Preliminary Beacon Total Electron Content (TEC) and Scintillation Measurements during the 2019 Probing Regions via Ionospheric Modification (PRIM) Campaign

One of the goals of the 2019 PRIM campaign was to look for TEC enhancements along the Earth's magnetic field lines generated by the Arecibo high-power HF facility. The HF facility at Arecibo in Puerto Rico was used to modify the ionosphere while simultaneously, a ship, the USNS Waters carrying numerous diagnostics was located north of Puerto Rico. Two satellites, the Canadian CASSIOPE/ePOP and the US DMSP-F15 overflew the region more than 30 times while operating beacons broadcasting coherent pairs at 150.012 MHz (VHF) and 400.032 MHz (UHF). Earth-based receivers use this pair of frequencies for measuring TEC and scintillations along the propagation paths. An advantageous geometry is possible using ship-based receivers at Arecibo. The ship location was chosen so that three satellite passes (2 by DMSP-F15 and 1 by CASSIOPE/ePOP) would have a propagation path directly along the Earth's magnetic field and through the region of the ionosphere modified by the high-power HF during the satellite trajectory. This experiment was motivated by large TEC increase seen in the 2014 measurements over the HAARP HF facility using the CASSIOPE/ePOP beacon when in a similar geometry, i.e., when the propagation path was along the Earth's magnetic field. Other PRIM satellite passes yielded information on background ionospheric conditions, such as the presence of Traveling Ionospheric Disturbances (TIDs) in the region. We will discuss preliminary results from several receivers based both on the USNS Waters and at Arecibo.

This work was sponsored by the Naval Research Laboratory Base Program.