# 2-D Coherence Factor for Sidelobe and Ghost Suppressions in Radar Imaging

## TL;DR

This paper introduces a 2-D coherence factor for radar imaging that combines spatial and frequency diversity to effectively suppress sidelobes and ghosts, improving image quality.

## Contribution

A novel 2-D coherence factor method that enhances sidelobe and ghost suppression by integrating frequency diversity with spatial coherence.

## Key findings

- Improved sidelobe suppression in radar images.
- Enhanced imaging quality in both cross-range and range directions.
- Validated performance through simulations and experiments.

## Abstract

The coherence factor (CF) is defined as the ratio of coherent power to incoherent power received by the radar aperture. The incoherent power is computed by the multi-antenna receiver based on only the spatial variable. In this respect, it is a one-dimensional (1-D) CF, and thereby the image sidelobes in down-range cannot be effectively suppressed. We propose a two-dimensional (2-D) CF by supplementing the 1-D CF by an incoherent sum dealing with the frequency dimension. In essence, we employ both spatial diversity and frequency diversity which, respectively, enhance imaging quality in cross range and range. Simulations and experimental results are provided to demonstrate the performance advantages of the proposed approach.