A Multi-Channel Airborne UHF Radar Sounder System for Oldest Ice Exploration: Development and Data Collection

The Center for Oldest Ice Exploration (COLDEX) project is exploring Antarctica to find a continuous ice record from the present to 1.5 million years ago and document the mid-Pleistocene transition, which occurred ~1 million years ago. The current longest ice record is 800,000 years old. This work describes a new 600-900 MHz UHF radar to help address this challenge with a 1) much larger, 22.8 m or 57-wavelength, cross-track antenna array and 2) higher transmit power, than prior renditions. Survey flights on a Basler aircraft were conducted from the South Pole in 2022-2023 and in 2023-2024. In this work, we provide an overview of the design requirements, the radar system architecture, and antenna array implementation. We also present preliminary results from aerial surveys conducted in Antarctica.