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This paper describes a methodology for designing feed networks for single-polarized aperture-coupled microstrip patch (ACMP) antennas with dual-offset microstrip feedlines. The method involves characterizing the effective series impedance of the antenna when it is fed in a balanced manner as a function of the distance between the dual feedlines. Fitting equations were generated from the data to relate the effective series impedance to the feed geometry, allowing the design of the matching network for any effective impedance. This work demonstrates that ACMP antennas can be coupled to dual-offset feedlines with λ/4 transformers and T-junctions with infinite combinations of impedance for the λ/4 transformer. A 10 GHz single-polarized ACMP antenna was designed and implemented obtaining satisfactory impedance matching.
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On-Chip Integration of a Plasmonic FET Source and a Nano-Patch Antenna for Efficient Terahertz Wave Radiation
Graphene-based Field-Effect Transistors (FETs) integrated with microstrip patch antennas offer a promising approach for terahertz signal radiation. In this study, a dual-stage simulation methodology is employed to comprehensively investigate the device’s performance. The initial stage, executed in MATLAB, delves into charge transport dynamics within a FET under asymmetric boundary conditions, employing hydrodynamic equations for electron transport in the graphene channel. Electromagnetic field interactions are modeled via Finite-Difference Time-Domain (FDTD) techniques. The second stage, conducted in COMSOL Multiphysics, focuses on the microstrip patch antenna’s radiative characteristics. Notably, analysis of the S11 curve reveals minimal reflections at the FET’s resonant frequency of 1.34672 THz, indicating efficient impedance matching. Examination of the radiation pattern demonstrates the antenna’s favorable directional properties. This research underscores the potential of graphene-based FETs for terahertz applications, offering tunable impedance matching and high radiation efficiency for future terahertz devices.
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- Award ID(s):
- 2011411
- PAR ID:
- 10512951
- Publisher / Repository:
- MDPI
- Date Published:
- Journal Name:
- Nanomaterials
- Volume:
- 13
- Issue:
- 24
- ISSN:
- 2079-4991
- Page Range / eLocation ID:
- 3114
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/nano13243114
