Nokia RoofTop R240, User Manual

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24 Nokia RoofTop™ Wireless Router Installation Guide
Directional antennas - radiation pattern side view
In Nokia Wireless Router Networks, use a directional antenna only if:
• There are numerous obstructions in the area
• The nearest router is a considerable distance away
• The router is in a location where it does not need to route traffic for
other subscribers and itself requires a maximum link distance to the
neighboring router.
3.1.2.4 Notes on antenna polarization
Polarization refers to the direction of antenna element alignment. For
antennas to properly communicate with each other, all antenna must be
aligned (polarized) in the same direction.
• Omnidirectional antenna
This vertically polarized antenna can only be mounted vertically.
• Directional antenna
• Polarization is identified by an arrow on the rear panel
• Radiates from the front side and away from the mounting bracket
• Can be vertically or horizontally polarized
If you have a combination of vertical omnidirectional antennas and
directional antennas, the directional antennas must be polarized vertically.