Redline Communications AN-50, Руководство пользователя

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AN-50 System User Manual
Redline Communications …..solving the first mile challenge .
9.4. Deployment Scenarios
This section provides a general overview of typical AN-50 Point to Multi-Point (PMP)
deployment scenarios.
The AN-50 base station PMP system supports both 60 and 90 degree cell sectorization,
as illustrated below.
Figure 28: Cell Sectorization
The advantage of the narrower 60 degree beam antenna is that it achieves higher
subscriber density per cell through frequency reuse, higher gain (at greater distances)
and provides greater flexibility in dealing with external interference, again through proper
reuse of the channels. In terms of capacity, the 60 degree pattern can provide a
threefold increase in bandwidth over an omni pattern, while the 90 degree sectorization
scheme can double the bandwidth. This is achieved by reusing the bandwidth – for
example, assume there are two channels, A and B. The 60 degree scheme can support
a sector-to-sector scheme of AB-AB-AB while the 90 degree can support AB-AB. In
terms of interference, a narrower sector provides finer granularity in isolating and re-
allocating channels to avoid the problem, whereas a larger sector has less flexibility.
The key advantage of the 90 degree sector antenna is that fewer systems are required
at the base station to provide full omni coverage. This is an important consideration
when trying to limit the initial capital expenditure necessary to create and grow the
network.
Another means of gracefully growing the network, using narrower sectors, is to begin
with a single sector, and then, as the customer base grows in other directions, to add
sectors until full coverage is achieved. This is shown below, starting with one sector, to
three and then to the full 6 sectors in final deployment.
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