Anomaly distinguishability in an asteroid analogue using quasi-monostatic experimental radar measurements

TL;DR

This paper evaluates the effectiveness of quasi-monostatic radar measurements combined with advanced filtering and tomography techniques to distinguish topography and interior structures of asteroid analogues, demonstrating the importance of wavefield data.

Contribution

It introduces a novel approach combining travel-time and wavefield backpropagation tomography with PCA filtering to improve asteroid analogue distinguishability.

Findings

Wavefield information improves reconstruction quality across noise levels.

Different filters influence distinguishability depending on noise and structure assumptions.

Main signal peaks can effectively identify topography and interior structure.

Abstract

This study conducts a quantitative distinguishability analysis using quasi-monostatic experimental radar data to find a topographic and backpropagated tomographic reconstruction for an analogue of asteroid Itokawa (25143). In particular, we consider a combination of travel-time and wavefield backpropagation tomography using the time-frequency representation (TFR) and principal component analysis (PCA) approaches as filtering techniques. Furthermore, we hypothesise that the travel time of the main peaks in the signal can be projected as a topographic imaging of the analogue asteroid while also presenting a tomographic reconstruction based on the main peaks in the signal. We compare the performance of several different filtering approaches covering several noise levels and two hypothetical interior structures: homogeneous and detailed. Our results suggest that wavefield information is vital for obtaining an appropriate reconstruction quality regardless of the noise level and that different filters affect the distinguishability under different assumptions of the noise. The results also suggest that the main peaks of the measured signal can be used to topographically distinguish the signatures in the measurements, hence the interior structure of the different analogue asteroids. Similarly, a tomographic reconstruction with the main peaks of the measured signal can be used to distinguish the interior structure of the different analogue asteroids.