Technical Notes > Radiated Fields > Antenna Parameters
Decay Factor
When Global Environment Material is lossy, strictly
speaking, the far field is zero, since the Green’s function is:
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(1)
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where
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(2)
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Against that fact, HFSS calculates the far field using
the imaginary part of vector k.
You can then modify the magnitude of the field pattern
by using the real part (a) of the propagation
constant, which is displayed as “Decay Factor)