3Com 3CRWEASYA73, WL-575 User Manual

User Guide

3Com Outdoor 11a Building to Building Bridge and
11bg Access Point

3CRWEASYA73 / WL-575

www.3Com.com

Part Number 10015232 Rev. AA

Published August, 2006

3Com Corporation
350 Campus Drive
Marlborough, MA
01752-3064

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1995) or FAR 52.227-14 (June

Contents

1 Introduction

Product Features 1-1
Radio Characteristics 1-2

APPROVED CHANNELS 1-2
Package Checklist 1-3
Hardware Description 1-4

Integrated High-Gain Antenna 1-4

External Antenna Options 1-4

Ethernet Port 1-5

Power Injector Module 1-5

Grounding Point 1-6

Water Tight Test Point 1-6

Wall- and Pole-Mounting Bracket Kit 1-7
System Configuration 1-7
Operating Modes 1-7

Point-to-Point Configuration 1-8

Point-to-Multipoint Configuration 1-8

2 Bridge Link Planning

Data Rates 2-2
Radio Path Planning 2-3

Antenna Height 2-4

Antenna Position and Orientation 2-6

Radio Interference 2-7

Weather Conditions 2-7
Ethernet Cabling 2-8
Grounding 2-8

3 Hardware Installation

Testing Basic Link Operation 3-2
Mount the Unit 3-2

iii

Using the Pole-Mounting Bracket 3-2

Using the Wall-Mounting Bracket 3-4
Connect External Antennas 3-6
Connect Cables to the Unit 3-7
Connect the Power Injector 3-7
Check the LED Indicators 3-9
Align Antennas 3-10

4 Initial Configuration

Networks with a DHCP Server 4-1

Networks without a DHCP Server 4-1

Using the 3Com Installation CD 4-2

Launch the 3COM Wireless Infrastructure Device Manager (Widman)

utility 4-2

Launching the 3com Wireless Interface Device Manager 4-2

First Time Only 4-4
Using the Setup Wizard 4-4

5 System Configuration

Advanced Setup 5-2
System Identification 5-4
TCP / IP Settings 5-5
RADIUS 5-8
Authentication 5-10
Filter Control 5-15

VLAN 5-17
SNMP 5-19

Configuring SNMP and Trap Message Parameters 5-19

Configuring SNMPv3 Users 5-22
Administration 5-23

Changing the Password 5-23

Telnet and SSH Settings 5-24

Upgrading Firmware 5-25
WDS and Spanning Tree Settings 5-28
System Log 5-33

Enabling System Logging 5-33

Configuring SNTP 5-34

iv

RSSI 5-35
Radio Interface 5-37

802.11a Interface 5-38
Configuring Radio Settings 5-38

Configuring Common Radio Settings 5-39

802.11b/g Interface 5-43

Configuring Wi-Fi Multimedia 5-45

Security 5-50

Wired Equivalent Privacy (WEP) 5-53

Wi-Fi Protected Access (WPA) 5-57

6 Command Line Interface

Using the Command Line Interface 6-1

Accessing the CLI 6-1
Console Connection 6-1

Telnet Connection 6-2

Entering Commands 6-3

Keywords and Arguments 6-3
Minimum Abbreviation 6-3
Command Completion 6-3
Getting Help on Commands 6-3
Showing Commands 6-4
Partial Keyword Lookup 6-4
Negating the Effect of Commands 6-5
Using Command History 6-5
Understanding Command Modes 6-5
Exec Commands 6-5
Configuration Commands 6-6
Command Line Processing 6-6

Command Groups 6-7

A Troubleshooting

B Cables and Pinouts

Twisted-Pair Cable Assignments B-1

10/100BASE-TX Pin Assignments B-2

v

Straight-Through Wiring B-3
Crossover Wiring B-4
8-Pin DIN Connector Pinout B-5
8-Pin DIN to RJ-45 Cable Wiring B-6

Glossary

Index

vi

TERMINOLOGY

Access Point—An internet working device that seamlessly connects

wired and wireless networks.

Ad Hoc—An ad hoc wireless LAN is a group of computers, each with
wireless adapters, connected as an independent wireless LAN.

Backbone—The core infrastructure of a network. The portion of the
network that transports information from one central location to another
central location where it is unloaded onto a local system.

