The polar cusp and boundary layer are important in coupling magnetospheric energy sources to the high latitude ionosphere. ULF waves are one of the processes by which this coupling is realized. To study the source regions and propagation characteristics of discrete Pc1‐2 (0.1–2 Hz) ULF wave packets, particularly unstructured emissions and Pc1 bursts at high latitudes, a triangular array of closely spaced induction magnetometers (∼150 km) was deployed beneath the average cusp projection during the 1992 Antarctic winter. From interstation time lags the wave velocity and direction of arrival were calculated with average uncertainties of ±60 kms−1and ±8°. Wave sources were poleward of the array at low geomagnetic activity and equatorward at high activity. The sources also moved east to west with time, centred around local noon. These results are interpreted as indicative of the ionospheric signature of sources localized in the cusp, the low latitude boundary layer (LLBL) or the outer magnetosphere. Intercalibration of the results for typical events with extrapolations of PACE radar observations and DMSP satellite particle signatures support sources within these regions. Observed group velocities in the range 300–800 kms−1with a mean of 450 kms−1are consistent with wave propagation in the ionospheric waveguide. Signals above the waveguide lower cutoff frequency likely propagate away from the source in the ionospheric waveguide and across the magnetometer array. The results suggest a technique for monitoring the high latitude boundary regions and outer magnetosphere using local ULF w
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