode bias amplifiers have work. Despite the rise in voltage on the grid you can control amp if you have too much negative become very sought after. They solid-state and digital modelling how much current is passed from voltage on the grid you will stop have a sweet organic sound that technology, virtually every high- the cathode to the plate. This is the electrical current from flowing. has a rich harmonic sustain and profile guitarist and even recording known as the grid bias of your amp This is known as they produce a powerful studios still rely on good ol’ – the correct bias level is vital to the ’over-biased’ soundstage. Examples of these fashioned valves. operation and tone of the amplifier. and the amp are most of the original 1950’s By varying the negative grid will produce Fender tweed amps such as the What is a valve? bias the technician can correctly an unbearable Deluxe and, of course, the Hopefully, a brief explanation will set up your amp for maximum distortion at all legendary Vox AC30. -
Chapter 4, Current Status, Knowledge Gaps, and Research Needs Pertaining to Firefighter Radio Communication Systems
NIOSH Firefighter Radio Communications CHAPTER IV: STRUCTURE COMMUNICATIONS ISSUES Buildings and other structures pose difficult problems for wireless (radio) communications. Whether communication is via hand-held radio or personal cellular phone, communications to, from, and within structures can degrade depending on a variety of factors. These factors include multipath effects, reflection from coated exterior glass, non-line-of-sight path loss, and signal absorption in the building construction materials, among others. The communications problems may be compounded by lack of a repeater to amplify and retransmit the signal or by poor placement of the repeater. RF propagation in structures can be so poor that there may be areas where the signal is virtually nonexistent, rendering radio communication impossible. Those who design and select firefighter communications systems cannot dictate what building materials or methods are used in structures, but they can conduct research and select the radio system designs and deployments that provide significantly improved radio communications in this extremely difficult environment.4 Communication Problems Inherent in Structures MULTIPATH Multipath fading and noise is a major cause of poor radio performance. Multipath is a phenomenon that results from the fact that a transmitted signal does not arrive at the receiver solely from a single straight line-of-sight path. Because there are obstacles in the path of a transmitted radio signal, the signal may be reflected multiple times and in multiple paths, and arrive at the receiver from various directions along various paths, with various signal strengths per path. In fact, a radio signal received by a firefighter within a building is rarely a signal that traveled directly by line of sight from the transmitter. -
Bias Circuits for RF Devices
Bias Circuits for RF Devices Iulian Rosu, YO3DAC / VA3IUL, http://www.qsl.net/va3iul A lot of RF schematics mention: “bias circuit not shown”; when actually one of the most critical yet often overlooked aspects in any RF circuit design is the bias network. The bias network determines the amplifier performance over temperature as well as RF drive. The DC bias condition of the RF transistors is usually established independently of the RF design. Power efficiency, stability, noise, thermal runway, and ease to use are the main concerns when selecting a bias configuration. A transistor amplifier must possess a DC biasing circuit for a couple of reasons. • We would require two separate voltage supplies to furnish the desired class of bias for both the emitter-collector and the emitter-base voltages. • This is in fact still done in certain applications, but biasing was invented so that these separate voltages could be obtained from but a single supply. • Transistors are remarkably temperature sensitive, inviting a condition called thermal runaway. Thermal runaway will rapidly destroy a bipolar transistor, as collector current quickly and uncontrollably increases to damaging levels as the temperature rises, unless the amplifier is temperature stabilized to nullify this effect. Amplifier Bias Classes of Operation Special classes of amplifier bias levels are utilized to achieve different objectives, each with its own distinct advantages and disadvantages. The most prevalent classes of bias operation are Class A, AB, B, and C. All of these classes use circuit components to bias the transistor at a different DC operating current, or “ICQ”. When a BJT does not have an A.C. -
UNIVERSITY of CALIFORNIA, SAN DIEGO CMOS RF Power Amplifier Design Approaches for Wireless Communications a Dissertation Submitt
