The measured normalized co-polarized and cross-polarized
E-plane and H-plane radiation patterns of the 9-
shaped monopole antenna at 2.45 GHz and 5.2 GHz are
shown in Fig. 5 and Fig. 6 respectively. It can be observed
that the co-polar E-plane radiation pattern is of the shape of
“8” at 2.45 GHz and 5.2 GHz. At 2.45 GHz, the E-plane
cross-polar radiation pattern is in between -10 and -20 dB.
At 5.2 GHz the shape of the co-polar E-plane radiation
pattern is slightly distorted in the bottom right hand side
portion. The co-polar H-plane radiation pattern on the
other hand is purely omni-directional at the two frequencies
i.e. at 2.45 GHz and 5.2 GHz. Unlike at 2.45 GHz, the
H-plane cross-polar radiation pattern is approximately at
around -10 dB or more precisely the H-plane cross polarization
level is in between -10 and -20 dB at 5.2 GHz.
Hence, this 9-shaped monopole antenna demonstrates
a consistent radiation pattern in the desired band of
frequencies.
Fig. 5. Measured E-plane (Co-pol(solid line) and Cross
pol(dotted line)) radiation patterns at (a) 2.45 GHz and
(b) 5.2 GHz.
Fig. 6. Measured H-plane (Co-pol(solid line) and Cross
pol(dotted line)) radiation patterns at (a) 2.45 GHz and
(b) 5.2 GHz.
Fig