Mode Conversion of Radar Waves in Meteor Plasmas for Remote Sensing applications

Billions of meteoroids enter our atmosphere daily, forming plasma that is detectable by ground-based radar. Radar data contains information on meteoroid velocity, mass, density, and orbital elements. Typically, radar pulses reflect off plasmas when the natural frequency of the plasma exceeds that of the pulse. In a nonuniform plasma the incoming radar pulse can be absorbed and converted into an electrostatic wave mode supported by the plasma in a phenomenon called mode conversion. Theory has predicted how an incoming vertically polarized electromagnetic wave of oblique incidence angle is absorbed by a 1D parabolic density gradient. Should there be evidence of mode conversion in radar returns, the plasma temperature could be reliably determined from first principles for meteors observed at lower altitudes (80-90 km) with radars operating at VHF (30-300 MHz). The objective of this study is to determine the influence of mode conversion in radar returns using Particle-In-Cell simulations and determine a method for inferring plasma observables.