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We also offer the following speakers for local MTT chapters through the MTT Speakers Bureau

(www.mtt.org/speakers-bureau.html):

Mr. Timothy Boles, M/A-COM

"A Fully Monolithic HMIC Low Noise Amplifier"

Abstract: A two/three stage monolithic silicon low noise amplifier has been designed utilizing SPICE modeling techniques.

The circuit design architecture is based on high frequency, small signal BJT's, consisting of a common emitter stage at the

input and a Darlington configured pair at the device output. This paper will also cover the techniques and technology

required to fabricate these monolithic high frequency circuits.

"Design of Darlington Based Silicon MMIC Gain Blocks"

Abstract: In many wireless and CATV applications, the use of silicon MMIC gain blocks have replaced discrete devices for

low level gain stages and medium power amplification. The gain blocks have become quite cost competitive in volume

when compared with the discrete transistors and have the advantage of providing flat power gain while being matched

to the required circuit impedances. Design concepts are presented.

Contact address: Tel: 781-564-3386 · Fax: 781-564-3141 · e-mail: HYPERLINK "mailto:bolest@amp.com"bolest@amp.com

Dr. Robert Caverly, Villanova University

"RF and Microwave Solid-State Control"

Abstract: A variety of semiconductor technologies is now available for RF and microwave control. This talk will address

such control technologies as PIN diodes and FET-based elements and issues related to the choice of control technology

for particular applications. Control design considerations will also be discussed.

"RF Aspects of Magnetic Resonance Imaging”

Abstract: Magnetic Resonance Imaging (MRI) scanners are an important diagnostic tool for the medical

practitioner. MRI provides a non-invasive means of imaging soft tissues and to obtain real-time images of blood

flow through the body. MRI scanners rely heavily on several topical areas of interest to Electrical Engineers:

image processing, high speed computing and RF systems and components. This presentation will focus on the RF

aspects of Magnetic Resonance Scanners. A primer on the physical phenomenon behind magnetic resonance will

be covered along with a high level overview of the various components making up conventional MRI systems.

Included in this high level overview will be an introduction to the various coils that make up MR scanners and

system diagrams for both the transmit and receive paths. The talk with then narrow in scope to look at how RF

signals are controlled in both transmit and receive coils with PIN diodes, an area of research currently underway at

Villanova University.

Contact address: Tel: 610-519-5660 · Fax: 610-519-4436 · e-mail: HYPERLINK "mailto:r.caverly@ieee.org"r.caverly@ieee.org

Dr. Steve C Cripps

"High Efficiency Amplification of Variable Envelope Signals for Modern Wireless

Communications Systems: Doherty and Chireix Re-visited"

Abstract: Modern wireless systems pose severe challenges for the RF PA designer, both at the mobile end, where

efficiency is paramount, and at basestation, which may require multi-channel operation. Most systems use phase-shift

modulation but usually have accompanying envelope variations in order to limit channel bandwidth. This talk will review

the basic theory of the Doherty technique and the Chireix outphasing method for designing such future systems.

Contact address: Tel: 44-0-1460-234296 · Fax: 44-0-1460-234296 · e-mail: HYPERLINK "mailto:Steve.Cripps@BTInternet.com"Steve.Cripps@BTInternet.com

Prof. Jozef W. Modelski

"Microwave Phase Modulators and Shifters"

Abstract: This lecture presents an overview of digital and continuous phase modulators and shifters with semiconductor

(varactor diodes, pin diodes, FETs) and ferrite elements. Design methods and optimization procedures of different shifter

structures for receiving: maximum shifter bandwidth, minimum parasitic amplitude modulation, high efficiency, maximum

linearity of phase characteristics (for analog phase shifters) are given, particularly, for varactor diode analog and pin

diode digital modulators. Practical realizations in different technologies and in different frequency bands are also

presented.

Contact address: Warsaw University of Technology, Institute of Radioelectronics · Nowowiejska str., 15/19,00-665

Warsaw, Poland · Tel: 48-22-8253929 or 48-22-8256555 · Fax: 48-22-8255248 or 48-22-8256555 · e-mail:

HYPERLINK "mailto:j.modelski@ire.pw.edu.pl"j.modelski@ire.pw.edu.pl

Frederick H. Raab, Green Mountain Radio Research

"High-efficiency RF-power amplifiers and Transmitters"

Abstract: This talk is an overview of techniques for high-efficiency RF power amplification. First, some basic concepts about

transistors and the concept of average efficiency are introduced. The characteristics of conventional amplifiers (classes A,

B, and C) are then reviewed. The principles, demonstrated achievements, and practical limitations of RF-power amplifiers

operating in class D, class E, and class F are then discussed. The talk concludes with a discussion of techniques for linear

amplification using high-level amplitude modulation via a class-S modulator and the Kahn envelope-elimination and

restoration technique.

