Making GPS Receivers Better

An Air Force Office of Scientific Research-funded research team at Ohio State University has developed techniques to increase the accuracy of GPS receivers equipped with anti-jam and adaptive antennas. Led by Dr. Inder Gupta, the team has made breakthroughs in reducing the distortion that these antennas introduce when making positioning and timing measurements, thereby making the receivers more accurate. “A GPS receiver determines its locations by measuring the distance from multiple GPS satellites in view,” explained Gupta. He continued, “The approaches we have developed are very significant because, previously, the receiver’s antenna and associated electronics introduced distortion into the satellite signals that resulted in biases in the distance measurements and affected the accuracy of position and time solution.” AFOSR says this work has direct impact on systems that require precise navigation or geo-location to function such as the joint precision approach and landing system, a portable system similar to an instrument landing system, but that can be set up in 30 minutes in the field to help aircraft avoid rough terrain and enemy forces. (AFOSR report by Maria Callier)