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Updated: Jul 13, 2025
13:44
Simulation, Fabrication and Characterization of THz Metamaterial Absorbers
Published on: December 27, 2012
15.4K
Reducing Non-Through Body Energy Transfer in Microwave Imaging Systems
Peter Serano1, Johnathan W Adams1, Louis Chen1
1Worcester Polytechnic Institute, Worcester, MA USA 01609.
Summary
This study introduces metal-backed RF absorbing foam to improve microwave imaging (MI) systems. The foam significantly reduces signal loss around the body, enhancing the signal-to-noise ratio (SNR) for clearer imaging.
Area of Science:
- Biomedical Engineering
- Electromagnetics
- Medical Imaging
Background:
- On-body antennas in microwave imaging (MI) systems can lead to signal degradation.
- Energy directed around the body, rather than through it, lowers the signal-to-noise ratio (SNR).
Purpose of the Study:
- To introduce and quantify the effectiveness of metal-backed RF absorbing foam.
- To mitigate signal loss caused by around-body energy propagation in MI systems.
- To improve the overall SNR of on-body antenna-based MI systems.
Main Methods:
- Numerical simulations using Ansys HFSS to model the system.
- Experimental validation using a helmet prototype with embedded antennas.
- Quantification of RF absorbing foam's impact on antenna coupling and SNR.
Main Results:
- Metal-backed RF absorbing foam significantly reduces around-body coupling.
- A reduction of approximately 10dB in coupling was observed for Transmit (Tx) and Receive (Rx) antennas.
- Simulations and experimental measurements showed consistent results.
Conclusions:
- Metal-backed RF absorbing foam is an effective, low-cost solution for improving MI systems.
- This method substantially enhances the SNR by reducing unwanted signal pathways.
- The principle is applicable to various body parts for diverse MI applications.
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