Base Station—In mobile telecommunications, a base station is the
central radio transmitter/receiver that maintains communications with the
mobile radiotelephone sets within its range. In cellular and personal
communications applications, each cell or micro-cell has its own base
station; each base station in turn is interconnected with other cells’ bases.

BSS—Basic Service Set. It is an access point and all the LAN PCs that are
associated with it.

CSMA/CA—Carrier Sense Multiple Access with Collision Avoidance.

EAP—Extensible Authentication Protocol, which provides a generalized

framework for several different authentication methods.

ESS—Extended Service Set. More than one BSS is configured to become
an ESS. LAN mobile users can roam between different BSSs in an ESS
(ESS-ID, SSID).

Ethernet—A popular local area data communications network, which
accepts transmission from computers and terminals.

Infrastructure—An integrated wireless and wired LAN is called an
infrastructure

RADIUS—Remote Access Dial-In User Server is an authentication method
used in conjunction with EAP for 802.1x authentication and session
based keys.

Roaming—A wireless LAN mobile user moves around an ESS and
maintains a continuous connection to the infrastructure network.

configuration.

vii

RTS Threshold—Transmitters contending for the medium may not be
aware of each other (they are “hidden nodes”). The RTS/CTS mechanism
can solve this problem. If the packet size is smaller than the preset RTS
Threshold size, the RTS/CTS mechanism will not be enabled.

VAP—Virtual Access Point. An access point radio capable of operating as
four separate access points.

VLAN—Virtual Local Area Network. A LAN consisting of groups of hosts
that are on physically different segments but that communicate as
though they were on the same segment.

WEP—Wired Equivalent Privacy is based on the use of security keys and
the popular RC4 encryption algorithm. Wireless devices without a valid
WEP key will be excluded from network traffic.

WDS—Wireless Distribution System.

WPA—Wi-Fi Protected Access.

viii

1 INTRODUCTION

The 3Com Outdoor 11a Building to Building Bridge and 11bg Access Point system
provides point-to-point or point-to-multipoint bridge links between remote
Ethernet LANs, and wireless access point services for clients in the local LAN area.

It includes an integrated high-gain antenna for the 802.11a radio and can
operate as a “Slave” or “Master” bridge in point-to-multipoint configurations, or
provide a high-speed point-to-point wireless link between two sites that can be
up to 15.4 km (9.6 miles) apart. As a “Master” bridge in point-to-multipoint
configurations it can support connections to as many as six “Slave” units. The

802.11b/g radio requires an external antenna option.

The unit is housed in a weatherproof enclosure for mounting outdoors and
includes its own bracket for attaching to a wall, pole, radio mast, or tower
structure. The unit is powered through its Ethernet cable connection from a
power injector module that is installed indoors.

The wireless bridge system offers a fast, reliable, and cost-effective solution for
connectivity between remote Ethernet wired LANs or to provide Internet access to
an isolated site. The system is also easy to install and operate, ideal for situations
where a wired link may be difficult or expensive to deploy. The wireless bridge
connection provides data rates of up to 108 Mbps.

In addition, both wireless bridge models offer full network management
capabilities through an easy-to-use web interface, a command-line interface, and
support for Simple Network Management Protocol (SNMP) tools.

PRODUCT FEATURES

 Supports a 5 GHz point-to-point wireless link up 15.4 km (at 6 Mbps data

rate) using the integrated high-gain 17 dBi antenna

 Supports 2.4 GHz or 5 GHz point-to-multipoint links using various external

antenna options

1-1

 Provides access point services for the 5 GHz and 2.4 GHz radios using various

external antenna options

 Maximum data rate up to 108 Mbps on the 802.11a (5 GHz) radio
 Outdoor weatherproof design
 IEEE 802.11a and 802.11b/g compliant
 Local network connection via 10/100 Mbps Ethernet port
 Powered through its Ethernet cable connection to the power injector module
 Brackets for wall- or pole-mount options
 Security through 64/128/152-bit Wired Equivalent Protection (WEP) or 128-bit

Advanced Encryption Standard (AES) encryption

 Scans all available channels and selects the best channel and data rate based

on the signal-to-noise ratio

 Manageable through an easy-to-use web-browser interface, command line, or

SNMP network management tools

RADIO CHARACTERISTICS

The IEEE 802.11a and 802.11g standards use a radio modulation technique
known as Orthogonal Frequency Division Multiplexing (OFDM), and a shared
collision domain (CSMA/CA). The 802.11a standard operates in the 5 GHz
Unlicensed National Information Infrastructure (UNII) band, and the 802.11g
standard in the 2.4 GHz band.

