Optical antenna using D-fibre for radio-over-fibre applications

Abstract

Finite element analysis has been used to characterize an all-fibre antenna using circular core D-fibre. The optical D-fibre carrying a transversely poled piezoelectric polyvinylidene fluoride (PVDF) polymer coating was modeled by using three-dimensional stress analysis. The response of the D-fibre antenna was determined over a wide frequency range from 1 to 700 MHz. The modeling predicts that the electric field induced strains will cause a phase shift of 2.43 × 10-5 rad/(V/m) per metre at 5 MHz. At frequencies higher than 8 MHz the optical response is dominated by radial resonances of the D-fibre/coating composite. Using the simulation results, an electric field induced phase shift of 7.35 × 10-5 rad/(V/m) per metre has been obtained. An increase in phase modulation sensitivity by a factor of three compared to conventional circular fibre has been achieved by utilizing the unique properties of the D-fibre structure. The D-fibre antenna has potential applications in areas such as EMC testing and radio-over-fibre networks where it provides a convenient means of optically generating radio signals. © 2002 Elsevier Science (USA). All rights reserved.