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Updated: Jul 23, 2026
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Microwave Photonics Systems Based on Whispering-gallery-mode Resonators
Published on: August 5, 2013
Anomalous pulse delay in microwave propagation: A stochastic process interpretation
A Ranfagni1, R Ruggeri, A Agresti
1Istituto di Fisica Applicata Nello Carrara, CNR, Via Panciatichi 64, 50127 Florence, Italy.
Summary
Superluminal behavior was observed in near-field microwave propagation experiments. Existing models failed to explain these frequency-dependent results, prompting a new stochastic approach.
Area of Science:
- Electromagnetism
- Wave Propagation Physics
Background:
- Microwave propagation in the near-field region is crucial for understanding wave phenomena.
- Previous theoretical models have limitations in explaining complex wave behaviors.
Purpose of the Study:
- To investigate the observed superluminal behavior in near-field microwave propagation.
- To evaluate the adequacy of existing models and propose a new theoretical framework.
Main Methods:
- Experimental setup utilizing two horn antennas for microwave propagation.
- Analysis of wave behavior in the near-field region.
- Development and application of a stochastic model.
Main Results:
- Demonstration of superluminal behavior in microwave propagation.
- Observed strong frequency dependence of the superluminal effect.
- Inadequacy of previously proposed models for interpreting the experimental findings.
Conclusions:
- The observed superluminal behavior necessitates new theoretical interpretations.
- A stochastic model offers a potential framework for understanding these phenomena.
- Path-integral analysis can further refine the proposed stochastic model.
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