Open Radar Code Architecture (ORCA): A Platform for Software-Defined Coherent Chirped Radar Systems

Ice-penetrating radar systems are critical instruments for observing the subsurface conditions on Earth's ice sheets. Traditionally, ice-penetrating radars have not been widely accessible to the glaciological community (as in the case of resource-intensive airborne systems) and/or have been limited in their ability to be reconfigured and optimized for studying different glaciological targets (as in the case of hardware-defined radar systems). To alleviate the challenges associated with this situation, we have developed the Open Radar Code Architecture (ORCA), which is an open-source radar software codebase that allows commercially available software-defined radios (SDRs) to be used as coherent ice-penetrating radars. Here, we describe the architecture of our code, characterize coherence on SDR-based radars, and demonstrate techniques we use to improve SNR and overall performance. We also highlight the variety of SDR options available to potential users and discuss tradeoffs between different system configurations.