The concept of using SAR data to form 3D tomographic images has been developed over the last decade, but the enabling technology has been slow to progress. Current 3D tomographic data gathering techniques require multiple flight passes to gather data at different phase centers. The two technology advancements proposed enabling improvements in the collection of SAR data for ice-sounding and subsurface exploration are compact, multi-band HF/VHF antennas and multi-channel data acquisition systems. Multi-band antennas enable a single antenna to be used over both spectrums most often used for subsurface exploration; their compact design facilitates the placement of multiple antennas on a single platform to enable data collection at multiple phase centers. This advancement is complemented by the development of a multi-channel data acquisition system, which enables the simultaneous collection of data at multiple phase centers. Collecting data simultaneously at multiple phase centers improves data collection by reducing instabilities in measurement locations produced by varying flight paths. Additionally, cost of collection is reduced due the minimization of flight time needed to collect data. Phase I will include the development, fabrication and testing of the antenna system (TRL3 - TRL6), while forming a concept design for the multi-channel acquisition system (TRL1 - TRL2).
