  We present a particle-level model for calculating the radio scatter of
incident RF radiation from the plasma formed in the wake of a particle shower.
We incorporate this model into a software module ("RadioScatter"), which
calculates the collective scattered signal using the individual particle
equations of motion, accounting for plasma effects, transmitter and receiver
geometries, refraction at boundaries, and antenna gain patterns. We find
appreciable collective scattering amplitudes with coherent phase for a range of
geometries, with high geometric and volumetric acceptance. Details of the
calculation are discussed, as well as the implementation of RadioScatter into
GEANT4. A laboratory test of our model, currently scheduled at SLAC in 2018,
with the goal of measuring the time-dependent characteristics of the reflecting
plasma, is also described. Prospects for a future in-ice, high-energy neutrino
detector, along with comparison to current detection strategies, are presented.
