Amplifiers

A Method of Measuring Large-signal S-parameters of High Power Transistors

Determination of large-signal scattering parameters of high power transistors from measured data during normal operation
TECHNICAL FEATURE A Method of Measuring Large-signal S-parameters of High Power Transistors A measurement method for scattering parameters (S-parameters) of high power transistors is presented. The proposed method directly determines the S-parameters of high power transistors by measuring overall gain, phase and S-parameters of input and output matching network...
Read More

Improved Gain for a Dynamic Envelope Tracking Amplifier in Cellular Radio Handsets

Use of varactor diode to improve gain in an envelope tracking amplifier in third generation cellular phones
TECHNICAL FEATURE Improved Gain for a Dynamic Envelope Tracking Amplifier in Cellular Radio Handsets An envelope tracking (ET) amplifier with variable bias voltage is a potentially more efficient power amplifier technique for third generation cellular phones. However, the input and output impedances of the transistors vary with the bias...
Read More

Wireless Telecommunications Testing with S-series Microwave Power Amplifiers

Introduction to a line of amplifiers optimized for wireless telecommunication test use
PRODUCT FEATURE Wireless Telecommunications Testing with S-series Microwave Power Amplifiers Amplifier Research Souderton, PA Amplifier Research offers a broad range of power amplifiers covering DC to 40 GHz with output power ranging from 1 to 10,000 W. While applications include electromagnetic compatibility (EMC) testing, RF component testing, physics (plasma...
Read More

Adaptive Feedforward Amplifier Linearizer Using Analog Circuitry

Description of a typical feedforward architecture along with the simulation results of a compensation technique using the least mean square algorithm
TECHNICAL FEATURE Adaptive Feedforward Amplifier Linearizer Using Analog Circuitry Alfonso J. Zozaya, Eduard Bertran Albertí and Jordi Berenguer-Sau Dept. of Signal Theory and Communications Polytechnic University of Catalonia Barcelona, Spain Nowadays, feedforward is the most effective and broadly used linearization technique employed in modern multi-carrier communications systems. Different versions,...
Read More

Power Efficient MMIC Frequency Triplers

Presentation of an approach to optimize the power efficiency of an MMIC frequency tripler
TECHNICAL FEATURE Power Efficient MMIC Frequency Triplers The design of an efficient frequency tripler for an S-/X-band communications receiver is described. An approach for optimizing the tripler for best power efficiency is presented. The tripler topology consists of the harmonic generator circuit, a bandpass filter and an amplifier. A...
Read More

SiGe Power Amplifier ICs with SWR Protection for Handset Applications

Detailed description of how SiGe technology is used to develop power amplifier ICs for wireless handset applications
TECHNICAL FEATURE SiGe Power Amplifier ICs with SWR Protection for Handset Applications Joe Pusl and Srikanth Sridharan IBM San Diego RFIC Design Center Encinitas, CA Philip Antognetti, David Helms, Anurag Nigam, James Griffiths, Kenneth Louie and Mark Doherty IBM Boston RFIC Design Center Lowell, MA In recent years there...
Read More