Forty years ago today, Rockwell Collins engineer David Van Dusseldorp successfully received and decoded a GPS signal for the first time ever. He sat on the rooftop of a company building in Cedar Rapids, Iowa, adjusting an antenna every five minutes to receive the signal from the world’s first GPS satellite, known as NTS-2. To commemorate this anniversary, Rockwell Collins is hosting retirees involved in the project to share their firsthand stories at an event today in Cedar Rapids.

Soon after Dusseldorp received the signal, the U.S. Air Force awarded Rockwell Collins the Navstar GPS user equipment contract. Since then, the company has continued to pioneer advancements in GPS, such as being the first to complete a transatlantic flight using GPS navigation in 1983.

Compared with the first GPS receiver station which was six feet tall and picked up only one satellite, Collins’s latest GPS-4000S receiver is only 7.87 inches tall (and 2.43 inches wide) and can process the transmissions of up to 10 GPS satellites and two space-based augmentation systems (SBAS) geostationary satellites simultaneously. Collins also makes a Micro GPS Receiver Application Module that is only one inch tall, can use data from up to 12 GPS satellites and consumes the least power of any receiver in its class.

Since that historic day 40 years ago, Rockwell Collins has introduced more than 50 GPS products and delivered more than one million GPS receivers for commercial avionics and government applications.