IEEE 802.11g includes backward compatibility with the IEEE 802.11b standard.
IEEE 802.11b also operates at 2.4 GHz, but uses Direct Sequence Spread
Spectrum (DSSS) and Complementary Code Keying (CCK) modulation technology
to achieve a communication rate of up to 11 Mbps.

The wireless bridge provides a 54 Mbps half-duplex connection for each active
channel (up to 108 Mbps in turbo mode on the 802.11a interface).

APPROVED CHANNELS

Use of this product is only authorized for the channels approved by each country.
For proper installation, select your country from the country selection list.

To conform to FCC and other country restrictions your product may be limited in
the channels that are available. If other channels are permitted in your country
please visit the 3Com website for the latest software version.

1-2

PACKAGE CHECKLIST

The 3Com Outdoor 11a Building to Building Bridge and 11bg Access Point
package includes:

 One 3Com Outdoor 11a Building to Building Bridge and 11bg Access Point
 Mounting bracket and hardware
 One Weatherproof Category 5 network cable
 One Weatherproof Console to RS232 cable
 PoE power injector/ Ethernet connector and AC power cord
 One grounding screw, not attached
 One Quick Start Guide
 One CD-ROM containing the Setup Wizard software and User’s Manual
 One Warranty Flyer
 Optional: One N-type RF coaxial cable

Inform your dealer if there are any incorrect, missing or damaged parts. If
possible, retain the carton, including the original packing materials. Use them
again to repack the product in case there is a need to return it.

1-3

HARDWARE DESCRIPTION

Bottom

Console Port
Cap Attachment

Water Tight Test Point
(DO NOT REMOVE)

Console Port with
Protective Cap

Top View

N-Type External Antenna
Connector (2.4 GHz)

Ethernet/PoE
Connector

Grounding
Point

Integrated Antenna

N-Type External Antenna
Connector (5 GHz)

INTEGRATED HIGH-GAIN ANTENNA

The WL-575 bridge includes an integrated high-gain (17 dBi) flat-panel antenna
for 5 GHz operation. With this antenna, in a direct line-of-sight link using a
point-to-point deployment, the range can be as long as 15 km (9.3 miles), with a
6 Mbps data rate.

EXTERNAL ANTENNA OPTIONS

The WL-575 bridge also provides various external antenna options for both 5 GHz
and 2.4 GHz operation. In a point-to-multipoint configuration, an external
high-gain omnidirectional, sector, or high-gain panel antenna can be attached to
communicate with bridges spread over a wide area. The bridge requires a

2.4

GHz external antenna for 802.11b/g operation. The following table

summarizes the external antenna options:

1-4

Item Antenna Type Gain (dBi) Horizontal

2.4 GHz 5.0 GHz

3CWE591 3Com 6/8 dBi Dual-Band Omni 6 8 360 5GHz: 20

3CWE596

3CWE598

* Half-power beam width

3Com 18/20 dBi Dual-Band Panel

3Com 8/10 dBi Dual-Band Panel

18 20 18 19

8 10 60 60

HPBW*

(Degrees)

Vertica l
HPBW*

(Degrees)

2.4GHz: 30

External antennas connect to the N-type RF connectors on the wireless bridge
using the optional RF coaxial cables.

Using the external antennas in a point-to-multipoint deployment, the maximum
range for bridge links are:

 802.11b,g: 2.2 km
 802.11a: 3 km

ETHERNET PORT

The wireless bridge has one 10BASE-T/100BASE-TX 8-pin DIN port that connects
to the power injector module using the included Ethernet cable. The Ethernet
port connection provides power to the wireless bridge as well as a data link to the
local network.

The wireless bridge appears as an Ethernet node and performs a bridging
function by moving packets from the wired LAN to the remote end of the wireless
bridge link.

NOTE: The power injector module does not support Power over Ethernet (PoE)
based on the IEEE 802.3af standard. The wireless bridge unit must always be
powered on by being connected to the power injector module.

POWER INJECTOR MODULE

The wireless bridge receives power through its network cable connection using
power-over-Ethernet technology. A power injector module is included in the
wireless bridge package and provides two RJ-45 Ethernet ports, one for
connecting to the wireless bridge (Output), and the other for connecting to a
local LAN switch (Input).

