Abstract:
The classic gain-transfer method assumes a uniform
plane wave incident over the apertures of the gain-transfer standard
(typically a standard-gain horn) as well as the antenna under
test. Variations in the incident field over the quiet zone of an antenna
test range can produce large errors in the estimated gain of
the antenna under test. These errors can be significant, especially
when there is a large difference in aperture dimensions between
the antenna under test and the standard-gain horn. In this letter, a
modified gain-transfer method is described to reduce errors in gain
measurements when antennas significantly larger than the standard-
gain horn are measured in a test range using the gain-transfer
method. The aperture of the antenna under test is usually much
larger than that of the standard-gain horn, and therefore these antennas
will typically be exposed to different variations in the incident
field. Measured results are presented to illustrate accurate
gain measurements for antennas significantly larger than the standard-
gain horn.