GeometryTuneESA.zip contains relevant data to the publication referenced below. File contents are as follows: PetalAntennaTune_Measured/Sim.opj: OriginLab file containing measured/simulated data from prototype antenna. PetalGainPolarization.opj: OriginLab file containing simulated gain, radiation pattern, and polarization results from simulation. /SimFiles: This folder contains CST 2014 files used to simulate the antenna design to extract tuning range, gain, and radiation patterns. For more information regarding this data please refer to the following publication: Esser, B., Mankowski, J. J., Dickens, J. C., & Neuber, A. A. ( 2019). Geometry Tuning of an Electrically Small Antenna for Ionospheric Heating. Radio Science, 54. https://doi.org/10.1029/2018RS006785 It is requested that the above publication be referenced should this test data should be used.