Portable Passive Radar: Aircraft and Meteorite Detection

The provided text offers a comprehensive technical assessment of portable and highly sensitive passive radar systems, specifically for aircraft and meteorite detection. It begins by defining passive radar's reliance on "Illuminators of Opportunity" (IoOs) like broadcast signals rather than dedicated transmitters, highlighting its covert operation and lower costs but also challenges like complex signal processing and dependence on uncontrolled external sources. The document then explores the fundamental principles, including bistatic/multistatic geometry and system architecture, before examining various IoO types and their suitability, emphasizing trade-offs between sensitivity, resolution, and portability. Significant attention is paid to achieving high sensitivity through hardware and interference/clutter mitigation techniques, noting the conflict between these requirements and portability constraints on Size, Weight, and Power (SWaP). Finally, the text addresses application-specific challenges for aircraft (including stealth and UAVs) and meteorites (due to extreme velocities and plasma effects), concluding with future trends and recommendations for developing such complex yet advantageous systems.