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Hier finden Sie wissenschaftliche Publikationen aus den FraunhoferInstituten. Polyhedral sampling structures for phaseless spherical nearfield antenna measurements
 Institute of Electrical and Electronics Engineers IEEE; Antenna Measurement Techniques Association AMTA: Antenna Measurement Techniques Association Symposium, AMTA 2020 : Newport, Rhode Island, USA, 25 November 2020 Piscataway, NJ: IEEE, 2020 ISBN: 9781728198682 ISBN: 9781736235102 S.4550 
 Antenna Measurement Techniques Association (AMTA Annual Meeting and Symposium) <42, 2020, Online> 

 Englisch 
 Konferenzbeitrag 
 Fraunhofer FHR () 
Abstract
The reconstruction of radiation patterns from phaseless nearfield antenna measurements has been investigated using different methods like twosphere techniques, indirect holography, or the use of different probes. Recent research on twosphere techniques introduces algorithms originally developed for phase retrieval, e.g., PhaseLift and WirtingerFlow  applied to Spherical NearField (SNF) measurements, phase retrieval corresponds to obtaining the phase of the Spherical Mode Coefficients (SMCs) from amplitude NearField (NF) measurements only. It has been shown that WirtingerFlow benefits in this case from sample points distributed over distinct structures (two spheres of different size or a sphere and a plane), decreasing the redundancy. Furthermore, it has been shown that increasing the distance between both structures improves the reconstruction of the Far Field (FF). With this work we aim at deepening the above knowledge in the context of spherical wave expansions. From a mathematical point of view, planes can be seen as spheres of infinite radius, i.e., a plane combined with a sphere may be interpreted as a special case of combining two spheres. This interpretation goes hand in hand with the observation that an increased radius difference between two spheres leads to better reconstruction performance. Consequently, we analyze different polyhedral sampling structures composed of planes (such as octahedrons or cubes), mimicking several spheres of infinite radius in different spatial directions. For the mathematical analysis of nonspherical structures in the basis of spherical waves, pointwise probe correction is used. In experiments the polyhedron approach is less influenced by the choice of radii of the single structures compared to the standard twospheres/sphereplane sampling.