An ice-penetrating software-defined radar has been developed that operates with a chirp frequency of 140–160 MHz and 20 W of output power. The system was designed to be compact, portable, flexible, and adaptable to future project goals. Commercial-off-the-shelf components were used where possible to ensure a short development time and a cost-effective approach with the modular PXI platform. A software-defined radio approach was employed, using sub-Nyquist sampling to downconvert the return signal to baseband. Hardware coherent signal integration and real-time matched filtering operations are accomplished using the system’s Virtex-5 FPGA.
The system is simulated using Agilent’s SystemVUE simulation software to evaluate system power levels across the transmitter, glacier, and receiver signal paths. Network analyzer measurements were made on the components to confirm simulation with physical system response. The system was coded and integrated in a manner such as to allow for modifications to be made in the future to allow porting of system capabilities to other needed tasks. Component selection is reviewed as well as ice electromagnetic properties relevant to the work conducted here.