Title :
Liquid Crystal Tunable mm Wave Frequency Selective Surface
Author :
Hu, Wenfei ; Dickie, Raymond ; Cahill, Robert ; Gamble, Harold ; Ismail, Yusof ; Fusco, Vincent ; Linton, David ; Grant, Norman ; Rea, Simon
Author_Institution :
Queen´´s Univ. of Belfast, Belfast
Abstract :
A frequency selective surface (FSS) which exploits the dielectric anisotropy of liquid crystals to generate an electronically tunable bandpass filter response at D Band (110-170 GHz) is presented. The device consists of two printed arrays of slot elements which are separated by a 130-mum thick layer of liquid crystals. A 3% shift in the filter passband occurs when the substrate permittivity is increased by applying a control signal of 10 V. Measured results show that the insertion loss increases from -3.7 dB to -10.4 dB at resonance (134 GHz), thus demonstrating the potential to create a FSS which can be switched between a transmitting and a reflecting structure.
Keywords :
band-pass filters; frequency selective surfaces; liquid crystals; millimetre wave antenna arrays; permittivity; slot antenna arrays; D band; FSS; dielectric anisotropy; electronically tunable bandpass filter; elements substrate permittivity; filter passband; frequency 110 GHz to 170 GHz; insertion loss; liquid crystal; loss -3.7 dB to -10.4 dB; mm wave frequency selective surface; printed arrays; reflecting structure; slot elements; transmitting structure; voltage 10 V; Anisotropic magnetoresistance; Band pass filters; Dielectric liquids; Frequency selective surfaces; Insertion loss; Liquid crystal devices; Liquid crystals; Loss measurement; Passband; Permittivity measurement; Antennas; filters; frequency selective surface (FSS); liquid crystals; quasi-optics; reconfigurable;
Journal_Title :
Microwave and Wireless Components Letters, IEEE
DOI :
10.1109/LMWC.2007.903455
