Ultra wideband (UWB) technology plays a significant role in wireless communication. The
complex antenna transfer function (CATF) of an UWB antenna provides important
information required for better channel designs and communication systems. In this
dissertation the CATF of a Double ridge guide horn (DRGH) antenna is determined and
used as a standard antenna for UWB measurements. Two methods were used: the two
antenna method in an anechoic chamber and a modified gain-transfer method in a compact
antenna test range (CATR). Measurements were performed with a vector network analyser
(VNA) in the frequency domain, in the anechoic chamber and the CATR. The distance
measurements required to calculate the CATF from the S-parameter measurements were
performed in the time domain. The CATF of the standard antenna was determined using
two identical antennas and then it was shown that a modified gain-transfer method can be
used to determine the CATF of any unknown antenna in a CATR, using the standard
antenna as a reference. Some of the challenges were to obtain the correct equations and
measurement method to obtain the CATF in a CATR. The standard antenna was used to
investigate uncertainty contributions for the measurements in the CATR.
Dissertation (MEng)--University of Pretoria, 2013.
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