High impedance surfaces are regularly used as ground planes for low-profile antennas, but popular design methods don’t capture the detuning effects that occur when the antenna and surface are designed separately, then placed in proximity. HIStrip is a transmission-line based circuit model that accounts for near-field interaction between a planar antenna and its high-impedance surface ground plane.

S. Soltani, J. Dusenbury and K.C. Kerby-Patel, “An Approximate Multiconductor Transmission Line Model for an Antenna Loaded by High-Impedance Unit Cells,” in IEEE Transactions on Antennas and Propagation, vol. 67, no. 6, pp. 4133-4140, June 2019.

K.C. Kerby-Patel, “Transmission Line Model For Microstrip Line Above a Periodic High-Impedance Surface Ground Plane,” Proc. Antenna Applications Symp., Monticello, IL, Sept. 2013