الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
The problems of antenna near field measurements and near field to far field transformation represent an important issue in antenna measurements. However, the difficulty of accurate phase measurements and requirement of complicated measurement setup may represent limitation parameters for antenna near field measurements. This was the motivation to introduce the idea of retrieving the phase data from amplitudeonly near field measurements. This thesis presents four techniques for retrieving the phase distribution of amplitudeonly nearfield antenna measurements on a planar scanning plane. Then, the far field is obtained by using the known amplitudeonly nearfield and the retrieved phase distribution. All these techniques are common in using multiple scalar measurements to retrieve the unknown phase distribution. Numerical results will show good agreement in all these cases between the actual phase distribution and the retrieved one and consequently good agreement between the actual far field and the retrieved far field. However, it will be noted that, to obtain two independent sets of scalar data using the second technique, it is required to use large probes and large scanning planes. This represents another disadvantage of the second technique. It will be also noted that, the results of the phase retrieval based on correlation are more accurate than the corresponding ones obtained by the optimization.