Prediction of active array impedance from simulator measurements using rounded ramp function interpolation

In order to extend the active reflection coefficient of a phased array to general scan angles from measurements on a multielement phased array waveguide simulator, a new interpolation technique using rounded ramp functions (RRPF´s) is presented. The interpolation formula is tested on an array, simulated by a 25-element simulator, with stripline-fed slots as radiating elements. Contour plots showing the magnitude and the phase of the active reflection coefficient are included. The described interpolation scheme gives a much smoother behavior than a Fourier series expansion published earlier.