Phase-enhanced trajectory and speed reconstruction of meteoroids using BRAMS data

Abstract

In this project, we aim to reconstruct meteoroid trajectories thanks to a forward scatter radio system using a pure continuous wave (CW) transmitted signal with no modulation. To do so, we use the meteor echoes recorded at the receivers of the BRAMS (Belgian RAdio Meteor Stations) network. The latter is made of a dedicated transmitter and currently 48 receiving stations located in and nearby Belgium, all synchronized using GPS clocks. Our approach processes the signals recorded at the BRAMS receivers and uses the time delays between the meteor echoes as inputs to a nonlinear optimization solver. We compare the quality of our reconstructions data to the trajectories given by the optical CAMS (Cameras for Allsky Meteor Surveillance) network in Benelux. To do so, we solve the general CW forward scatter trajectory reconstruction problem, but we highlight its strong ill-conditioning if the only inputs are the time delays of the echoes at the receivers. To obtain a better accuracy for a large number of meteoroids, the time delays are complemented by information about the signal phase. The approach used for this work is based on the pre-t0 phase technique introduced for backscatter radars. In this project, we extend and adapt the method to forward scatter systems and we illustrate the improved accuracy that it brings on the meteoroid trajectory and speed reconstruction