Effect of field amplitude taper on measured antenna gain and sidelobes

Amplitude taper of the field of a pattern measurement range produces gain and sidelobe values lower than the true values. A calculation is made using one-parameter distributions, for which the gain can be found in closed form, thereby avoiding the errors in previous calculations. For small tapers both gain errors and sidelobe level errors are linearly proportional to taper (dB). These results are useful in the design of pattern ranges, especially for very low sidelobe antennas, where the amplitude taper is more critical.