Wilan LIBRA 5800 AP, User Manual

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Description
18 Libra 5800 Series User Guide
the system. Once they are ready to transmit or receive they will move up the polling list and will be
polled more often.
Time Division Multiplexing/Time Division Multiple Access (TDM/TDMA)
Antenna characteristics and placement are critical. Because of W-OFDM’s excellent Non-Line of
Sight performance and its resistance to frequency selective multipath fading CPE directional
antennas do not have to be pointed directly at the AP antenna. Having a clear line of sight is always
preferable, but is not necessary with the BWS series. There are cases in which the optimal
performance is acheived when the CPE antenna does not point directly to the AP (e.g. when using
reflection off a nearby structure to avoid an absorbing obstruction).
About Point-to-Point (P-P) Systems
For P-P systems Libra 5800 comes in two versions, the Rapid Deployment (RD) and the Extended
Range (ER) units. P-P links are used when only two locations are connected, for example for
backhaul purposes between P-MP Base Stations and the Network Operating Center for connection
to the Internet backbone, or in situations where throughput requirements between two locations are
such that the bandwidth can’t be shared.
Rapid Deployment (RD) Equipment
The RD equipment is intended for very rapid installation of a P-P link and can be used for links of up
to 16 kms (up to 12 kms at full 32 Mbps bandwidth).
RD Equipment has two parts: 1) RD and 2) Ethernet Power Inserter with CAT-5 cable (bought
separately) and weatherproofing kit (included).
• LIBRA 5800 RD – The RD is the main piece of equipment that is normally installed outdoors
(indoor installation is permitted when the range and link budget allows it) The RD contains all
of the necessary radio equipment to provide a high-speed wireless link. The RD also has an
integral 23 dBi antenna such that no RF cables are required for a typical installation.
• Ethernet Power Inserter – This piece of equipment is a small box that connects between the
RD and the Ethernet network. This box also provides power for the RD equipment to run. A
CAT-5 outdoor cable is used to connect the Power inserter to the RD. The weatherproofing kit
is used with standard RJ-45 connector to ensure reliable connection for outdoor systems.
DL
slot1
DL
slot2
UL SF1
......
DL slot-n
DL superframe
DL TDM
UL SF2 UL SFm
UL TDMA
UL superframes