3Com 3CRWE920G73 Quick Start Manual page 7

Align and Polarize the Units
For optimal performance, position the antenna so that there are minimal obstacles between it and any other antenna with
which it will communicate. While maintaining a direct line of sight between antennas is not strictly necessary, such a
configuration helps to ensure a strong signal. As mentioned earlier, this is not always possible in long distance
configurations.
Any two bridge units that are to communicate with each other must be set for the same polarization, either horizontally or
vertically. If cross-polarization occurs, the link with either work poorly or not at all. Please refer to the ''Polarization''
section of the User Guide for further details. The following illustration shows proper alignment, orientation and
polarization for optimal performance.
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