User's Manual

AR24027 Operator’s Manual (rev E)
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3 ANTENNAS, SITE SELECTION, PATH ANALYSIS
3.1 Introduction
NOTE
Basic instructions for connecting the antenna to the radio are given in
section 4. If the system is to be used at short to moderate ranges and
there are no major obstructions between antennas, the more detailed
information in this section may not be necessary.
Because AR24027 radios communicate with each other by means of radio waves, all aspects of
antenna installation affect their performance significantly, namely:
• antenna type used
• clear line-of-sight path between antennas
• antenna orientation
• antenna placement
• antenna-to-antenna distance between radios
• distance between the radio and its antenna (antenna cable length)
Therefore antenna installation is a vital part of system installation. Improper installation may greatly
reduce system performance, possibly rendering the system inoperable.
This section discusses these issues and provides guidelines for selecting antenna type, selecting
antenna location, and achieving an optimally functioning installation.
3.2 Selecting Antenna Type
There are a vast number of antenna types designed for various general and special purposes, but
despite the huge variety, all designs essentially address two concerns, directionality and gain. These
selection criteria are discussed in the following paragraphs, along with a third criterion, polarization.
For the AR24027, the three antenna types listed below will fulfill most installation requirements.
Antenna Type Gain AFAR Model Number
Omnidirectional 9 dBi ATO-2409-000
Panel 18 dBi ATD-2418-000
Semi-Parabolic 24 dBi ATD-2424-000