# EM WAVE PROPAGATION AND SCATTERING IN SPATIOTEMPORALLY VARYING MOVING MEDIAThe Exponential Model

### Dan Censor

#### Abstract

An approximate method for analyzing EM wave propagation and scattering in the presence of temporally and spatially varying media is investigated. The method is quasi-relativistic in the sense that for constant velocity it reduces to Einstein’s Special Relativity theory to the first order in the normalized speed v / c . The present exponential model was previously used for temporally invariant velocity only. The motion must be irrotational and the characteristic wavelength and period scales of the mechanical motion must be much larger compared to those of the EM field ones. For simple periodic motion it is shown that the EM field is modulated by the motion, and a spectrum of discrete sidebands is created, with frequencies separated by the mechanical frequencies. The results suggest new approaches to the celebrated Fizeau experiment. Rather than using an interferometer setup as in the traditional experiment, the equivalent phase velocity in a periodically moving medium can be deduced from the measured. Simple examples are computed: the effect of the motion on an initially plane harmonic wave, and scattering by perfectly conducting and refractive planes and cylinders.

#### References

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#### Paper Citation

#### in Harvard Style

Censor D. (2013). **EM WAVE PROPAGATION AND SCATTERING IN SPATIOTEMPORALLY VARYING MOVING MEDIAThe Exponential Model** . In *Proceedings of the Second International Conference on Telecommunications and Remote Sensing - Volume 1: ICTRS,* ISBN 978-989-8565-57-0, pages 62-68. DOI: 10.5220/0004785400620068

#### in Bibtex Style

@conference{ictrs13,

author={Dan Censor},

title={EM WAVE PROPAGATION AND SCATTERING IN SPATIOTEMPORALLY VARYING MOVING MEDIAThe Exponential Model},

booktitle={Proceedings of the Second International Conference on Telecommunications and Remote Sensing - Volume 1: ICTRS,},

year={2013},

pages={62-68},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0004785400620068},

isbn={978-989-8565-57-0},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of the Second International Conference on Telecommunications and Remote Sensing - Volume 1: ICTRS,

TI - EM WAVE PROPAGATION AND SCATTERING IN SPATIOTEMPORALLY VARYING MOVING MEDIAThe Exponential Model

SN - 978-989-8565-57-0

AU - Censor D.

PY - 2013

SP - 62

EP - 68

DO - 10.5220/0004785400620068