UNIVERSITY OF CALIFORNIA, SAN DIEGO CMOS RF Power Amplifier Design Approaches for Wireless Communications A dissertation submitted in partial satisfaction of the requirements for the degree Doctor of Philosophy in Electrical Engineering (Electronic Circuits and Systems) by Sataporn Pornpromlikit Committee in charge: Professor Peter M. Asbeck, Chair Professor Prabhakar R. Bandaru Professor Andrew C. Kummel Professor Lawrence E. Larson Professor Paul K.L. Yu 2010 Copyright Sataporn Pornpromlikit, 2010 All rights reserved. The dissertation of Sataporn Pornpromlikit is approved, and it is acceptable in quality and form for publication on micro- film and electronically: Chair University of California, San Diego 2010 iii DEDICATION To my family. iv EPIGRAPH ”Education is what remains after one has forgotten what one has learned in school.” — Albert Einstein v TABLE OF CONTENTS Signature Page................................... iii Dedication...................................... iv Epigraph.......................................v Table of Contents.................................. vi List of Figures.................................... viii List of Tables.................................... xi Acknowledgements................................. xii Vita......................................... xiv Abstract of the Dissertation............................. xv Chapter 1 Introduction.............................1 1.1 CMOS Technology and Scaling...............2 1.2 Toward Fully-Integrated CMOS Transceivers........4 1.3 Power Amplifier Design...................5 -
5 Steps to Selecting the Right RF Power Amplifier
modular rf 5 Steps to Selecting the Right RF Power Amplifier Jason Kovatch Sr. Development Engineer AR Modular RF, Bothell WA You need an RF power amplifier. You have measured the power of your signal and it is not enough. You may even have decided on a power level in Watts that you think will meet your needs. Are you ready to shop for an amplifier of that wattage? With so many variations in price, size, and efficiency for amplifiers that are all rated at the same number of Watts many RF amplifier purchasers are unhappy with their selection. Some of the unfortunate results of amplifier selection by Watts include: unacceptable distortion or interference, insufficient gain, premature amplifier failure, and wasted money. Following these 5 steps will help you avoid these mistakes. Step 1 - Know Your Signal Step 2 – Do the Math Step 3 - Window Shopping Step 4 - Compare Apples to Apples Step 5 – Shopping for Bells and Whistles Step 1 – Know Your Signal You need to know 2 things about your signal: what type of modulation is on the signal and the actual Peak power of your signal to be amplified. Knowing the modulation is the most important as it defines broad variations in amplifiers that will provide acceptable performance. Knowing the Peak power of your signal will allow you calculate your gain and/or power requirements, as shown in later steps. Signal Modulation and Power- CW, SSB, FM, and PM are Easy To avoid distortion, amplifiers need to be able to faithfully process your signal’s peak power. -
Chapter 4 BJT BIASING CIRCUIT Introduction – Biasing the Analysis Or Design of a Transistor Amplifier Requires Knowledge of Both the Dc and Ac Response of the System
Chapter 4 BJT BIASING CIRCUIT Introduction – Biasing The analysis or design of a transistor amplifier requires knowledge of both the dc and ac response of the system. In fact, the amplifier increases the strength of a weak signal by transferring the energy from the applied DC source to the weak input ac signal The analysis or design of any electronic amplifier therefore has two components: •The dc portion and •The ac portion During the design stage, the choice of parameters for the required dc levels will affect the ac response. What is biasing circuit? Biasing: Application of dc voltages to establish a fixed level of current and voltage. Purpose of the DC biasing circuit • To turn the device “ON” • To place it in operation in the region of its characteristic where the device operates most linearly . •Proper biasing circuit which it operate in linear region and circuit have centered Q-point or midpoint biased •Improper biasing cause Improper biasing cause •Distortion in the output signal •Produce limited or clipped at output signal Important basic relationship IECB= II + I β = C I B IE =+≅ (β 1) IIBC VVVCB= CE − BE Operating Point •Active or Linear Region Operation Base – Emitter junction is forward biased Base – Collector junction is reverse biased Good operating point •Saturation Region Operation Base – Emitter junction is forward biased Base – Collector junction is forward biased •Cutoff Region Operation Base – Emitter junction is reverse biased BJT Analysis DC AC analysis analysis Calculate gains of the Calculate the DC Q-point amplifier -
Hans Knot International Radio Report April 2016 Welcome to Another