The Input port uses an MDI (i.e., internal straight-through) pin configuration. You
can therefore use straight-through twisted-pair cable to connect this port to most

1-5

network interconnection devices such as a switch or router that provide MDI-X
ports. However, when connecting the access point to a workstation or other
device that does not have MDI-X ports, you must use crossover twisted-pair cable.

LED Indicator

Input Output

Ethernet from Local
Network

Ethernet and Power
to Wireless Bridge

AC Power Socket
(Hidden)

The wireless bridge does not have a power switch. It is powered on when its
Ethernet port is connected to the power injector module, and the power injector
module is connected to an AC power source. The power injector includes one
LED indicator that turns on when AC power is applied.

The power injector module automatically adjusts to any AC voltage between
100-240 volts at 50 or 60 Hz. No voltage range settings are required.

WARNING: The power injector module is designed for indoor use only. Never mount
the power injector outside with the wireless bridge unit.

!

GROUNDING POINT

Even though the wireless bridge includes its own built-in lightning protection, it is
important that the unit is properly connected to ground. A grounding screw is
provided for attaching a ground wire to the unit.

WATER TIGHT TEST POINT

CAUTION: Do not remove or loosen this screw. Doing so could lead to damage
of the unit.

1-6

WALL- AND POLE-MOUNTING BRACKET KIT

The wireless bridge includes a bracket kit that can be used to mount the bridge to
a wall, pole, radio mast, or part of a tower structure.

SYSTEM CONFIGURATION

At each location where a unit is installed, it must be connected to the local
network using the power injector module. The following figure illustrates the
system component connections.

External Antenna

LAN Switch

OPERATING MODES

The 3Com Outdoor 11a Building to Building Bridge and 11bg Access Point system
provides access point or bridging services through either the 5 GHz or 2.4 GHz
radio interfaces.

The unit supports both point-to-point and point-to-multipoint bridge modes.

Wireless bridge units can be used as regular 802.11a/b/g access points connected
to a local wired LAN, providing connectivity and roaming services for wireless
clients in an outdoor area. Units can also be used purely as bridges connecting
remote LANs. Alternatively, you can employ both access point and bridging
functions together, offering a flexible and convenient wireless solution for many
applications.

Ethernet Cable

AC Power

Indoor Outdoor

Power
Injector

RF Coaxial Cable

Wireless Bridge Unit

Ethernet

Cable

Lightning

Arrestor

Ground Wire

1-7

The wireless bridge modes connect two or more wired networks, for example
networks in different buildings with no wired connections. You will need a 3Com
Outdoor 11a Building to Building Bridge and 11bg Access Point unit on both
sides of the connection. The wireless bridge can connect up to six remote
networks.

When using bridge mode on a radio band, only wireless bridge units can
associate to each other. Wireless clients can only associate with the unit using a
radio band set to access point mode.

POINT-TO-POINT CONFIGURATION

Two bridges can form a wireless point-to-point link using their 5 GHz (802.11a)
integrated antennas. A point-to-point configuration can provide a limited data
rate (6 Mbps) link over a long range (up to 15.4 km), or a high data rate (108
Mbps) over a short range (1.3 km).

POINT-TO-MULTIPOINT CONFIGURATION

A wireless bridge set to “Master” mode can use an omnidirectional antenna to
connect to as many as six bridges in a point-to-multipoint configuration. There
can only be one “Master” unit in the wireless bridge network, all other bridges
must be set as “Slave” units.

The following figure shows a point-to-multipoint “star” configuration with one
bridge set to “Master” and using an omnidirectional antenna.

1-8

The following figure shows a point-to-multipoint “in-line” configuration with one
bridge set to “Master” and using a directional panel antenna.

19° Beam

Angle

1-9

1-10

2 BRIDGE LINK PLANNING

The 3Com Outdoor 11a Building to Building Bridge and 11bg Access Point
supports fixed point-to-point or point-to-multipoint wireless links. A single link
between two points can be used to connect a remote site to larger core network.
Multiple bridge links can provide a way to connect widespread Ethernet LANs.

For each link in a wireless bridge network to be reliable and provide optimum
performance, some careful site planning is required. This chapter provides
guidance and information for planning your wireless bridge links.

NOTE: The planning and installation of the wireless bridge requires professional
personnel that are trained in the installation of radio transmitting equipment.
The user is responsible for compliance with local regulations concerning items
such as antenna power, use of lightning arrestors, grounding, and radio mast or
tower construction. Therefore, it is recommended to consult a professional
contractor knowledgeable in local radio regulations prior to equipment
installation.

