Comparative investigation of methods to reduce truncation errors in partial spherical near-field antenna measurements

This paper presents a comparative investigation of two different but highly suitable techniques for the accurate determination of the full sphere pattern of an antenna from truncated spherical near field measurements. The first approach is based on an iterative procedure which exploits the band-limitedness properties of the radiated field to correctly reconstruct the full sphere data [1]. The second approach was first described in [2] and is based on determining a set of equivalent currents that radiate the same pattern in the known area and thus extrapolate the unknown fields in the truncated area. The comparative study is performed on actual measured near-field data to investigate the effectiveness of each technique in realistic spherical near field antenna measurement scenarios.