Afar AR-24010E, Руководство оператора

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pulsAR radio Operator's Manual
2.1.3 Tree topology
In a tree topology you have three node types: one root node and multiple branch and leaf nodes (use
the node command to configure the node type).
The root node performs a similar function to the hub in a point-to-multipoint topology and can have
up to 32 direct links to remote sites. The radios at the remote sites can be configured as either leaf or
branch nodes. A leaf node is similar to the remote in a point-multipoint topology. But a branch
node, besides having a link to a parent (root or another branch), also operates as an access point for
up to 32 additional remote nodes ( children ). Each of those nodes can again be configured as either a
leaf or a branch . There is no limit to the number of levels in the tree.
A branch node has two independent RF configurations, one for the link with the parent, the other for
the links with its children. Typically you set the link with the parent to use antenna A, and the link
with the children to use antenna B. This allows you to deploy a directional antenna pointing at the
parent node, while using an omni-directional or sectorial antenna for the links with the multiple
children. This is not mandatory, you can configure a branch radio to use a single antenna.
With a large network with many branch nodes you must pay special attention to the channel
assignments. One simple approach is to allocate non-overlapping channels to each “cell” (a cell
consists of a parent with all of its direct children). At the parent set both the transmit and receive
channel to the channel that you assigned to that cell. At the children set them to receive from the
2-3
Figure 2.1: Tree Topology
Root
Branch
Leaf
Root
Branch
Leaf