2-1

DATA RATES

Using the 5.0 GHz integrated antenna, two WL-575 bridges can operate over a
range of up to 15.4 km (9.6 miles) or provide a high-speed connection of
54

Mbps (108 Mbps in turbo mode). However, the maximum data rate for a link
decreases as the operating range increases. A 15.4 km link can only operate up to
6 Mbps, whereas a 108 Mbps connection is limited to a range of 1.3 km.

When you are planning each wireless bridge link, take into account the maximum
distance and data rates for the various antenna options. A summary for 5.0 GHz
(802.11a) antennas is provided in the following table.

.

Distances Achieved Using 17 dBi Integrated Antennas

Data Rate Distance

6 Mbps 15.4 km

9 Mbps 14.7 km

12 Mbps 14 km

18 Mbps 12.8 km

24 Mbps 11.1 km

36 Mbps 6.5 km

48 Mbps 2.9 km

54 Mbps 1.8 km

12 Mbps Turbo 13.4 km

18 Mbps Turbo 12.8 km

24 Mbps Turbo 12.2 km

36 Mbps Turbo 11.1 km

48 Mbps Turbo 8.2 km

72 Mbps Turbo 4.6 km

96 Mbps Turbo 2.1 km

108 Mbps Turbo 1.3 km

Distances provided in this table are an estimate for a typical

deployment and may be reduced by local regulatory limits.

For accurate distances, you need to calculate the power link

budget for your specific environment.

2-2

RADIO PATH PLANNING

Although the wireless bridge uses IEEE 802.11a radio technology, which is
capable of reducing the effect of multipath signals due to obstructions, the
wireless bridge link requires a “radio line-of-sight” between the two antennas for
optimum performance.

The concept of radio line-of-sight involves the area along a radio link path
through which the bulk of the radio signal power travels. This area is known as
the first Fresnel Zone of the radio link. For a radio link not to be affected by
obstacles along its path, no object, including the ground, must intrude within
60% of the first Fresnel Zone.

The following figure illustrates the concept of a good radio line-of-sight.

Visual Line of Sight

If there are obstacles in the radio path, there may still be a radio link but the
quality and strength of the signal will be affected. Calculating the maximum
clearance from objects on a path is important as it directly affects the decision on
antenna placement and height. It is especially critical for long-distance links,
where the radio signal could easily be lost.

When planning the radio path for a wireless bridge link, consider these factors:

• Avoid any partial line-of-sight between the antennas.

• Be cautious of trees or other foliage that may be near the path, or may grow
and obstruct the path.

Radio Line of Sight

2-3

• Be sure there is enough clearance from buildings and that no building
construction may eventually block the path.

• Check the topology of the land between the antennas using topographical
maps, aerial photos, or even satellite image data (software packages are
available that may include this information for your area)

• Avoid a path that may incur temporary blockage due to the movement of
cars, trains, or aircraft.

ANTENNA HEIGHT

A reliable wireless link is usually best achieved by mounting the antennas at each
end high enough for a clear radio line of sight between them. The minimum
height required depends on the distance of the link, obstacles that may be in the
path, topology of the terrain, and the curvature of the earth (for links over 3
miles).

For long-distance links, a mast or pole may need to be constructed to attain the
minimum required height. Use the following table to estimate the required
minimum clearance above the ground or path obstruction (for 5.0 GHz bridge
links).

.

Max Clearance
Total Link
Distance

0.25 mile (402 m) 4.5 ft (1.4 m) 0 4.5 ft (1.4 m)

0.5 mile (805 m) 6.4 ft (1.95 m) 0 6.4 ft (1.95 m)

1 mile (1.6 km) 9 ft (2.7 m) 0 9 ft (2.7 m)

2 miles (3.2 km) 12.7 ft (3.9 m) 0 12.7 ft (3.9 m)

3 miles (4.8 km) 15.6 ft (4.8 m) 1.8 ft (0.5 m) 17.4 ft (5.3 m)

4 miles (6.4 km) 18 ft (5.5 m) 3.2 ft (1.0 m) 21.2 ft (6.5 m)

5 miles (8 km) 20 ft (6.1 m) 5 ft (1.5 m) 25 ft (7.6 m)

7 miles (11.3 km) 24 ft (7.3 m) 9.8 ft (3.0 m) 33.8 ft (10.3 m)

