Accurate radiation pattern prediction of phased array antennas using Hadamard based excitations

The radiation patterns of phased array antennas are commonly characterised 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.