Self and mutual admittances of rectangular-slot antennas in the presence of an inhomogeneous plasma layer

The self and mutual admittances for a pair of identical rectangular-slot antennas in an echelon configuration in the presence of an inhomogeneous plasma layer are derived using stationary expressions. Computations using the dominant TE01mode of the waveguide as a trial field are compared with experiments using a wide variety of configurations of space cloth to validate the computational techniques. These self and mutual admittances are then used to calculate the voltage standing-wave ratio (VSWR) and isolation for a pair of rectangular slots in the presence of a typical boundary-layer plasma on a sharp, slender conical body. The number of steps needed to adequately approximate the profile is determined together with the range of validity of various thin and thick sheath approximations.