Full-wave analysis of a compact antenna test range including probe effect

Simulated Quiet Zone (QZ) performance of a designed Compact Antenna Test Range (CATR) is validated by QZ field probing. Numerical simulations of CATRs, however, lack of modeling the probe. The receiving antenna which is used in order to evaluate the field in the QZ has an influence on the calculated / measured co- and particularly, on the cross-polar components. The degree of the probe effect depends on the radiation characteristic and on the cross-polarization purity of the probe. Including the probe into simulations overcomes the disadvantages of probe correction since the possibility exists to calculate arbitrary dimensions of the QZ. In order to determine the extent, probes with varying radiation patterns are characterized and are used during field-probing measurements at a frequency of 4.5 GHz. Subsequently, simulated QZ data is generated using a single-reflector model in combination with the Multi-level Fast Multipole Method (MLFMM) implemented in FEKO. The measured probe patterns are included into the calculated data by applying planar near-field theory on the simulated data. Especially, the cross-polarization changes significantly compared to the original simulation results.