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A circular polarized (CP) pentaband antenna based on the aperture-in-aperture (AIA) concept is presented for CubeSat applications. This AIA consists of five different bands ranging from L-band to Ka-band. Four different antennas, each operating at a specific frequency band, namely 12 GHz, 18.5 GHz, 26 GHz, and 32 GHz, were incorporated into an L-band (viz. 1.5 GHz) antenna. Notably, the five antennas can operate simultaneously for a CubeSat downlink operation with a frequency ratio of 21.3:1. The antenna structure shows a realized gain of 5–10 dBi with good CP bandwidth (< 3 dB) across the overall operational frequency range. That is, the realized gain of L-band (1.5 GHz), X-band (12.5 GHz), K-band1 (18.5 GHz), K-band2 (26 GHz), and Ka-bands (32 GHz) are 5.05 dBi, 8.21 dBi, 7.33 dBi, 7.97 dBi, and 8.56 dBi. A high impedance surface (HIS) is incorporated with the Ka-band antenna to mitigate the ripples in the radiation pattern created by the interference of surface waves. A prototype was fabricated and tested. The measurement data agrees well with the simulation.
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Robotically‐controlled antenna measurement system for millimeter‐wave applications
Abstract The characterization of antenna radiation patterns in millimeter‐wave (mmW) bands can be particularly challenging. Due to a small wavelength, minute misplacement of the probe antenna in the order of few millimeters can generate substantial errors in the measured pattern. A highly precise measurement system that incorporates a 6‐axis compact robotic arm is implemented to overcome this challenge. System testing shows a positional accuracy and repeatability of approximately 20 μm or 0.004λ at 60 GHz. After implementation, programming, and testing, the system is used to measure gain patterns on three different mmW antennas. The radiation pattern of a 50–75 GHz standard gain horn antenna demonstrated the accurate measurement at the far‐field using the robotically controlled system. Furthermore, the characterization of the center element pattern of a 60 GHz phased array has shown that the measurements with this system are repeatable and suitable for arrays as well. Additionally, we performed near‐field measurements by successfully characterizing a 40–60 GHz horn antenna with a planar scan.
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- Award ID(s):
- 1711102
- PAR ID:
- 10452138
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Microwave and Optical Technology Letters
- Volume:
- 63
- Issue:
- 5
- ISSN:
- 0895-2477
- Page Range / eLocation ID:
- p. 1520-1525
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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