First results from the coherent-scatter atmospheric passive radar imager (CAPRI) for passive radio sensing of equatorial plasma instabilities near the Peruvian andes

At equatorial latitudes, near the geomagnetic equator, the detection of coherent scatter echoes from E and F region B-field aligned irregularities (FAI), where the radar k vector is oriented perpendicular to the Earth´s magnetic field (B), is relatively easy. Although, the Jicamarca Radio Observatory (PRO) is extremely useful to study the coherent equatorial low-latitude atmosphere and the systems to which they are coupled, alternatively, the detection of field aligned irregularity (FAI) scattering from “transmitters of opportunity” can be utilized using a passive radar receiver system. This approach to monitoring the ionosphere can operate continuously and be used to provide wide spatial coverage of the unstable ionosphere. Also, utilization of the third party transmitters reduce the cost of the instrument and provides diversity in frequency and scattering geometry.