Bat Doppler Shift Compensation

Horseshoe bats hunt using long constant-frequency echolocation calls tuned precisely to an "acoustic fovea" in their inner ear — but their own flight speed Doppler-shifts every returning echo upward, threatening to push it out of that narrow band of peak sensitivity. This simulation renders a bat and a moving moth in 3D and computes the real two-leg Doppler formula for a bounced signal, letting you control the bat's closing speed and the target's speed independently. With Doppler Shift Compensation switched on, the bat continuously retunes its outgoing call frequency so the echo always lands back on its 83 kHz reference frequency; switch it off to watch the echo frequency drift with flight speed instead, exactly the problem real CF-FM bats solve every time they give chase.