Home Anti-Heterodyne Silencer — LMS Active Cancellation Defence (Unit-Tested)

Defensive counter to parametric/heterodyne audio injection: an LMS adaptive canceller detects the injected carrier with an FFT (3014.6 Hz), synthesizes an anti-phase reference, and a 32-tap least-mean-squares filter nulls it to the noise floor (−10.91 dB, carrier bin 512→0) while preserving in-room speech (+1.4 dB). Runnable Python with 5/5 passing unit tests; Three.js visualization of the detection, LMS convergence, waveform cancellation, and FFT peak collapse.

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