Experimental VSWR's and radiation patterns of an axial rectangular slot on conducting cylinders of varying curvature

X
band measurements of the VSWR's and radiation patterns of an axial rectangular slot on six conducting cylinders of different curvature are reported. The cylinders had
k_{0}a
(
k_{0}
is the free-space wavenumber and
a
is the cylinder radius) varying from
\infty
to 1.5. Measurements were performed both with the slot bare and with the slot covered by space cloth. For
k_{0}a
as low as 3, the effect of curvature was relatively small. Below
k_{0}a \simeq 3
, changes in the VSWR and radiation pattern were more pronounced, the pattern being relatively more sensitive to changes in
k_{0}a
than the VSWR.