Detection of ionospheric perturbations using a dense GPS array in Southern California

[1] We present observations of high-frequency ionospheric perturbations detected using Global Positioning System (GPS) data from the Southern California Integrated GPS Network (SCIGN), a densely spaced GPS array of about 250 stations centered on the Los Angeles area. We show examples of perturbations with 3–10 minute periods that may result from coupling between the ionosphere and neutral gravity waves generated in the lower atmosphere. Although the signal-to-noise ratio of the perturbations is relatively small, we show how multi-station array processing techniques can take advantage of the high spatial density of the measurements and the coherence of the signal over a region the size of the SCIGN to considerably improve the detection capability.