Penina Axelrad has built her career pushing the boundaries of GPS technology.
As a faculty member in the Ann and H.J. Smead Department of Aerospace Engineering Sciences, she has earned accolades from her peers, served in leadership positions, taught hundreds and hundreds of students, been inducted into the National Academy of Engineering, and now has been named a Distinguished Professor by the University of Colorado Board of Regents, the highest honor bestowed on faculty.
“Penny sees things differently than most people, particularly most professors that I know. She can assess a situation and see things that were invisible to most others, and if we compare notes, there is always something for me to learn,” said Brian Argrow, chair of Smead Aerospace. “It is the ability to synthesize facts and ideas into a coherent picture with insights that distinguishes great engineers from good engineers. Penny has honed this ability in teaching and research.”
Growing up, Axelrad excelled in math and science and was accepted to the Massachusetts Institute of Technology.
She was planning to major in electrical engineering, but struck out when trying to get experience working in one of the EE labs as a freshman.
“The professors basically told me to come back after I’d taken more classes and preferably gotten A’s. A friend in Aero/Astro recommended trying the Space Systems Lab instead, where I totally lucked out and got the chance to learn to build and test circuit boards,” Axelrad said.
She quickly found her place.
As a child, Axelrad had been fascinated by the Apollo program; she completed her bachelor’s and master’s degrees in aeronautical and astronautical engineering at MIT. She then went on to Stanford for a PhD, which she earned in 1991.
Axelrad worked for about two years in industry in the Bay Area, also teaching a class at Stanford, before being hired by CU Boulder. Here, she has advanced technology and algorithms for GPS-based positioning, navigation and timing, multipath characterization and correction, and remote sensing using GNSS-based reflectometry and radio occultation measurements.
“I really enjoy being a professor, all aspects of it. Not just teaching. Not just research,” Axelrad said. “I love collaborating with other faculty and I love working with students. I’ve taught my GPS class 25 times, and every year students come in and ask questions no one has asked before. It’s fun and challenging.”
She has served as an advisor or mentor for dozens of graduate and undergraduate students. Current PhD advisee Shaylah Mutschler said she was drawn to Axelrad by both her research and passion.
“I always come away from our meetings feeling energized and even more inspired and motivated than I did going into the meeting. That’s something really special. I honestly don’t know what more I could ask for from an advisor,” Mutschler said.
In addition to her work as a professor, Axelrad served as chair of the aerospace department from 2012-2017, leading it through an era of significant growth that included its naming after longtime benefactors Harold “Joe” and Ann Smead, and the development of a long-planned, dedicated aerospace building, which was completed in 2019.
In 2019, Axelrad was elected into the National Academy of Engineering, one of the highest honors for engineers, for her work on analysis of multipath GPS signals to improve satellite navigation and new approaches to remote sensing.
Axelrad has authored 62 journal papers, 197 conference papers, and served as principal investigator or co-investigator on research grants and contracts totaling $16 million. She recently joined a new research program on campus, Q-SEnSE: Quantum Systems through Entangled Science and Engineering, an interdisciplinary center for quantum science and technology.
“I am just at the very beginning of getting into this new area. I’m hoping to take what I’ve learned in my work with GPS as a starting point for understanding the role quantum sensors could play in future navigation and space systems,” she said.
She is honored to be recognized by the university.
“I feel lucky to be recognized in this way,” Axelrad said. “It’s really humbling given how many amazing faculty there are here at CU Boulder.”