Citation: For contributions to the understanding and performance of the new
satellite signals from Galileo and Compass.
Dr. Grace Xingxin Gao has already made truly remarkable contributions to
satellite navigation. Her research is dedicated to the signals and receivers
used by the new Global Navigation Satellite Systems. Grace was the first to
derive the code generators used by the Galileo validation satellites and
the first Compass satellite in medium earth orbit. In December 2005, the
Europeans launched the first prototype satellite for Galileo, called GIOVE-A
. The navigation signals were turned on in January of 2006. Within hours,
Grace worked with others in the laboratory to capture the new civil signals
in three bands. Within weeks, Grace working independently, derived the
underlying algorithms that generate the codes used by GIOVE-A and decoded
the codes in all three frequency bands. Her work was published as part of
the Inside GNSS cover story “GNSS Album: Images and Spectral Signatures of
the New GNSS Signals,” that appeared in May-June 2006. Soon after her
publication, receiver companies around the world implemented her codes and
built prototype receivers to acquire and track the Galileo satellite.
In April 2007, China launched the first medium earth orbiting satellite that
belongs to their Compass system. Using her proven techniques, Grace
demodulated the civil codes broadcast by this M1 satellite in all three
frequency bands (E2, E5b & E6), and proved that all Compass-M1 codes are
Gold codes and derived their code generators as linear shift feedback
registers. She also applied these PRN codes in a software receiver to
acquire and track the Compass-M1 satellite. In April 2008, the Europeans
launched GIOVE-B, which is a pre-production prototype satellite for Galileo.
Grace was the first to discover the underlying code generators.
Grace received her doctorate from Stanford University in September 2008. She
continues to work on the satellite navigation systems as part of a Stanford
research program funded by the FAA. She has presented and published 16 high
quality papers at conferences. In 2007, she was an ION GNSS sponsored
student where her paper won the Best Presentation of the Session.
