Correction for Probe-Position Errors in Planar, Near-Field Scanning

摘要

In recent years, near-field antenna measurement techniques have gained a good deal of acceptance. There are several errors in the computed far-field patterns caused by measurement inaccuracies in the near-field data. These paper deals with deterministic errors introduced by probe-positioning errors in planar, near-field scanning. By utilizing basic near-field theory, as well as a knowledge of the positioning errors, it is possible to estimate the fields at the correct probe position. A computer program which lessens the effect of probe positioning errors by means of a truncated Taylor series expansion is used to demonstrate this improvement. To simulate inaccurate probe positioning, a database of calculated near-field values for a linearly polarized, uniformly illuminated, circular aperture was used. Next, the position correction program was applied to computer generated inaccurate data. Finally, far-field patterns were calculated, and compared using both the corrected and uncorrected data. Results of the comparisons are presented. Limitations, and areas of application of this routine are discussed. (Theses)