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Hier finden Sie wissenschaftliche Publikationen aus den FraunhoferInstituten. A Compressed Sampling for Spherical NearField Measurements
 Annual Symposium of the Antenna Measurement Techniques Association, AMTA 2018. Proceedings : 4th  9th November 2018, Williamsburg, United States Piscataway, NJ: IEEE, 2018 ISBN: 9781728112909 Art. 18401770, 6 S. 
 Antenna Measurement Techniques Association (AMTA Annual Meeting and Symposium) <40, 2018, Williamsburg/Va.> 

 Englisch 
 Konferenzbeitrag 
 Fraunhofer FHR () 
Abstract
Spherical nearfield measurements are regarded as the most accurate technique for the characterization of an Antenna Under Test's (AUT) radiation. The AUT's farfield radiation characteristics can be calculated from the Spherical Mode Coefficients (SMC), or spherical wave coefficients, determined from nearfield data. The disadvantage of this technique is that, for the calculation of the SMC, a whole sphere containing the AUT must be Nyquistsampled, thus directly implying a longer measurement time when only a few cuts are of interest. Due to antennas being spatially bandlimited, they can be described with a finite number of SMC. Besides, the vector containing the SMC can be proved sparse under certain circumstances, e.g. if the AUT's radiation pattern presents information redundancy, such as an electrical symmetry with respect to coordinate system of the measurement. In this paper, a novel sampling strategy is proposed and is combined with compressedsensing techniques, such as basis pursuit solvers, to retrieve the sparse SMC. The retrieved sparse SMC are then used to obtain the AUT's farfield radiation. The resulting farfield pattern is compared for both simulated and measured data. The reduced number of points needed for the presented sampling scheme is compared with classical equiangular sampling, together with the estimated acquisition time. The proposed sampling scheme improves the acquisition time with a reasonable error.