User guide

45 Mbps Backhaul User Guide
Issue 3, December 2004 Page 103 of 113
11.8.5 Mounting
11.8.5.1 Connectorized 45 Mbps Backhaul unit
A connectorized 45 Mbps Backhaul unit is supplied with the same bracket as supplied with a integrated antenna
45 Mbps Backhaul. Details on the use of this bracket can be found in section 1.3.6 “Mounting Brackets”. The
connectorized 45 Mbps Backhaul unit should be mounted in a position that gives it maximum protection from
the elements but still allows easy access for making off the various connections and applying the recommended
weatherproofing.
When using dual polar antennas the 45 Mbps Backhaul unit should be mounted in such a position as to
minimize the cable length keeping losses to a minimum (taking into account the minimum cable lengths
required by the FCC regulations, see section 11.7 ”Antennas for USA / Canada”).
When using separate antennas the 45 Mbps Backhaul unit should be mounted in such a position as to minimize
both cable runs between the 45 Mbps Backhaul unit and the antennas. It is not necessary to mount the 45 Mbps
Backhaul unit at the mid point between the antennas.
11.8.5.2 Antennas
The Antennas should be mounted according to the manufacturers instructions. Actual antenna position will
depend on the available mounting positions and link requirements. It may be necessary to mount the antennas
20m apart or at a certain distance from the ground to get the desired results.
11.8.6 Alignment Process
When aligning antennas deployed with a connectorized 45 Mbps Backhaul it may not be possible to hear the
alignment tone emanating from the ODU. In this case it may be necessary for a second installer to assist in the
operation. Alternately it may be possible to extend the tube on the supplied stethoscope to give a longer reach.
Tip Fine antenna alignment can sometimes be achieved by tightening and loosening the bolts on either side of
the antenna mounting bracket, rather than trying to turn the whole bracket on the mounting pole.
11.8.6.1 Dual Polar Antennas
The process for aligning a dual polar antenna is the same as aligning a 45 Mbps Backhaul-I unit with an
integrated antenna. This procedure is detailed in section 5.7.9 ”Aligning the ODUs”.
11.8.6.2 Separate Antennas
When using separate antennas to achieve special diversity it is recommended that one be mounted with
Horizontal polarization and the other with Vertical polarization.
The following steps should be followed:
Step 1: Mount the Antennas
Step 2: Mount the 45 Mbps Backhaul unit
Step 3: Route and make off the ends of the Antenna cables
Step 4: Connect the antenna cables at the antennas
Step 5: Connect one of the antenna cables at the 45 Mbps Backhaul unit