Application of split ring resonator (SRR) loaded transmission lines to the design of angular displacement and velocity sensors for space applications
Mata Contreras, Francisco Javier (Universitat Autònoma de Barcelona. Departament d'Enginyeria Electrònica)
Herrojo, Cristian (Universitat Autònoma de Barcelona. Departament d'Enginyeria Electrònica)
Martín, Ferran, (Martín Antolín) (Universitat Autònoma de Barcelona. Departament d'Enginyeria Electrònica)

Date:	2017
Abstract:	The accurate measurement of the angular displacement and velocity of reaction wheels is necessary for attitude (orientation) control in space vehicles (satellites). In this paper, microwave, contactless, and low-cost (as compared to optical encoders) sensors useful for that purpose are analyzed in detail. The sensor consists of a rotor and a stator. The rotor is a disk (or a circular crown) of dielectric material, where one or several arrays of equidistant single-loop split ring resonators (SRRs) are etched along its edge, forming circular chains of hundreds of SRRs. The stator is a coplanar waveguide (CPW) also loaded with pairs of single-loop SRRs (etched in the back substrate side), with the centers located in the slot region. The sensing principle is based on the amplitude modulation of a harmonic (single-tone continuous wave) feeding signal, achieved when the chains of the rotor are displaced over the SRR pairs of the stator. Both sensor elements (rotor and stator) must be parallel oriented, with the SRR pairs of the CPW in close proximity to the SRR chains of the rotor (and rotated 180°), in order to favor their coupling. By this means, the transmission coefficient of the CPW is varied by the circular motion of the rotor, and significant amplitude modulation of the feeding signal is achieved. From the envelope function, the angular velocity can be accurately determined. With the proposed sensors, instantaneous and practically unlimited rotation speeds can be measured.
Grants:	Ministerio de Economía y Competitividad TEC2016-75650-R Ministerio de Economía y Competitividad RTC-2014-2550-7 Ministerio de Economía y Competitividad TEC2013-40600-R Agència de Gestió d'Ajuts Universitaris i de Recerca 2014SGR-157
Rights:	Tots els drets reservats.
Language:	Anglès
Document:	Article ; recerca ; Versió acceptada per publicar
Subject:	Metamaterials ; Split ring resonators (SRRs) ; Microwave sensors ; Angular velocity sensors
Published in:	IEEE transactions on microwave theory and techniques, Vol. 65, issue 11 (Nov. 2017) , p. 4450-4460, ISSN 0018-9480

DOI: 10.1109/TMTT.2017.2693981

Post-print 11 p, 2.0 MB

The record appears in these collections:
Research literature > UAB research groups literature > Research Centres and Groups (research output) > Engineering > CIMITEC-UAB
Articles > Research articles
Articles > Published articles