Extrapolation of Antenna Near-Field Measurements Using the Iterative Greedy Algorithms

There are often missing gaps in the antenna near-field measurements, due to various physical limitations. However, the missing data are indispensable if we want to accurately evaluate the complete far-field pattern by the near-field to far-field transformations. To address this problem, a fast extrapolation method based on the iterative greedy algorithm is proposed to reconstruct the missing part of antenna near-field measurements in this paper. The near-field data is approximated by sparse signals with the Fourier basis, which is recoverable by the greedy pursuits. As the near-field data in this paper is obtained on the spherical measurement surface, the far field of the antenna is calculated by the spherical near-field to far-field transformation with the extrapolated data. Some numerical results are given to demonstrate the applicability of the proposed scheme in extrapolating antenna near-field measurements.