Monday January 30, 2017 at 2:10 p.m. Professor Carlos Saavedra, Queen’s University and Associate Editor of the IEEE Transactions on Microwave Theory and Techniques, will be presenting “Intermodulation Distortion Mitigation in Microwave Amplifiers and Frequency Converters”.
Speaker: Professor Carlos Saavedra
Queen’s University, Kingston
Associate Editor of the IEEE Transactions on Microwave Theory and Techniques
Day & Time: Monday, January 30th, 2017
2:10 pm – 3:00 pm
Location: Room WB116, Wallberg Building
184 College St, Toronto, ON M5S 3E4
Contact: Dustin Dunwell
Organizer: Solid State Circuit Society
Cost: Free for everyone. Complimentary refreshments will be provided.
Abstract: Intermodulation distortion (IMD) refers to the phenomenon where the spectral lines of an information‐bearing signal interact with themselves to yield new, undesired, spectral lines as they pass through a circuit. While some of the spurious tones are easily eliminated through filtering, others are more difficult to deal with because they appear within the band of the information signal and interfere with it. The study of IMD has a rich history and multiple techniques have been developed over time to mitigate it. One such method is known as derivative superposition (DS), which reduces IMD distortion by using an auxiliary circuit to generate an out‐of‐phase replica of the IMD tones produced by the main circuit. First introduced in the late 1990s, DS has attracted much attention due to its small footprint and low power consumption. This talk will discuss work we have carried out at Queen’s that uses DS and digital assist to improve the output third‐order intercept point (OIP3) of gallium‐nitride (GaN) power amplifiers from by +40 dBm to +50 dBm over a 5 GHz span. A stand‐alone distortion cancelling cell will also be presented which can improve the OIP3 of a generic off‐the‐shelf microwave amplifier by 7.5 dB. The talk will conclude with a discussion of mixer linearization using DS and digital assist techniques.
Biography: Carlos Saavedra obtained the Ph.D. degree from Cornell University, Ithaca, New York, in 1998. From 1998 to 2000 he was a Senior Engineer at Millitech Corporation (North Hampton, Massachusetts) and in 2000 he joined Queen’s University at Kingston where he currently holds the rank of Professor. He is an Associate Editor of the IEEE Transactions on Microwave Theory and Techniques, is a member of the Technical Program Review Committee of the IEEE International Microwave Symposium (IMS) and of the Steering Committee of the IEEE NEWCAS conference. He is Past Chair of the IEEE MTT‐S Technical Coordinating Committee (TCC‐22) on Signal Generation and Frequency Conversion and was Guest Editor of the September 2013 IEEE Microwave Magazine Focus Issue titled “100 Years of Mixer Technology”. He served on the Steering and Technical Program Committees of the 2012 IEEE IMS and was a member of the IEEE RFIC Symposium TPC from 2008 to 2011. Prof. Saavedra is a three‐time recipient of the third‐year ECE undergraduate teaching award at Queen’s University.