Page 149 - Antennas for Base Stations in Wireless Communications

122 Chapter Three

0 0
330 0 30 330 0 30
−10 −10
300 −20 60 300 −20 60
−30 −30
−40 −40
270 90 270 90

240 120 240 120

210 150 210 150
180 180
(a) (b)
0
330 0 30
−10
300 −20 60
−30
co-pol (measured)
−40 x-pol (measured)
270 90
co-pol (simulated)
x-pol (simulated)

240 120

210 150
180
(c)
Figure 3.20 Azimuth plane radiation patterns (f = 0°) of the monopolar antenna at
(a) 1.545 GHz, (b) 2.145 GHz, and (c) 2.745 GHz

3.2.5 Case 5: A Single-Feed Dual-Band
Patch Antenna for Indoor Networks
10
A single-feed dual-band patch antenna is presented in this section.
Similar to the antenna described in Section 3.5.3, this antenna can
also operate in two separate frequency bands across 820–960 MHz
and 1710–2170 MHz, which are the frequencies covering most existing
mobile systems. In order to reduce the interference between the two fre-
quency bands, two low-pass filters are incorporated into the antenna.

3.2.5.1 Antenna Geometry The geometry of the antenna is shown in
Figure 3.21. This antenna consists of two square patches of different
sizes. The smaller patch is mounted on the top of the larger patch in