This tool simulates the full receive chain for an Earth-Venus-Earth (EVE) radar experiment — from TX burst through free-space propagation to the received echo. It models the IQ waterfall that an SDR would capture, with correct noise statistics, Doppler chirp, and rotational broadening.
Echo: Monostatic radar — you transmit, signal bounces off the target, you receive the reflected return. FSPL is 2×one-way. RCS determines return power.
Beacon: Target has its own transmitter (e.g., a spacecraft). One-way path only. No RCS — just EIRP and receive gain.
TX burst starts at t=0. The echo arrives after the round-trip light time RTT = 2×R/c. For Venus at 42 M km, RTT ≈ 280 s. The waterfall shows the full timeline from TX through echo arrival.
The echo frequency drifts linearly at the configured drift rate (Hz/s). Coherent integration is limited by this chirp — τ_max = √(RBW/drift). The waterfall shows the drifting tone as a diagonal stripe.
The CAMRAS preset uses measured data from the Dwingeloo 25m + Stockert 25m EVE experiment on 2025-03-22. RTT = 279.975 s, Doppler = +411.68 Hz, drift = −0.2269 Hz/s. Use to validate your setup.