Near field measurements and the synthesis of linear arrays with prescribed radiation patterns: a survey of some early work at Christiaan Huygens Laboratory

An analog complex series analyzer that performs discrete Fourier transform and also solves for the complex roots of the array polynomial equation is described. A planar near-field scan facility, covering the frequency bands from 1.5-40 GHz and featuring a mechanical accuracy of 0.03 mm deviation from a perfect straight line, is also described. Some applications that provide a check on the theory of the analyzer and scanner are discussed. The pros and cons of various near-field measurement methods are compared. It is concluded that, with respect to ease of measurement and correction of the near-field distribution, the planar scan is to be preferred, whereas for overall performance checking, the compact antenna range is useful, although it carries an appreciable cost penalty.<>