Logan Scott receives Kepler award

Institute of Navigation’s (ION) Satellite Division awarded Logan Scott its Johannes Kepler Award on September 12, 2025, during the ION GNSS+ 2025 conference in Baltimore, Maryland, for sustained contributions to satellite navigation signal design, recognition and mitigation of interference and spoofing threats to GPS, and advocacy for civil GNSS assurance.

Logan Scott’s seminal contributions to satellite navigation over his 45+ year career include digital receiver design; early recognition of threats to GPS from interference and spoofing; invention of location-based encryption, “J911” crowd-sourced geolocation of interference sources; and use of cryptographic signal authentication for civil radionavigation signals.

Scott was a key technical leader in pioneering receiver designs at Texas Instruments, including signal acquisition and tracking, adaptive arrays, jamming, and fade resistance. In 1985, Logan and his team developed the world’s first all-digital GPS receiver, paving the way towards the low-cost, compact, lightweight, and energy efficient receivers now numbering in the billions.

Scott was the first to describe methods for civil signal authentication. He invented a new and fundamental delayed-key asymmetric navigation security paradigm now embodied in the GPS Chimera signal, next generation WAAS, and Galileo systems; and he participated in the creation of the Chimera authentication signal.

Scott discovered and described how an adaptive array can bias phase and pseudorange measurements to adversely affect high precision receivers; particularly how such biases could cause Real Time Kinematic (RTK) ambiguity resolution to fail. This work became essential to the success of the Joint Precision Approach and Landing System (JPALS) program.

Since 2015, Scott has been a core member of the NTS-3 Advanced Signals Team, originating multiple signal design concepts, at least nine of which will be tested on-orbit. His signal designs focus on civil signal assurance, optimization of the navigation data message by leveraging concepts from the communications industry, and advanced waveforms to enhance military receiver performance.

As a member of the U.S. National PNT Advisory Board, Scott promoted the need and methods for resilient and robust PNT, and required spectrum protection. In 2010-2011 he developed and quantified the performance of crowdsourced interference detection and geolocation using cell phones.

ion.org