National Aeronautics and Space Administration

Glenn Research Center


The ACTS Propagation Campaign began in 1994 and provided 5 years of site dependent propagation measurements at K and Ka bands at 7 different locations across the North American subcontinent. These sites were chosen due to their accessibility and unique climatological zones (see Figure 1 below).  The primary purpose of the propagation campaign was in the development of a global model to define expectations for atmospheric-induced propagation losses for future ground segment site selection at Ka-band frequencies.

  • Fairbanks, AK
  • Vancouver, BC
  • Fort Collins, CO
  • Las Cruces, NM
  • Norman, OK
  • Clarksburg, MD
  • Tampa, FL
ACTS Climatological Zone Site Map

Map of locations of ACTS propagation campaign ground stations, overlayed onto climatological map delineated by rain rate zones.

Beacon signals from the ACTS satellites at 20.185 GHz and 27.5 GHz provided direct attenuation measurements, in tandem with radiometric observations at similar frequencies.  By collecting propagation  data at various climates (rain rate zones) throughout the US, the data collected from the ACTS propagation campaign led to global propagation models for satellite system design and performance analysis, still in use today.

For ACTS-related publications, see the ACTS website.