9 miles (14.5 km) 27 ft (8.2 m) 16 ft (4.9 m) 43 ft (13.1 m)

12 miles (19.3 km) 31 ft (9.5 m) 29 ft (8.8 m) 60 ft (18.3 m)

15 miles (24.1 km) 35 ft (10.7 m) 45 ft (13.7 m) 80 ft (24.4 m)

17 miles (27.4 km) 37 ft (11.3 m) 58 ft (17.7 m) 95 ft (29 m)

for 60% of First

Fresnel Zone at

5.8 GHz

2-4

Approximate
Clearance for
Earth Curvature

Total Clearance
Required at
Mid-point of
Link

Note that to avoid any obstruction along the path, the height of the object must
be added to the minimum clearance required for a clear radio line-of-sight.
Consider the following simple example, illustrated in the figure below.

Radio Line of Sight

5.4 m

B

1.4 m

9m

12 m

2.4 m

20 m

Visual Line of Sight

3 miles (4.8 km)

A

17 m

A wireless bridge link is deployed to connect building A to a building B, which is
located three miles (4.8 km) away. Mid-way between the two buildings is a small
tree-covered hill. From the above table it can be seen that for a three-mile link,
the object clearance required at the mid-point is 5.3 m (17.4 ft). The tree-tops on
the hill are at an elevation of 17 m (56 ft), so the antennas at each end of the link
need to be at least 22.3 m (73 ft) high. Building A is six stories high, or 20 m (66
ft), so a 2.3 m (7.5

ft) mast or pole must be constructed on its roof to achieve the
required antenna height. Building B is only three stories high, or 9 m (30 ft), but is
located at an elevation that is 12 m (39 ft) higher than building A. To mount an
antenna at the required height on building B, a mast or pole of only 1.3 m (4.3 ft)
is needed.

WARNING: Never construct a radio mast, pole, or tower near overhead power
lines.

!

NOTE: Local regulations may limit or prevent construction of a high radio mast
or tower. If your wireless bridge link requires a high radio mast or tower, consult
a professional contractor for advice.

2-5

ANTENNA POSITION AND ORIENTATION

Once the required antenna height has been determined, other factors affecting
the precise position of the wireless bridge must be considered:

• Be sure there are no other radio antennas within 2 m (6 ft) of the wireless
bridge

• Place the wireless bridge away from power and telephone lines

• Avoid placing the wireless bridge too close to any metallic reflective surfaces,
such as roof-installed air-conditioning equipment, tinted windows, wire
fences, or water pipes

• The wireless bridge antennas at both ends of the link must be positioned
with the same polarization direction, either horizontal or vertical

Antenna Polarization — The wireless bridge’s integrated antenna sends a radio
signal that is polarized in a particular direction. The antenna’s receive sensitivity is
also higher for radio signals that have the same polarization. To maximize the
performance of the wireless link, both antennas must be set to the same
polarization direction. Ideally the antennas should be pointing upwards mounted
on the top part of a pole.

2-6

RADIO INTERFERENCE

The avoidance of radio interference is an important part of wireless link planning.
Interference is caused by other radio transmissions using the same or an adjacent
channel frequency. You should first scan your proposed site using a spectrum
analyzer to determine if there are any strong radio signals using the 802.11a
channel frequencies. Always use a channel frequency that is furthest away from
another signal.

If radio interference is still a problem with your wireless bridge link, changing the
antenna polarization direction may improve the situation.

NOTE: For US operation of 5 GHz WDS links, avoid possible radio link disruption
from radar by selecting the following recommended RF channels -- Normal
mode: 49, 153, 157, 161, 165, Turbo mode: 42, 152, 160.

WEATHER CONDITIONS

When planning wireless bridge links, you must take into account any extreme
weather conditions that are known to affect your location. Consider these
factors:

• Te mp e ra tu re — The wireless bridge is tested for normal operation in
temperatures from -40°C to 60°C. Operating in temperatures outside of this
range may cause the unit to fail.

• Wind Velocity — The wireless bridge can operate in winds up to 100 MPH
and survive higher wind speeds up to 150 MPH. You must consider the
known maximum wind velocity and direction at the site and be sure that any
supporting structure, such as a pole, mast, or tower, is built to withstand this
force.

• Lightning — The wireless bridge includes its own built-in lightning
protection. However, you should make sure that the unit, any supporting
structure, and cables are all properly grounded. Additional protection using
lightning rods, lightning arrestors, or surge suppressors may also be
employed.

