Spherical Near-Field Scanning With Pointwise Probe Correction

Spherical wave expansion algorithms based on matrix inversion are flexible. They allow arbitrary sampling schemes and higher order probe correction. However, the probe correction technique assumes, up until now, the same measurement probe at every measurement point. This is a limitation, especially for dual-polarized measurement probes and multiprobe measurement systems. In this communication, a spherical near-field (SNF) far-field transformation procedure, including pointwise probe correction, is presented. For a measurement sphere with constant radius, the additional calculation time is small. Furthermore, varying but known measurement distances can be corrected using the same technique. The procedure is tested with a dual-polarized SNF measurement and a simulated measurement with varying measurement distances.