An Efficient Total Radiated Power Test Method Based on Optimal Interpolation Over a Sphere of Large Antenna Array

In this paper, an optimized interpolation method is proposed to improve the efficiency of total radiated power (TRP) testing in anechoic chamber (AC). First, from electromagnetic information theory, it is known that the antenna radiation field can be accurately approximated on the observation sphere using finite samples more than the spatial degree of freedom (DoF). The spatial DoF of an antenna under test (AUT) is proportional to its electrical size. Then, the relationship between the maximum allowable sampling interval and the AUT's DoF is developed based on the spherical wave expansion theory. Finally, the TRP is obtained based on a small number of samples (slightly larger than the DoF). Simulations verifies the effectiveness of the proposed method.