• Rain — The wireless bridge is weatherproofed against rain. Also, prolonged
heavy rain has no significant effect on the radio signal. However, it is
recommended to apply weatherproof sealing tape around the Ethernet port
and antenna connectors for extra protection. If moisture enters a connector,
it may cause a degradation in performance or even a complete failure of the
link.

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• Snow and Ice — Falling snow, like rain, has no significant effect on the
radio signal. However, a build up of snow or ice on antennas may cause the
link to fail. In this case, the snow or ice has to be cleared from the antennas
to restore operation of the link.

ETHERNET CABLING

When a suitable antenna location has been determined, you must plan a cable
route form the wireless bridge outdoors to the power injector module indoors.
Consider these points:

• The Ethernet cable length should never be longer than 100 m (328 ft)

• Determine a building entry point for the cable

• Determine if conduits, bracing, or other structures are required for safety or
protection of the cable

• For lightning protection at the power injector end of the cable, use a
lightning arrestor immediately before the Ethernet cable enters the building

GROUNDING

It is important that the wireless bridge, cables, and any supporting structures are
properly grounded. The wireless bridge unit includes a grounding screw for
attaching a ground wire. Be sure that grounding is available and that it meets
local and national electrical codes.

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3 HARDWARE INSTALLATION

Before mounting antennas to set up your wireless bridge links, be sure you have
selected appropriate locations for each antenna. Follow the guidance and
information in Chapter 2, “Wireless Link Planning.”

Also, before mounting units in their intended locations, you should first perform
initial configuration and test the basic operation of the wireless bridge links in a
controlled environment over a very short range. (See the section “Testing Basic
Link Operation” in this chapter.)

The wireless bridge includes its own bracket kit for mounting the unit to a 1.5 to
2

inch diameter steel pole or tube. The pole-mounting bracket allows the unit to
be mounted to part of a radio mast or tower structure. The unit also has a
wall-mounting bracket kit that enables it to be fixed to a building wall or roof
when using external antennas.

Hardware installation of the wireless bridge involves these steps:

1 Mount the unit on a wall, pole, mast, or tower using the mounting bracket.

2 Mount external antennas on the same supporting structure as the bridge and

connect them to the bridge unit.

3 Connect the Ethernet cable and a grounding wire to the unit.

4 Connect the power injector to the Ethernet cable, a local LAN switch, and an

AC power source.

5 Align antennas at both ends of the link.

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TESTING BASIC LINK OPERATION

Set up the units over a very short range (15 to 25 feet), either outdoors or
indoors. Connect the units as indicated in this chapter and be sure to perform all
the basic configuration tasks outlined in Chapter 4, “Initial Configuration.” When
you are satisfied that the links are operating correctly, proceed to mount the units
in their intended locations.

MOUNT THE UNIT

The bridge can be mounted on the following types of surfaces:

 Pole
 Wall

CAUTION: The bridge is intended for outdoor use only. Do not install the bridge
indoors.

!

USING THE POLE-MOUNTING BRACKET

Perform the following steps to mount the unit to a 1.5 to 2 inch diameter steel
pole or tube using the mounting bracket:

1 Place the V-shaped part of the bracket around the pole and tighten the

securing nuts just enough to hold the bracket to the pole. (The bracket may
need to be rotated around the pole during the antenna alignment process.)

Attach V-shaped
parts to pole with
provided nuts and
bolts

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2 Fit the edges of the V-shaped part into the slots in the rectangular plate, and

tighten the nuts.

Fit the edges of
the V-shaped
part into the slots

3 Attach the adjustable rectangular plate to the bridge with supplied screws.

Attach the
adjustable
rectangular plate
to the bridge

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4 Attach the bridge with bracket to the plate already fixed to the pole.

Attach the bridge
to the plate on
the pole

5 Use the included nuts to secure the wireless bridge to the pole bracket. Note

that the wireless bridge tilt angle may need to be adjusted during the
antenna alignment process.

Be sure to take account of the antenna polarization direction; all antennas in
a link must be mounted with the same polarization.

USING THE WALL-MOUNTING BRACKET

Perform the following steps to mount the unit to a wall using the wall-mounting
bracket:

CAUTION: The wall-mounting bracket does not allow the wireless bridge’s
intrgrated antenna to be aligned. It is intended for use with the unit using an

!

external antenna.

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