@proceedings {479, title = {e-POP RRI observations of the April 24, 2020 ARRL Frequency Measuring Test}, year = {2021}, month = {03/2021}, publisher = {HamSCI}, address = {Scranton, PA (Virtual)}, abstract = {

One of the science objectives of the Radio Receiver Instrument (RRI) on the CAScade, Smallsat, and Ionospheric Polar Explorer/enhanced Polar Outflow Probe (CASSIOPE/e-POP) satellite is to study ionospheric influences on high frequency (HF) radio wave from low Earth orbit. RRI is made-up of 4, 3-m monopoles which can be electronically arranged into a crossed-dipole configuration.\  On April 24, 2020, RRI tuned to measure the ARRL frequency measuring test (FMT) on 40 m, and successfully recorded part of the {\textquotedblleft}call up{\textquotedblright} and all of the {\textquotedblleft}key down{\textquotedblright} segments of the test.\  The FMT provides a unique chance to study the effects of the ionospheric plasma on stable and reliable radio signals at frequencies that are close to the ionosphere{\textquoteright}s critical frequency, a frequency regime in which the influence of the ionospheric plasma on radio wave propagation conditions is most pronounced.\  In this presentation, we give preliminary results of our analysis of RRI{\textquoteright}s FMT measurements which include an examination of the FMT{\textquoteright}s Doppler characteristics, and the identification tell-tale signatures of ionospheric effects on the transmitted signal such as Faraday rotation and propagation mode delay.

}, url = {https://hamsci2021-uscranton.ipostersessions.com/?s=34-2B-1B-32-C8-FC-4A-0B-5B-51-B9-1D-10-4E-F2-7F}, author = {Brian O{\textquoteright}Donnell and Gareth Perry} }