Microwave Data Systems MDS entraNET 900, Системное руководство

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8 MDS entraNET 900 System Guide (Preliminary) MDS 05-4055A01, Rev. A
1.3 NETWORK DESIGN
CONSIDERATIONS
1.3.1 Extending Network Coverage with Repeaters
What is a Repeater System?
A repeater works by re-transmitting data from outlying remote sites to
the Access Point and vice-versa. As with any other store-and-forward
device, it introduces additional end-to-end transmission delay but pro-
vides longer-range connectivity.
In some geographical areas obstacles can make communications diffi-
cult. These obstacles commonly are large buildings, hills or dense
foliage. These obstacles can often be overcome with a repeater station.
The geographic location of a repeater station is especially important. A
site must be chosen that allows good communication from the repeater
to
both the Access Point and outlying remote sites. This location is often
on top of a hill, or other elevated terrain from which both sites can be
“seen” by the repeater station antennas. A detailed discussion on the
effects of terrain is given in
Section 5.1.2, Site Selection (beginning on
Page 105) .
Using a Remote as a Store-and-Forward Repeater
A wireless network can be extended through the use of an alternate
arrangement using the Access Point as a repeater to re-transmit the sig-
nals of all stations in the network. The repeater is a standard transceiver
configured as an Access Point. (See
Figure 1-4 .)
Invisible place holder
Figure 1-4. Typical network with store-and-forward repeater
1.3.2 Protected Network Operation through Multiple
Access Points
Although MDS entraNET 900 units have a very robust design and have
undergone intensive testing before shipment it is possible for isolated
failures to occur. Down time can be further reduced by using some, or
all, of the following configurations.
Remote
Remote
Access Point
LAN/WAN
STORE & FORWARD
REPEATER
LAN
POINT-TO-POINT LINK