Direct far-field computation from bi-polar near-field samples

The problem of fast data processing for the bi-polar nearfield measurement technique is addressed in this paper. A computing algorithm is developed to perform direct far-field transformation from near-field samples acquired on the bi-polar scanning surface. Radiation integral is efficiently evaluated by taking advantages of the convolution property leading to use the Fast Fourier Transform and the related shift theorem. The accuracy of the proposed transformation procedure is numerically demonstrated on arrays of infinitesimal dipoles. Results for a measured reflector antenna are also included.