WaveRider NCL1135 User manual

NCL1135 User Manual
Version 1.0

WaveRider Communications Inc.
Software License Agreement
This is a legal agreement between you (either an individual or an entity) and WaveRider Communications Inc. for the use
of WaveRider computer software, hereinafter the “LICENSED SOFTWARE”.
By using the LICENSED SOFTWARE installed in this product, you acknowledge that you have read this license
agreement, understand it, and agree to be bound by its terms. You further agree that it is the full and complete
agreement between you and WaveRider Communications Inc., superseding all prior written or verbal agreements of any
kind related to the LICENSED SOFTWARE. If you do not understand or do not agree to the terms of this agreement, you
must cease using the LICENSED SOFTWARE immediately.
1 GRANT OF LICENSE—This License Agreement permits you to use one copy of the LICENSED SOFTWARE.
2. COPYRIGHT—The LICENSED SOFTWARE is owned by WaveRider Communications Inc. and is protected by
copyright laws and international treaty provisions; therefore, you must treat the LICENSED SOFTWARE like
any other copyrighted material (e.g., a book or magazine). You may not copy the written materials
accompanying the LICENSED SOFTWARE.
3. OTHER RESTRICTIONS—You may not rent or lease the LICENSED SOFTWARE. You may not reverse
engineer, decompile, or disassemble the LICENSED SOFTWARE.
4. LIMITED WARRANTY—The LICENSED SOFTWARE is provided “as is” without any warranty of any kind,
either expressed or implied, including, but not limited to, the implied warranties of merchantability and fitness
for a particular purpose. The entire risk as to the quality and performance of the LICENSED SOFTWARE is
with you, the licensee. If the LICENSED SOFTWARE is defective, you assume the risk and liability for the
entire cost of all necessary repair, service, or correction.
Some states/jurisdictions do not allow the exclusion of implied warranties, so the above exclusion
may not apply to you. This warranty gives you specific legal rights, and you may have other rights,
which vary from state/jurisdiction to state/jurisdiction.
WaveRider Communications Inc. does not warrant that the functions contained in the LICENSED
SOFTWARE will meet your requirements, or that the operation of the LICENSED SOFTWARE will be
error-free or uninterrupted.
5. NOOTHER WARRANTIES—To the maximum extentpermitted by applicable law, WaveRider Communications
Inc. disclaims all other warranties, either express or implied, including, but not limited to, the implied warranties
of merchantability and fitness for a particular purpose, with regard to the LICENSED SOFTWARE and the
accompanying written materials.
6. NO LIABILITY FOR CONSEQUENTIAL DAMAGES—To the maximum extent permitted by applicable law, in
no event shall WaveRider Communications Inc. or its suppliers be liable for any damages whatsoever
(including, without limitation, damages for loss of business profits, business interruption, loss of business
information, or any other pecuniary loss) arising from the use ofor inability to use the LICENSED SOFTWARE,
even if WaveRider Communications Inc. has been advised of the possibility of such damages, or for any claim
by any other party.
Because some states/jurisdictions do not allow the exclusion or limitation of liability for consequential
or incidental damages, the above limitation may not apply to you.
In no event will WaveRider’s liability exceed the amount paid for the LICENSED SOFTWARE.

The following are trademarks or registered trademarks of
their respective companies or organizations:
Microsoft Internet Explorer/Microsoft Corporation
Netscape/Netscape Communications Corporation
© 2000 by WaveRider Communications Inc. All rights
reserved. This manual may not be reproduced by any means
in whole or in part without the express written permission of
WaveRider Communications Canada Inc.
Version 1.0, July 2000

