Software-defined radar (SDRadar) has been proposed as a cost-effective approach to implementing radar systems with high reconfigurability. Many processes of a radar system that were traditionally implemented in analog hardware, such as filtering and mixing, can now be performed in the digital domain. We have developed a next-generation software-defined radar based on the Xilinx Radio Frequency System-on-Chip (RFSoC) platform, which integrates an ARM CPU, an FPGA, and multiple high-speed data converters on a single chip. This platform is used to implement the SDRadar transceiver.
Multistatic radars utilize spatial diversity by having multiple monostatic and bistatic configurations. They are capable of measuring backscatter and forward scatter at different angles, enabling multi-angle observations. With this capability, multistatic radars have received much attention, especially in environmental monitoring applications.
However, several challenges hinder the widespread use of multistatic radar systems. One major challenge is the requirement for clock synchronization (coherency) between different nodes. Additionally, accurate localization of each radar node is necessary for correct measurement interpretation. Another significant challenge is the calibration of multistatic polarimetric radar systems. The lack of suitable passive calibration targets for wide frequency bands in bistatic configurations, along with the added complexity of dual polarization channels, makes calibration much more difficult than in monostatic single-polarized systems.
We are developing techniques in all three of these areas, synchronization, localization, and calibration, to establish a network of UAS-based SDRadars that can be deployed for various environmental monitoring applications.
