FDTD Analysis of the Sagnac Effect Employed in the Global Positioning System
Mohammad Marvasti, Halim Boutayeb
Abstract
This communication proposes a full-wave analysis of the Sagnac effect by using a direct finite-difference time-domain (FDTD) approach, where the source, observer, and dielectric medium are moving. The Sagnac effect is employed in the global positioning system (GPS) to obtain the correct location of a receiver. This effect occurs on the downlink time, joining a satellite and the receiver, due to the rotation of the Earth. Different numerical analyses are carried out with the FDTD method, by using, for example, an air-filled metallic ring waveguide or a ring microstrip line. For problems that include a moving dielectric medium, a technique for the implementation of Fresnel–Lorentz drag effect is proposed. The obtained results agree with the experiments reported in the literature. This work has potential applications for the design of electromagnetic gyroscopes.