Align Antennas

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5. Check the LED on top of the power injector to be sure that
power is being supplied to the wireless bridge through th e
Ethernet connection.
Align Antennas
After wireless bridge units have been mounted, connected, and
their radios are operating, the antennas must be accurately
aligned to ensure optimum performance on the bridge l inks. This
alignment process is particularly impor tant for long-range
point-to-point links. In a point-to-multipoint configuration the
Master bridge uses an omnidirectional or secto r antenna, which
does not require alignment, but Slave bridges still need to be
correctly aligned with the Master bridge antennna.
•Point-to-Point Configurations – In a point-to-point
configuration, the alignment process requires two people at
each end of the link. The use of cell phones or two-way radio
communication may help with coordination. To start, you can
just point the antennas at each other, using binoculars or a
compass to set the general direction. For accurate alignment,
you must connect a DC voltmeter to the RSSI connector on
the wireless bridge and monitor the voltage as the antenna
moves horizontally and vertically.
•Point-to-Multipoint Configurations – In a point-to-multipoint
configuration all Slave bridges must be aligned with the
Master bridge antenna. The alignment process is the same as
in point-to-point links, but only the Slave end of the link
requires the alignment.
The RSSI connector provides an output voltage between 0 and
3.28 VDC that is proportional to the received radio signal
strength. The higher the voltage reading, the stronger the signal.
The radio signal from the remote antenna can be seen to have a