Characteristics of cw signals propagated under the ice in the Arctic

Envelope statistics and tonal spectra have been measured from 15, 20, and 30-Hz cw signals propagated via an ice-covered path over a range of approximately 300 km. These data were taken during the TRISTEN/FRAM II experiment on the pack ice over the Pole Abyssal Plain in April/May 1980. Five hours of data are analyzed. The received signals were very stable in time and exhibited only minor fluctuations due entirely to the in-band noise. The envelope amplitude statistics are Rician. Though the source and receiver were on drifting ice floes, the drift rates were negligible during transmission periods and thus these results apply to transmissions between essentially fixed terminals.