20 GHz Antenna Radiation Pattern Obtained From Near-Field Mapping With Electrooptic Probe on a Single Plane

• Published in: IEEE antennas and wireless propagation letters Vol. 19; no. 7; pp. 1177 - 1181
• Main Authors: Gaborit, Gwenael, Artillan, Philippe, Bermond, Cedric, Revillod, Guillaume, Chevrier-Gros, Guillaume, Duvillaret, Lionel
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.07.2020; The Institute of Electrical and Electronics Engineers, Inc. (IEEE); Institute of Electrical and Electronics Engineers
• Subjects: <named-content xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:ali="http://www.niso.org/schemas/ali/1.0/" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" content-type="math" xlink:type="simple"> <inline-formula> <tex-math notation="LaTeX"> Ka</tex-math> </inline-formula> </named-content>-band; Antenna gain; Antenna measurements; Antenna radiation pattern; Antenna radiation patterns; Antennas; Aperture antennas; Apertures; Computer simulation; Confidence intervals; electric field mapping; Electric fields; Electromagnetic radiation; Electromagnetism; Electronics; electrooptic (EO) sensor; Electrooptic modulators; Engineering Sciences; Far fields; Horn antennas; Mapping; Micro and nanotechnologies; Microelectronics; near-field sensing; Probes; Spatial resolution
• ISSN: 1536-1225; 1548-5757
• DOI: 10.1109/LAWP.2020.2994263

The ability of an electrooptic (EO) sensor to perform near-field mapping of a 20 GHz pyramidal horn antenna without disturbance on the radiation behavior is demonstrated. The electric field is scanned on a plane close to the horn aperture with spatial resolution less than <inline-formula><tex-math notation="LaTeX">\boldsymbol {0.1\lambda _0}</tex-math></inline-formula>. The dynamic range reaches more than 40 dB. The measured magnitudes and phases of near-field pixels enable the computation of the far-field radiation pattern. The results are in excellent agreement with theory, numerical simulations and actual far-field measurement. The different approaches lead to the same antenna gain with a confidence interval lower than 1 dB. Furthermore, the behavior of the electromagnetic wave from reactive to radiative region is investigated. The weak invasiveness of the probe is also analyzed.