# Design of robust radar detectors through random perturbation of the target signature

## TL;DR

This paper proposes a novel radar detection method that enhances robustness to target signature mismatches by introducing a random perturbation model, maintaining performance under ideal conditions while improving mismatch resilience.

## Contribution

It introduces a new robust radar detector design using random target signature perturbations, extending Kelly's detector with adjustable robustness levels without performance loss in matched scenarios.

## Key findings

- Proposed detectors achieve increased robustness to target signature mismatches.
- Detectors maintain Kelly's detector performance under matched conditions.
- Different complexity and robustness levels are achievable with the new approach.

## Abstract

The paper addresses the problem of designing radar detectors more robust than Kelly's detector to possible mismatches of the assumed target signature, but with no performance degradation under matched conditions. The idea is to model the received signal under the signal-plus-noise hypothesis by adding a random component, parameterized via a design covariance matrix, that makes the hypothesis more plausible in presence of mismatches. Moreover, an unknown power of such component, to be estimated from the observables, can lead to no performance loss. Derivation of the (one-step) GLRT is provided for two choices of the design matrix, obtaining detectors with different complexity and behavior. A third parametric detector is also obtained by an ad-hoc generalization of one of such GLRTs. The analysis shows that the proposed approach can cover a range of different robustness levels that is not achievable by state-of-the-art with the same performance of Kelly's detector under matched conditions.