User's Manual

Table Of Contents

WIRELESS NETWORK DESIGN

Centralized (Star) Topology

2-4 P-Com DataMetro II

Figure 2-3 Star Topology

A directional antenna can be used for the central site if all of the

nodes fall in the main lobe of the antenna pattern. Since the

remote sites need only communicate with the central site,

directional, high gain antennas can be used.

The range of a Star topology network can be increased if the

remote nodes are all located within a confined sector from the

central site. Communication between two remote sites must be

relayed through the central node.

Medium access contention on the Star Base is resolved by the

specific Star Base MAC protocol. The Star Remote sends the data

frame only when it gets permission from the Star Base. Each

frame regularly transmitted by the Star Base contains the PID

(polling ID) of the wireless cluster node. If a polled Star Remote

has a frame to transmit, it explicitly sends the frame to the Star

Base. The Star Base relays this frame to the Star Remotes

indicated by the DID (destination ID) of the original frame. A

polled Star Remote does not reply on the PID if it has no frame to

transmit.

DATAMETRO II

BASE STATION

REMOTE STATIONS

Ethernet