WiFoo..The.Secrets.of.Wireless.Hacking [Electronic resources]

Andrew A. Vladimirov

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High-Gain Omni Antennas

The antenna shown in Figure B-8 is a high-gain 12-dBi omni antenna from Mobile Mark Antennas. It is designed with no down tilt for use in long-range communication between sites with similar elevations. If the gain is very high, the antenna has a very narrow vertical beam width resulting in poor performance for indoor applications or those installations where there is a height disparity. An example would be an antenna located on top of a high building, which is intended to provide "local" coverage on the ground.

Figure B-8. 12-dBi Omni Antenna

Table B-6 lists the specification for a typical 12-dBi omni antenna. Note the very narrow vertical beam width.

Table B-6. 12-dBi Omni Specifications

Parameter

Specification

Frequency range

2.42.83 GHz

VSWR

2:1 nominal

Gain

12 dBi

Polarization

Vertical

Azimuth (3-dB BW)

Omnidirectional 360 degrees

Elevation (3-dB BW)

7 degrees

Dimensions

40" * 1.25"

Wind rating

100 mph