< SWACI Products
Radio Beacons used in SWACI are coherent radio waves at 150 and 400 MHz transmitted by several satellites of LEO-systems such as:
- NIMS (Navy Ionospheric Monitoring Systems)
When computing the differential phase of both signals, the relative, i.e. uncalibrated TEC may be derived. While measuring the signal strength, the scintillation index S4, a measure of signal strength fluctuations, is also estimated.
The reception is performed by the receiver ITS30S which has been especially developed for beacon measurements by Northwest Research Associates, Inc.