Antarctic ice shelf 3D cross sectional profile imaging using MIMO radar

Observation of the thickness of Antarctic ice shelves is vital for predicting the rise in sea levels caused by melting of the world´s largest fresh water reservoir. This paper proposes a ground-based radar system using a MIMO phased array antenna layout to accurately monitor thickness changes and provide 2 dimensional cross-range information of the ice shelf. The radar system used to collect data is a Step Frequency (SFCW) Radar using multiple transmitting and receiving antennas which operate orthogonally in time. The MIMO antenna layout is shown together with the beam pattern from the associated virtual array. The aperture synthesis of the MIMO array using digital beamforming technique is discussed. Results of the aperture synthesis, showing the cross-range and depth profile of the ice shelf to be observed will be shown. The study conducted using the MIMO antennas is part of a future plan to replace the SFCW Radar system with an FMCW system that will allow long term deployments to observe variability in the rate of change of the ice shelf thickness. One of the conclusions of the paper is that a linear version of the MIMO array will make more efficient use of the antennas than a 2D version of the array.