GPS Information from the Stanford GPS Lab
The GPS Research Laboratory works with the Federal Aviation Administration, U.S. Navy, U.S. Air Force,
Arinc, NASA and U.S. Coast Guard to pioneer systems that augment the Global Positioning System (GPS) and Galileo. These
augmentations broadcast differential corrections to improve accuracy, provide error bounds in real time, and/or mitigate
radio frequency interference. Specific projects include:
The Wide Area Augmentation System (WAAS) already supports millions of land and marine users
across North America. It became operational for aviation in July of 2003.
Currently, we are working with the FAA to help define the L5 WAAS design. We are researching different options to bring
to the L5 signal as part of the GEAS. The goal is to achieve worldwide LPV-200 approach capabilities.
Briefing on the GNSS Evolutionary Architecture Study (GEAS)
The Local Area Augmentation System (LAAS)
will eventually support automatic landings at high-traffic hub airports.
The Joint Precision Approach and Landing System (JPALS)
will support aircraft landings on aircraft carriers and military air fields.
Technologies that address the vulnerability of satellite navigation to radio frequency interference are of interest. These
include the integration of existing terrestrial radio navigation systems like
Loran - now called enhanced Loran or eLoran. The lab is also very active in the
investigation of software receivers that integrate inertial navigation and adaptive antennas.
Earlier, the laboratory worked with the U.S. Coast Guard to design a medium frequency radio system to broadcast
differential corrections to maritime users of GPS. Today, this system covers much of the world's coastline and
provides differential GPS data to 1.5 million users.
Overview of the Laboratory and Student Research
The Stanford GPS Laboratory, headed by Professor Per Enge, has a staff of professional researchers, over 10 Ph.D.
students as well as graduate students seeking other degrees. For an overview of the Stanford GPS Laboratory,
check out this website and this presentation.
Examples of recent student work are given in the links below.
1) Next generation GNSS, new signals, and signal monitoring. We provide description of the
Galileo code/code generator
derived from data measurements as well as the new
Stanford GNSS Monitor Station (SGMS). Most current information added is on the
GIOVE-B L1 code generator and
GIOVE-B E5 code generator.
2) Controlled Reception Pattern Antenna (CRPA). CRPA antenna technology uses an array of antenna and
signal processing to increase resistance to interference and jamming.
Click here to see a presentation by Ph.D. student David De Lorenzo on his current research in processing
signals from a CRPA.
3) Position Navigation Time (PNT) based Encryption (Geoencryption). Location information can be used to provide a
cryptographic key allowing content to be controlled. Hence decryption can be regulated to occur at specified
locations or times only.
Click here to see a presentation by Ph.D. student Di Qiu on her current research in signal authentication and
Geosecurity: Background and Research
A description of the Compass/Beidou E2 Code from data collected from the SGMS.
GPS Textbook for AA272C Satellite Navigation and AA272D Advanced topics in Satellite Navigation
"Global Positioning System: Signals, Measurements and
Performance", a textbook by Pratap Misra and Per Enge, provides a comprehensive
introduction to GPS.