Accurate Radiation Pattern Prediction of Phased Array Antennas Using Hadamard-Based Excitations

The radiation patterns of phased array antennas are commonly characterized through embedded element patterns, wherein only one element is excited for each measurement at a time. However, this approach is suboptimal as it does not reflect the typical operation of a fully active array. To address this limitation, a Hadamard matrix based-method is proposed that uses orthogonal measurements of the fully excited array to derive single element patterns. This method provides a superior representation of the radiation properties of the fully active antenna array and its mutual coupling effects, while providing measurements with a greater signal-to-noise ratio. The element patterns from embedded elements and the Hadamard method are evaluated and used to predict beamforming patterns using over-the-air measurements.