"Kahn-Technique Transmitters"

Abstract: The Kahn envelope-elimination and restoration (EER) technique allows efficient but nonlinear RF amplifiers to be

used to implement a high-efficiency linear transmitter. Fundamentally, a narrowband RF signal is regarded as

simultaneous amplitude and phase modulation. The phase-modulated carrier is amplified efficiently by a chain of nonlinear

RF amplifiers and the envelope is restored by high-level amplitude modulation of the final amplifier. This talk reviews the

concept of average efficiency and then reviews the principles and requirements for the EER technique.

"Low-Cost High-Efficiency HF Power Amplifiers"

Abstract: Recently marketed "low-cost" RF-power MOSFETs in plastic TO-247 packages are capable of generating

significant RF power at high efficiency in single-frequency RF applications. This paper explores the use of these MOSFETs

in broadband power amplifiers. PAs operating in classes D, DE, and E are compared.

Contact address: Tel: 802-655-9670 · Fax: 802-655-9760 · e-mail: HYPERLINK "mailto:f.raab@ieee.org"f.raab@ieee.org

Nathan O. Sokal, Design Automation, Inc.

"Class E Switching-Mode High-Efficiency Power Amplifiers - from HF to Microwave"

Abstract: Class E power amplifiers achieve significantly higher efficiency than for conventional Class B or C. Class E

operates the transistor as an on/off switch and "shapes the voltage and current waveforms" to prevent simultaneous

high voltage and high current in the transistor; that minimizes the power dissipation, especially during the switching

transitions. In the published low-order class-E circuit, a transistor performs well at frequencies up to about 70% of its

frequency of good class-B operation.

- Four (4) hour Tutorial Lecture "RF Power Amplifiers, Classes A through S - How They

Operate, and When to Use Each"

Abstract: With at least ten lettered classes of RF power amplifiers, and several combinations of these classes, many

engineers are confused about RF power amplifiers. The complexity of the subject is compounded by the fact that RF

power transistor acts either as a high-resistance current source or as a low-resistance switch, or - in some amplifiers - as

a high-resistance current source during part of the "on" interval and as a low-resistance switch during another part of the

"on" interval (mixed-mode operation). The circuit topology does not define unambiguously the transistor operating mode

or the amplifier class of operation.

Contact address: Nathan O. Sokal, President · Design Automation, Inc. · 4 Tyler Road, Lexington, MA 02420-2404, U.S.A.

Tel. +1 (781) 862-8998 · Email: nathansokal@gmail.com · Skype: nathansokal

Dr. Allen Katz, Prof. E/CE TCNJ, Linearizer Technology, Inc.

"Minimizing Power Amplifier Memory Effects"

Abstract: Memory effects are changes in an amplifiers non-linear characteristics resulting from the past history of the

input signal. Predistortion linearization depends on a stable non-linear response, and can be significantly degraded by

memory effects. This presentation will begin with an overview of linearization techniques and the application of digital

signal processing (DSP) to the correction of distortion in power amplifiers. The problems caused by memory effects will be

introduced, Different sources of memory effects will be discussed and techniques for their suppression presented.

"Linearization: Reducing Distortion in Power Amplifiers"

Abstract: Our Society?s need to exchange greater and greater amounts of information has created an unprecedented

demand for highly linear power amplifiers. High linearity is required for the spectrally efficient transmission of information.

This presentation will discuss techniques for the cancellation of distortion that are also known as linearization.

Different methods of linearization including digital approaches will be introduced and compared. The linearization of solid-

state power amplifiers, traveling wave tubes amplifiers and klystron power amplifiers will be considered. Criteria for the

evaluation of linearity will be reviewed and special attention given to problems unique to SSPAs.

Contact address: Dr. Allen Katz, Prof. E/CE TCNJ, President · Linearizer Technology, Inc. · Tel 609-584-8424 · Cel 609-947-

3889 · Email: a.katz@ieee.org