@inproceedings{584f0c5a36c44b50a324a8c62cbc229b,
title = "Near-field measurements of submillimeter-wave reflectarrays",
abstract = "We present results of experimental characterization of static 650-GHz reflectarrays. The reflectarrays are based on 123-µm circular microstrip patch antennas with tuning stubs as phase shifters. The static reflectarrays are considered as predecessors for active reflectarrays, and therefore the reflectarray elements have two discrete phase-shift values: 0° and -180°. The reflectarrays have 95000 elements, and they have separation of 400 µm. The reflectarrays are fabricated on 150-mm silicon wafers with a ground plane and a 20-µm polyimide substrate atop. The fabricated static reflectarrays are characterized in a near-field measurement range and their beam patterns at the focusing distance of 20 m are calculated with plane-to-plane transform. At this high frequency, fabrication tolerances are difficult to meet and, e.g., over-etching of the antenna and phase-shifting structure may offset the resonance frequency of the reflectarray element by more than its bandwidth.",
keywords = "imaging radar, near-field measurements, reflectarray, submillimeter-wave",
author = "Aleksi Tamminen and Juha Ala-Laurinaho and Sampo M{\"a}kel{\"a} and {Gomes Martins}, David and Janne H{\"a}kli and P{\"a}ivi Koivisto and Pekka Rantakari and Jussi S{\"a}ily and Reijo Tuovinen and Arttu Luukanen and Markku Sipil{\"a} and R{\"a}is{\"a}nen, {Antti V.}",
year = "2013",
doi = "10.1117/12.2018606",
language = "English",
isbn = "978-0-8194-9506-8",
series = "Proceedings of SPIE",
publisher = "International Society for Optics and Photonics SPIE",
editor = "Wikner, {David A.} and Luukanen, {Arttu R.}",
booktitle = "Passive and Active Millimeter-Wave Imaging XVI",
address = "United States",
note = "SPIE Defense, Security, and Sensing 2013 ; Conference date: 29-04-2013 Through 03-05-2013",
}