Near-field alignment of phased-array antennas

This paper describes the algorithms and equipment used to apply near-field scanning techniques to the phase alignment of phased-array antennas. This procedure achieves a level of precision not previously available. The electronic scanning property of the antenna is used to bring different sections of the antenna spectrum within range of the near-field scanning process. These partial spectra are then merged to define the entire spectrum of the antenna. This process provides the resolution needed to determine the excitation at individual elements by the inverse Fourier transformation operation. The process described here has been used in the production of a very large number of phased-array antennas currently in service.