Hans Knot International Radio Report April 2016 Welcome to another edition of the International Radio Report. Thanks all for your e mails, memories, photos, questions and more. Part of the report is what was left after the March edition was totally filled and so let’s go with this edition in which first there’s space for a story I wrote last months after again doing some research: ‘Ronan O’Rahilly, Georgie Fame and the Blue Fames. Where it really went wrong!’ On this subject I’ve written before but let’s go back in time and also add some new facts to it: ‘Was Ronan O’Rahilly the manager of Georgie Fame?’ I can tell you there was a problem with an important instrument. When in April 1964 Granada Television came with an edition of the ‘World in action’ series, which was a production from Michael Hodges, they informed the television public about a new form of Piracy, the watery pirates. Two radio ships bringing music and entertainment under the names of Radio Caroline and Radio Atlanta. Radio Caroline was the first 20th century Pirate off the British coast with programs, at that stage, for 12 hours a day. Interviews with the Caroline people were made in the offices of Queen Magazine in the city of London and included – among others – Jocelyn Stevens and the then 23-year old Irish Ronan O’Rahilly. During this documentary it became known, which we would also read in several newspapers in the then following weeks, that Ronan O’Rahilly had started his radiostation Caroline as he couldn’t get his artists played on stations like Radio Luxembourg. -
Fcc and Am Stereo: a Deregulatory Breach of Duty
THE FCC AND AM STEREO: A DEREGULATORY BREACH OF DUTY JASON B. MEYERt The trend toward governmental deregulation of private enterprise, which began in earnest in the 1970's1 and has gathered momentum under the Reagan administration, has had a significant effect on the telecommunications industry. The Federal Communications Commis- sion (FCC) has reduced regulation of operation and maintenance log- ging2 and eliminated minimum aural transmission power require- ments.' Similarly, a major effort has been made in Congress to enact a bill deregulating broadcast programming.4 In 1984 the FCC justified eliminating or relaxing many licensing requirements on the grounds that such "actions further the Commission's goals of creating, to the maximum extent possible, an unregulated, competitive environment for t A.B. 1980, Princeton University; J.D. Candidate, 1985, University of Pennsylva- nia. The author wrote this Comment while a student at the University of Pennsylvania Law School. I See, e.g., Depository Institutions Deregulation and Monetary Control Act of 1980, Pub. L. No. 96-221, 94 Stat. 132 (codified at scattered sections of Titles 12, 15, 22 & 42 of the U.S.C.) (reducing regulatory control of banks); Airline Deregulation Act of 1978, Pub. L. No. 95-504, 92 Stat. 1705 (codified at 49 U.S.C. §§ 1300-02, 1305-08, 1324, 1341, 1371-79, 1382, 1384, 1386, 1389, 1461, 1482, 1486, 1490, 1504, 1551-52) (reducing regulatory control of airlines). I See Operating and Maintenance Logs for Broadcast and Broadcast Auxiliary Stations, 48 Fed. Reg. 38,473 (1983). ' The Commission abolished minimum aural power requirements that had previ- ously created a situation in which a station's aural range well exceeded its visual range. -
Prof. K Radhakrishna Rao Lecture 2 Role of Analog Signal Processing
Analog Circuits and Systems Prof. K Radhakrishna Rao Lecture 2 Role of Analog Signal Processing in Electronic Products – Part 1 1 Structure of an electronic product 2 Electronic Products o Process analog signals and digital data o This involve transmission and reception of signals and data o It is generally necessary to code signal and data to transmit over channels o Transmission can be over wires or wireless o Processing and storage are efficient in digital form o Several human interface technologies are available 3 Products considered o Radio Receiver o Modem o Cell Phone o ECG 4 Radio Receiver o AM Receiver o FM Receiver 5 Radio waves are classified as o Low frequency (LF): 30 kHz – 300 kHz, o Medium frequency (MF): 300 kHz – 3 MHz, o High frequency (HF): 3 MHz – 30 MHz, o Very high frequency (VHF): 30 MHz – 300 MHz, o Ultra high frequency (UHF): 300 MHz – 3 GHz, o Super high frequency (SHF): 3 GHz – 30 GHz, o Extremely high frequency (EHF): 30 GHz to 300 GHz. 6 Radio broadcasting o one-way wireless transmission over radio waves to reach a wide audience o takes place in MF (300 kHz – 3 MHz), HF (3 MHz – 30 MHz) and VHF (30 MHz – 300 MHz) regions 7 Major modes of radio broadcasting o Sine wave (single tone) represented by Vtp sin(ωφ+ ) PM (Analog) where φ = phase in radians PSK (Digital) QPSK( Digital) FM (Analog) ω = frequency in rad/sec FSK (Digital) AM, DSB (Analog) V = peak magnitude in volts p ASK (Digital) 8 AM broadcasting o Amplitude of the carrier signal is varied in response to the amplitude of the signal to be transmitted o Amplitude modulation is done by a unit called mixer (nothing but a multiplier) which produces an output output=+( Vpc V pm sinωω m t )sin c t Vpm where ωm is the modulating frequency = m is known as the Vpc ω is the carrier frequency c modulation index.