Marietta Scientific, Inc.
The reflection coefficient
G for a thin sheet of ohms/sq. at normal incidences is
where
and the characteristic impedance of free space is
The characteristic impedance for a thin sheet is r in parallel with free space
and r = resistance (ohms/sq.)
Thus the reflection coefficient is:
with
The loss coefficient A is the ratio of the power absorbed in the ohms /sq. to the incident power
where
and
The physical optics current J for ohms/sq. at normal incidence is
where
incident magnetic field and
sheet current (amps/m)
The power absorbed by the ohms/sq. is
Thus the loss coefficient is
or
The transmission coefficient T is the ratio of the power transmitted to the power incident
where
The transmitted and scattering fields are
and
thus
or
Energy is conserved when
Substituting from the above equations
