- Award ID(s):
- Publication Date:
- NSF-PAR ID:
- Journal Name:
- 2019 IEEE International Symposium on Antennas and Propagation and USNC-URSI Radio Science Meeting
- Page Range or eLocation-ID:
- 1527 to 1528
- Sponsoring Org:
- National Science Foundation
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We present an analysis of graphene-loaded transmission line switches for sub-millimeter wave and terahertz applications. As such, we propose equivalent circuit models for graphene-loaded coplanar waveguides and striplines and examine the switching performance under certain parameters. Specifically, we identify the optimum design of graphene switches based on transmission line characteristic impedance, scaling factor, graphene shape, and topology (series or shunt). These parameters are varied to obtain the insertion loss and ON/OFF ratio of each switch configuration. The extracted results act as the design roadmap toward an optimum switch topology and emphasize the limitations with respect to fabrication challenges, parasitic effects, and radiation losses that are especially pronounced in the millimeter wave/terahertz bands. This is the first time that such an in-depth analysis is carried out on graphene-loaded transmission line switches, enabling the development of efficient millimeter wave/terahertz tunable topologies in terms of insertion loss and ON/OFF ratio. Specifically, the optimized switches can be integrated with antennas or employed for the development of tunable phase shifters, leading to the implementation of efficient reconfigurable reflective surfaces (e.g., reflectarrays) or coded phased arrays either for imaging or wireless communication applications. In our models, we use measured graphene values (sheet impedance) instead of theoreticalmore »
High-performance graphene-integrated thermo-optic switch: design and experimental validation [Invited]
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A low cost millimeter-wave (mm-wave) electronically reconfigurable Reflect Array (RA) has been presented in this paper. Aperture-Coupled Patch (ACP) elements are used to forma 40×40 element reconfigurable RA operating in the 71-74 GHz range of the mm-wave band. A feeding network, integrated with Single-Pole, Single-Throw (SPST) switches is designed to adjust the phase of the reflected field for the ON/OFF state of the switch. The performance of the reconfigurable RA is evaluated by performing beam focusing at the near-field of the array.
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