The ISIS 2 (International Satellites for Ionospheric Studies) Swept-Frequency Sounder measured the ionospheric electron density in the altitude range 300 to 1400 km, and provided correlative data for the other ISIS 2 experiments, particularly those measuring ionospheric parameters. The ionosonde was a radio transmitter that recorded the time delay between a transmitted and returned radio-frequency pulse. A continuum of frequencies between 0.1 and 20 MHz was sampled every 14 or 21 s, and one of six selected frequencies was also used for sounding for a few seconds during each 14- or 21-s period. In addition to the sweep- and fixed-frequency modes of operation, a mixed mode was available in which the transmitter frequency was fixed at one of six possible frequencies while the receiver swept. Several virtual-range (delay-time) traces resulting from ground reflections, plasma resonances, birefringence of the ionosphere, nonvertical propagation, etc., were normally observed.
Version:2.1.0
The ISIS 2 (International Satellites for Ionospheric Studies) Swept-Frequency Sounder measured the ionospheric electron density in the altitude range 300 to 1400 km, and provided correlative data for the other ISIS 2 experiments, particularly those measuring ionospheric parameters. The ionosonde was a radio transmitter that recorded the time delay between a transmitted and returned radio-frequency pulse. A continuum of frequencies between 0.1 and 20 MHz was sampled every 14 or 21 s, and one of six selected frequencies was also used for sounding for a few seconds during each 14- or 21-s period. In addition to the sweep- and fixed-frequency modes of operation, a mixed mode was available in which the transmitter frequency was fixed at one of six possible frequencies while the receiver swept. Several virtual-range (delay-time) traces resulting from ground reflections, plasma resonances, birefringence of the ionosphere, nonvertical propagation, etc., were normally observed.
| Role | Person | StartDate | StopDate | Note | |
|---|---|---|---|---|---|
| 1. | PrincipalInvestigator | spase://SMWG/Person/James.H.Whitteker |
Information about the Swept-Frequency Sounder on ISIS 2