Sensors (Apr 2024)

Harmonic FMCW Radar System: Passive Tag Detection and Precise Ranging Estimation

  • Ahmed El-Awamry,
  • Feng Zheng,
  • Thomas Kaiser,
  • Maher Khaliel

DOI
https://doi.org/10.3390/s24082541
Journal volume & issue
Vol. 24, no. 8
p. 2541

Abstract

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This paper details the design and implementation of a harmonic frequency-modulated continuous-wave (FMCW) radar system, specialized in detecting harmonic tags and achieving precise range estimation. Operating within the 2.4–2.5 GHz frequency range for the forward channel and 4.8–5.0 GHz for the backward channel, this study delves into the various challenges faced during the system’s realization. These challenges include selecting appropriate components, calibrating the system, processing signals, and integrating the system components. In addition, we introduce a single-layer passive harmonic tag, developed specifically for assessing the system, and provide an in-depth theoretical analysis and simulation results. Notably, the system is characterized by its low power consumption, making it particularly suitable for short-range applications. The system’s efficacy is further validated through experimental evaluations in a real-world indoor environment across multiple tag positions. Our measurements underscore the system’s robust ranging accuracy and its ability to mitigate self-interference, showcasing its significant potential for applications in harmonic tag detection and ranging.

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