CaESAR - Integrated Radar and Electronic Surveillance (ES) system

Unmanned Air Systems (UAS) pose an immediate and growing threat to the public at large and to US DoD installations and personnel around the world. The Army’s counter UAS (C-UAS) systems use radar and electronic surveillance (ES) to detect, locate, track, and classify UAS threats. Radar is used to establish precise 3D location of multiple UAS systems, while ES is used to correctly identify a UAS. However, these two systems are often employed as separate systems rather than one integrated system; this separation misses a significant opportunity to optimally leverage ES and radar data in the C-UAS kill chain. The key bottleneck in the C-UAS kill chain is the system operator’s positive threat ID decision, which can be delayed if ES classification information is not fused correctly to a corresponding radar track. Numerica proposes CaESAR (Combined Electronic Surveillance and Radar), a novel software-defined radio (SDR) platform with a single dual-polarized broadband antenna aperture capable of S-band radar and wideband (WB) direction-finding ES. CaESAR is designed to measure angle-of-arrival for any UAS transmission between 400 MHz and 6 GHz to support ES-to-radar data correlation. The wide operating bandwidth required for ES is enabled through commercial-off-the-shelf (COTS) wideband transceiver chips and element-level digital beamforming (DBF). The SDR platform supports detection, classification, tracking, resource management, and other radar/ES processing tasks through a heterogeneous (FPGA, GPU, CPU) processing architecture. ES mode and radar mode mutually utilize a single broadband antenna aperture and identical analog and digital circuitry, differing only in firmware/software. ES-to-radar data correlation is enabled through Numerica’s TRL-9 multiple frame assignment (MFA) composite tracker, which is demonstrated in a field test successfully fusing passive ES angle measurements on a UAS to a corresponding 3D radar track. CaESAR integrates ES and radar into a single system, which when paired with ES-to-radar data correlation provides an integrated threat picture – a key force amplifier to accelerate the C-UAS kill chain timeline when integrated with a weapon system.