Reconstruction and Estimation of Scattering Functions of Overspread Radar Targets

TL;DR

This paper demonstrates the theoretical possibility of reconstructing the scattering function of overspread radar targets using a single sounding with a custom delta train, and proposes an estimator for cases with incomplete statistics.

Contribution

It introduces a method to identify the scattering function of overspread targets from full statistics and develops an estimator for partial information scenarios.

Findings

Theoretically possible to identify scattering functions with complete statistics.

Proposed an estimator as a replacement for the averaged periodogram.

Applicable when the scattering function's support area is less than one.

Abstract

In many radar scenarios, the radar target or the medium is assumed to possess randomly varying parts. The properties of a target are described by a random process known as the spreading function. Its second order statistics under the WSSUS assumption are given by the scattering function. Recent developments in the operator identification theory suggest a channel sounding procedure that allows to determine the spreading function given complete statistical knowledge of the operator echo. We show that in a continuous model it is indeed theoretically possible to identify a scattering function of an overspread target given full statistics of a received echo from a single sounding by a custom weighted delta train. Our results apply whenever the scattering function is supported on a set of area less than one. Absent such complete statistics, we construct and analyze an estimator that can be used as a replacement of the averaged periodogram estimator in case of poor geometry of the support set of the scattering function.