Fundamentals of Electromagnetic Waves

Diffraction of Electromagnetic Waves

The general method to obtain solutions of the Maxwellian equations from scalar representatives is developed and applied to the diffraction of electromagnetic waves. Kirchhoff’s integral is modified to provide explicit expressions for these representatives. The respective integrals are then evaluated using the method of stationary phase in two dimensions. Hitherto unknown formulae for the polari...

Phs 342 : Electromagnetic Waves

Time reversal of electromagnetic waves.

We report the first experimental demonstration of time-reversal focusing with electromagnetic waves. An antenna transmits a 1-micros electromagnetic pulse at a central frequency of 2.45 GHz in a high-Q cavity. Another antenna records the strongly reverberated signal. The time-reversed wave is built and transmitted back by the same antenna acting now as a time-reversal mirror. The wave is found ...

Non-ionizing electromagnetic waves measurement and monitoring Systems

In this paper, portable and online monitoring systems for non-ionizing EMF measurement, as well as some measurement results in Tehran are discussed. First of all, standards and recommendations related to EMF monitoring, measurement and exposure such as ISIRI No.8567, ICNIRP guideline and ITU-K.83 are reviewed. Then, technical facts and operation of portable device and monitoring station are int...

Universal electromagnetic waves in dielectric

The dielectric susceptibility of a wide class of dielectric materials follows, over extended frequency ranges, a fractional power-law frequency dependence that is called the ‘universal’ response. The electromagnetic fields in such dielectric media are described by fractional differential equations with time derivatives of non-integer order. An exact solution of the fractional equations for a ma...