What does a Gaussian-clutter radar twin promise about detection, not just false alarms?

What it found

With CA- and OS-CFAR thresholds set in a Gaussian twin and deployed in gamma-textured clutter, the exact false-alarm and detection laws (including a new one-dimensional OS-CFAR law) match simulation to ~1%. OS-CFAR is inflated much like CA (design 1e-4, ν=2: 30× vs 35×). Repairing the threshold costs 3.7–4.6 dB, yet the SNR needed for Pd = 0.9 at Pfa = 1e-4 is 6.3 dB above the twin’s promise at ν=2 (2.8 dB at ν=5, 0.8 dB at ν=20), and at the twin’s own threshold and promised SNR real Pd is 0.84 while Pfa is 30× design. Texture does not reverse the CA-beats-OS ranking (a negative result). Stylised: iid gamma texture, constant-SNR target, no interferers, no real radar data.

A figure from its own output

Paper, code and results

• README and method
• White paper
• Experiments and results
• Code
• Tests

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Produced with AI assistance (Claude). Results are from the code in this repository and are simulated or stylised unless the abstract says otherwise; nothing here implies affiliation with or endorsement by any lab, researcher or company cited. MIT licensed.