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Pneumatically-Actuated Liquid Metal-Based Frequency Reconfigurable Antenna
Yiwen Song1, Aditya Bharambe2, Dinesh K Patel2
1Department of Electrical and Computer Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA, 15213, USA.
Advanced Science (Weinheim, Baden-Wurttemberg, Germany)
|December 13, 2025
Summary
This study introduces a stretchable liquid metal antenna that maintains high efficiency across a wide frequency range (1-5 GHz). This innovative antenna technology overcomes limitations of traditional rigid antennas for software-defined and cognitive radios.
Area of Science:
- Electrical Engineering
- Materials Science
- Antenna Theory
Background:
- Software-defined radios (SDRs) and cognitive radios (CRs) require antennas capable of wide frequency reconfiguration.
- Existing antennas are either narrow-band with high efficiency or wide-band with low efficiency, limiting SDR/CR performance.
- A practical, high-efficiency, wide-range frequency-reconfigurable antenna is needed.
Purpose of the Study:
- To present a novel soft, stretchable, compact, omnidirectional liquid metal composite antenna system.
- To enable high radiation efficiency across a wide frequency band (1-5 GHz) for reconfigurable antennas.
- To integrate hardware optimization with a software control algorithm for automatic optimal signal reception.
Main Methods:
- Optimized an extendable multi-branch stretchable liquid metal antenna geometry for high efficiency across frequencies.
- Developed a control algorithm for automatic antenna configuration to optimal received signal strength.
- Experimental characterization of the antenna's performance under strain and across the operating frequency range.
Main Results:
- The liquid metal antenna system (PASTA) demonstrates high radiation efficiency when reconfiguring frequencies.
- Achieved a strain limit of 33% for two independent actuatable branches.
- Reduced radiation loss by 10-20 dB compared to state-of-the-art rigid and flexible antennas over the 1-5 GHz range.
Conclusions:
- The developed stretchable liquid metal antenna overcomes limitations of traditional antennas for SDRs and CRs.
- PASTA offers a practical solution for high-efficiency, wide-range frequency-reconfigurable antennas.
- This technology enables improved performance for adaptive radio systems.
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