All-optical bandwidth-tailorable radar

TL;DR

This paper presents an all-optical, reconfigurable radar system that uses a single laser source and optical heterodyning to generate wideband, tunable radar signals, enhancing detection capabilities and resolution.

Contribution

It introduces a novel all-optical radar architecture with bandwidth and frequency agility, utilizing wavelength-to-time mapping and optical heterodyning for improved performance.

Findings

Successfully demonstrated bandwidth-tunable radar signals

Achieved significant time-stretching and frequency compression of echoes

Enhanced radar detection and resolution capabilities

Abstract

Radar has been widely used in military, security, and rescue. Metamaterial cloak is employed in stealth targets to evade radar detection. Hence modern radar should be reconfigurable at multi-bands for detecting stealth targets, which might be realized based on microwave photonics. Here, we demonstrate an all-optical bandwidth-tailorable radar architecture. It is a coherent system utilizing one mode-locked laser for both signal generation and reception. Heterodyning of two individually filtered optical pulses that are pre-chirped via wavelength-to-time mapping generates wideband linearly-chirped radar signal. The working bands can be flexibly tailored with desired bandwidth at user-preferred carrier frequency. After modulated onto the pre-chirped optical pulse, radar echoes are time-stretched and frequency-compressed by several times. The digitization becomes much easier without loss of detection ability. We believe that the demonstration can innovate the radar's architecture with ultra-high range resolution.