Normally in the conductor free electrons are present due to which we have electric fields and if these are moving we also have the magnetic fields around the conductor. These electric and magnetic fields are responsible for the wave to propagate.normally we observe it in the case of antenna propagation,when antenna is fed by the current source due to charge and as this charge is flowing we have electric and magnetic fields which help in wave propagation.we have many types of antenna's in the past like yagi-uda antenna which has a dipole for which the current is fed,in this antenna another two parasitic elements are present called directors and reflectors. reflector is used to reflect back the back side radiation(opposite to the wave propagation) directors are used to place the radiation in the desired direction.we also have reflector antennas,horn antenna,microstrip antenna(mostly used in mobile phones),helical antenna and many more designing up.But the principle remains same.
The antenna height is determined by the wave frequency.if the wave is of smaller frequency it requires very long antenna(since wavelength is inversly proportional to frequency) and if the wave has higher frequency we can easily transmit,but due to tech development we developed some modulation techniques to transmit the wave having lower frequency.
Suppose assume that wave is propagating along x-axis,then we have the electric and magnetic fields in perpendicular direction to x-axis that is it may be along y or z-axes.In the direction of propagation we dont have any types of fields.further if electric field is along is y-axis,it will be independent of 'y' but is a function of 'x'.similarly if magnetic field is along z-axis,it will be independent of 'z' but will be function of 'x'.
Based on the maxwell's equations we can decide the nature of wave in the charge ,free and conducting region.The nature of the EM waves vary from medium to medium and also upon the angle of incidence whether it is oblique or normal incidence.
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The antenna height is determined by the wave frequency.if the wave is of smaller frequency it requires very long antenna(since wavelength is inversly proportional to frequency) and if the wave has higher frequency we can easily transmit,but due to tech development we developed some modulation techniques to transmit the wave having lower frequency.
Suppose assume that wave is propagating along x-axis,then we have the electric and magnetic fields in perpendicular direction to x-axis that is it may be along y or z-axes.In the direction of propagation we dont have any types of fields.further if electric field is along is y-axis,it will be independent of 'y' but is a function of 'x'.similarly if magnetic field is along z-axis,it will be independent of 'z' but will be function of 'x'.
Based on the maxwell's equations we can decide the nature of wave in the charge ,free and conducting region.The nature of the EM waves vary from medium to medium and also upon the angle of incidence whether it is oblique or normal incidence.
