Key aspects of robot based antenna measurements at millimeter wave frequencies

In this paper important aspects concerning a probe based antenna characterization environment for frequencies up to 325 GHz are described. The flexibility to measure the far-field antenna diagram and to perform a near-field sampling is achieved by use of an industrial robot. In advance to the complete measurement setup verification, two main aspects of the new system are investigated. For the measurement of an antenna radiation pattern the receiving frequency converter is moved around the probe station with the Antenna Under Test (AUT). Therefore, the cables carrying the intermediate frequency signal are also in motion. The impact on the accuracy of the results is shown. Moreover an antenna gain calibration technique with a 3S-standard (three Shorts) for the probe deembedding and its precision are discussed.