STRETCHABLE ANTENNAS AND RECTENNAS FOR WIRELESS COMMUNICATION AND AMBIENT RF ENERGY HARVESTING
Open Access
- Author:
- Zhu, Jia
- Graduate Program:
- Engineering Science and Mechanics
- Degree:
- Doctor of Philosophy
- Document Type:
- Dissertation
- Date of Defense:
- September 25, 2020
- Committee Members:
- Larry Cheng, Dissertation Advisor/Co-Advisor
Larry Cheng, Committee Chair/Co-Chair
Michael T Lanagan, Committee Member
Mark William Horn, Committee Member
Xin Ning, Outside Member
Judith Todd Copley, Program Head/Chair
Jian Hsu, Committee Member - Keywords:
- Stretchable wideband dipole antennas
Stretchable wideband rectennas
RF energy harvesting
Self-powered systems
Laser-induced graphene-based electronics
Structural design
Wavy serpentine networks - Abstract:
- Bio-integrated electronic devices can pliably conform to the textured skin surface to continuously monitor the physiologically relevant parameters or biomarkers, with a huge impact on human health from preventative monitoring and early diagnostic confirmation to non-invasive and convenient therapeutic options. The ultimate application of this class of emerging electronics hinges on the indispensable modules of stretchable wireless transmission and power supplies. While near field communication (NFC) allows for wireless powering and communication with a working distance of ~ 3 cm, radio frequency (RF) antennas enable wireless transmission of data and energy in the far-field. Materials engineering (i.e., using novel materials with combined superior electrical and mechanical properties, such as nanomaterials and composites) and structural engineering on conventional rigid materials (i.e., employing serpentine, wavy and 3D structures) have been widely used in the design and fabrication of stretchable antennas. Compared to the approaches that exploit stretchable conducting materials such as liquid metal or elastomers with conductive fillers, designing conventional metals in a serpentine or meshed geometry is still of high interest because of their high radiation efficiency. Although this structural design concept has resulted in various stretchable dipole and patch antennas, the limited bandwidth still limits their applications in wireless communication and energy harvesting because of the frequency detuning from mechanical deformations. In this work, we proposed various stretchable structures in the design of stretchable antennas, including patch and dipole, based on conventional materials and found a way to effectively tune the resonance frequency response to external deformations. A large resonance frequency shift to mechanical deformations enables the application in wireless strain sensing, while robust resonance frequency upon stretching promises stable and reliable communication performance. Then, we introduced a stretchable wideband dipole antenna consisting of serpentine units for both main and parasitic arms created by exploiting the laser-induced graphene (LIG) pattern and maskless metal coating. The compensation for the frequency detuning upon deformations helps to further improve the robust electromagnetic properties. Additionally, combining the stretchable dipole antenna with a high-efficiency impedance matching network and rectifying circuit leads to a stretchable rectifying antenna (i.e., stretchable rectenna) that can continuously harvest electromagnetic radiation energies from various widely available RF sources (e.g., WI-FI, 4G, and upcoming 5G). As an added component into the clean energy portfolio for future energy supply, the ambient RF energy-harvesting solution could also contribute to integrated energy systems and enable self-powered systems and remote monitoring of the environment.