An improved method for simultaneous calibrations of gain, phase center and near boresight patterns for Log-Periodic Dipole Arrays

A novel approach is presented for calibration of the gains, phase center locations and near boresight antenna patterns of Log Periodic Dipole Arrays. The measurement procedure mirrors the standard site method for calibrating low gain antennas, which is conducted over a PEC ground plane in an Open Area Test Site (OATS). In both methods, one of antennas is set at a fixed height, and the other is scanned over 1 to 4 m in heights. In the standard site method, only the maximum response during the height scan is preserved. In the proposed method, responses versus height are kept and are fitted to a theoretical model using a complex fit algorithm. Unlike the standard site method, where the phase center is assumed stationary, and patterns are assumed dipole-like, the new approach makes no such assumptions. Instead, they are formed as unknowns, which are solved along with the antenna gains. With the proposed method, not only did we achieve gains with reduced measurement uncertainties, but also obtained other valuable antenna parameters, including the phase center locations and pattern information.