Diffraction is simply explained as bending of waveforms. There is a possible of bending of waveforms and such bending is known as diffraction. All propagating waves such as electromagnetic wave, waves in water, sound wave etc forms diffraction.
KNIFE EDGE DIFFRACTION:
A portion of the incident radiation that strikes an obstacle like mountain range and edge of the building is redirected by the radiation and this radiation is called as knife edge radiation. This diffraction is in the waveforms is caused by an edge of any top or tip. Thus this type of diffraction is known as knife edge diffraction.
Formula – Knife Edge Diffraction:
Knife Edge Diffraction is simply knotted as KED as short form. The diffracted wave from a knife edge is the solution of perpendicular and parallel polarizations. This is for the radio wave propagation when the polarization or composition is unknown. The Knife Edge Diffraction is termed for a semi infinite half plane between a point source and also an observation point. A line which is drawn from the source to the observation point will clear the diffracting knife edge with a distance d. The below shown formula states the solution for the knife edge diffraction.
Here k is represented as wave number.
The secondary wavelet is the source of wavelet on each point. A new wavelet is produced in the direction of propagation and this wavelet is called as secondary wavelet.
The amplitude rises and fall linearly in the knife edge with a function that can be approximated for v>-0.7
Figure – Knife Edge Diffraction:
The signal amplitude of the knife edge diagram is used to calculate the diffraction of knife edge diffraction. This signal is shown in the graph below.
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