The use of secondary spatial transforms in near field antenna measurements.

The research detailed in this report was conducted within the near field scanner facility of the DERA at Funtington in West Sussex. The purpose of the research was to increase the capability of the near field antenna measurement system so that the range of antennas that could be accurately tested within the facility could be increased. As no extra funding for the purchase of additional equipment was possible this increase in capability had to be achieved via more experimental and innovative use being made of the existing instrumentation systems. The main aims of the project were to use the availability of the 9 CNC control axes in the system to synthetically increase the extent of the scan plane and subsequently to assess the accuracy of the measurements using a novel statistical interpretation of the nature of the antenna pattern. Both by inspection and via a statistical classification procedure the extent of the accuracy of the measurements was confirmed and the additional error terms associated with the measurement technique identified and assessed