Gain Calibration of a Horn Antenna Using Pattern Integration

A cooperative program between the Jet Propulsion Laboratory and the National Bureau of Standards will result in the gain measurement of a horn antenna using three different techniques: a two-antenna insertion loss measurement, a pattern integration method, and a near-field measurement method. This article describes the application of the pattern integration method and also the evaluation of the near-field gain correction factors for the horn, which are determined by a new method based directly on measured data. The method involves a spherical wave expansion of the experimental radiation pattern of the specific antenna being tested, rather than evaluation of an assumed analytical model. The spherical wave expansion is also compared to experimental near-field pattern data. The gain of the antenna is determined by the pattern integration method to be 22.02 dB within a 3<r tolerance (or 99.7% confidence interval) of ±0.1 dB. It is concluded that the pattern integration method is a valuable technique with a potential of even better accuracies with further development. JPL TECHNICAL REPORT 32-1572 vii Gain Calibration of a Horn Antenna Using Pattern Integration