The Very High Frequency (VHF) Band & Space Weather

Radio Band	Uses
VHF Band Frequencies: 30-300 MHz (1 MHz = 1,000,000 Hz = 1 million wave cycles per second)	TV ( 54-88 MHz and 174-216 MHz) FM Radio (88-108 MHz)
Wave Paths	Effects of Space Storms
Usually line-of-sight transmission is used (which covers at most ~100 km depending on the power of the transmitter). These frequencies pass through the ionosphere and can be uplinked to communications satellites for retransmission to distant receivers. Ionospheric conditions have little impact.	For Satellite-to-Ground Communications: Signal quality is affected by irregularities in the ionosphere which produces phase and amplitude variations in the received signal. Irregularities are enhanced, particularly at polar latitudes, during space weather disturbances.

Radio Band

Uses

VHF Band
Frequencies: 30-300 MHz
(1 MHz = 1,000,000 Hz = 1 million wave cycles per second)

TV ( 54-88 MHz and 174-216 MHz)
FM Radio (88-108 MHz)

Wave Paths

Effects of Space Storms

Usually line-of-sight transmission is used (which covers at most ~100 km depending on the power of the transmitter). These frequencies pass through the ionosphere and can be uplinked to communications satellites for retransmission to distant receivers. Ionospheric conditions have little impact.

For Satellite-to-Ground Communications: Signal quality is affected by irregularities in the ionosphere which produces phase and amplitude variations in the received signal. Irregularities are enhanced, particularly at polar latitudes, during space weather disturbances.

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