HF Antenna Array Characterisation Using a Multi-Copter Platform

Abstract

The Super Dual Auroral Radar Network (SuperDARN. is an international collaboration of researchers interested in Earth’s near-space plasma environment. This group uses 35 high frequency (HF. radars and backscatter from magnetic field-aligned plasma irregularities to measure the Doppler Velocity of the ionosphere in order to study Space Weather manifested in the Earth’s magnetic field (magnetosphere. and ionosphere. The movements of these irregularities are tied to the magnetic reconnection of the Earth's magnetic field with the solar wind of the interplanetary medium. The SuperDARN radar uses a 16-element Twin Terminated Folded Dipole (TTFD. phased array to transmit and receive 300us/100us pulses at up to 2.4 kW per antenna over a frequency range between 8 MHz and 20 MHz. One of the challenges of such a physically large array is that it is very difficult to characterize the beam shape and pointing direction using traditional, far-field techniques. The approach is expensive, logistically demanding and in most cases results in inaccurate and sparse data. Advances in multi-copters have unlocked many new and exciting applications for scientific research. One such application is the possibility of characterising large arrays such as the SuperDARN radar. This project proposes that a near-field measurement of a SuperDARN array, using a multi-copter platform, and a near-to-far-field transformation can be used to characterize the far-field beam patterns. A near-field scan on the SuperDARN would involve the multi-copter flying in a vertical plane around 30 m, or farther, in front of the array. Additionally a second vertical plane scan would be needed around 30 m farther than the first plane. This allows for much simpler, phase-less measurements, where the phase can be de-embedded by a plane-to-plane transform. - Abstract as displayed in the - Abstract booklet. The presentation on the day may differ from the - Abstract.