X‐Band Photonics Radar System for Autonomous sUAV Target Parameter Estimation Using Micro‐Doppler TF Analysis

ABSTRACT Microwave‐photonics technology enables advanced radar systems by leveraging high bandwidth and low‐loss signal processing for enhanced target detection and tracking. This paper presents the design and implementation of an X‐band photonics‐assisted continuous wave radar system, specifically developed for the detection and parameter estimation of small unmanned aerial vehicles (sUAVs) using micro‐Doppler time‐frequency analysis. The system incorporates a novel image‐based processing algorithm that extracts critical rotor characteristics, such as rotational speed, blade length, and tip velocity. A detailed link‐budget and hardware configuration, including intermediate frequency signal parameters, low‐noise amplifier range, and analog‐to‐digital converter specifications, are presented to support system performance evaluation. Extensive open‐field experiments were conducted on multiple real‐time targets—including two‐blade, three‐blade, and flapping‐wing sUAV models—with varying tilt angles and ranges up to 75 m. The system demonstrated the ability to detect up to four simultaneous targets, with a measurement accuracy ranging from 91.8% to 99%. This study contributes a scalable radar architecture and robust detection framework for security‐critical applications, such as drone surveillance, reconnaissance detection, and autonomous threat tracking.