Warranty
In the following warranty text, “WaveRider®” shall mean WaveRider Communications Inc.
This WaveRider product is warranted against defects in material and workmanship for a period of one (1) year from the
date of purchase. This limited warranty extends only to the original purchaser. During this warranty period WaveRider
will, at its option, either repair or replace products that prove to be defective.
For warranty service or repair, the product must be returned to a service facility designated by WaveRider. Authorization
to return products must be obtained prior to shipment. The WaveRider RMA number must be on the shipping
documentation so that the service facility will accept the product. The buyer shall pay all shipping charges to WaveRider
and WaveRider shall pay shipping charges to return the product to the buyer within Canada or the USA. For all other
countries, the buyer shall pay shipping charges as well as duties and taxes incurred in shipping products to or from
WaveRider.
WaveRider warrants that the firmware designed by it for use with the unit will execute its programming instructions when
properly installed on the unit. WaveRider does not warrant that the operation of the unit or firmware will be uninterrupted
or error-free.
Limitation of Warranty
The foregoing warranty shall not apply to defects resulting from improper or inadequate maintenance by the buyer,
buyer-supplied interfacing, unauthorized modification or misuse, operation outside the environmental specifications for
the product, or improper site preparation or maintenance or exposure to abnormal physical or electrical stress or
accident. No other warranty is expressed or implied. WaveRider specifically disclaims the implied warranties of
merchantability and fitness for any particular purpose.
No Liability for Consequential Damages
To the maximum extent permitted by applicable law, in no event shall WaveRider or its suppliers be liable for any
damages whatsoever (including, without limitation, damages for loss of business profits, business interruption, loss of
business information, or any other pecuniary loss) arising from the use of or inability to use the product, even if
WaveRider has been advised of the possibility of such damages, or for any claim by any other party.
Because some states/jurisdictions do not allow the exclusion or limitation of liability for consequential or incidental
damages, the above limitation may not apply to you.
In no event will WaveRider’s liability exceed the amount paid for the product.
Regulatory Notices
This equipment has been tested and found to comply with the limits for a Class A Intentional Radiator, pursuant to Part
15 of the FCC Regulations, and RSS-210 of the IC Regulations. These limits are intended to provide protection against
harmful interference when the equipment is operated in a commercial/business/industrial environment.
This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance
with the instruction manual, may cause harmful interference to radio communications. However, there is no guarantee
that interference will not occur in a particular installation.
Notice to User
Any changes or modifications to equipment that are not expressly approved by the manufacturer may void the user’s
authority to operate the equipment. The NCL1135 contains no user-serviceable parts. Unauthorized opening of the unit
voids this warranty.

APCD–NC003–1.0 v
Contents
Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .ix
1 NCL1135 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.1 Introduction to the NCL1135 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 Spread-Spectrum Radio Technology. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2 Network Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.1 Network Topology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.1.1 Point-to-Point . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.1.2 Repeater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.1.3 Point-to-Multipoint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.2 Bridging and Routing Network Configurations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.2.1 Point-to-Multipoint Bridging Network . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.2.2 Point-to-Multipoint Routing Network . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.3 Planning an NCL1135 Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3 Configuring the NCL1135 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
3.1 Connecting and Initializing the NCL1135. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
3.1.1 Changing the NCL1135 Password . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
3.1.2 Setting the NCL1135 System Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
3.1.3 Resetting an NCL1135 to Factory Settings . . . . . . . . . . . . . . . . . . . . . . . 15
3.2 Configuring the NCL1135 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
3.2.1 Setting the Radio Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
3.2.2 Setting the IP Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Setting the DHCP Relay Configuration . . . . . . . . . . . . . . . . . . . . . . . . . 19
Setting the SNMP Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Setting the DNS Resolver Configuration . . . . . . . . . . . . . . . . . . . . . . . 21
3.3 Examples of Bridging and Routing Configurations . . . . . . . . . . . . . . . . . . . . . . . . 22
3.3.1 Point-to-Multipoint Bridging Network . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
3.3.2 Point-to-Multipoint Routing Network . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
3.4 Updating an NCL1135 Using Remote Connections. . . . . . . . . . . . . . . . . . . . . . . . 30
3.4.1 Establishing an FTP Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
3.4.2 Establishing a Telnet Session . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
3.4.3 Establishing a Web Browser Connection . . . . . . . . . . . . . . . . . . . . . . . . . 31
4 Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
4.1 Performing a Ping Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
5 Deploying the NCL1135 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
5.1 Optimizing Signal Strength . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
5.1.1 Running the Continuous Transmit (Tx) Test . . . . . . . . . . . . . . . . . . . . . . 35
5.1.2 Running the Continuous Receive (Rx) Test . . . . . . . . . . . . . . . . . . . . . . . 37
5.1.3 Performing the Transmit/Receive Loopback Test . . . . . . . . . . . . . . . . . . 39

vi APCD–NC003–1.0
6 Operational Statistics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
6.1 Displaying the Radio Packet Error Rate (PER) . . . . . . . . . . . . . . . . . . . . . . . . . . 41
6.2 Displaying the Operational Statistics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
6.2.1 Interface Statistics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
6.2.2 IP Statistics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
6.2.3 Radio Statistics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
7 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
7.1 Verifying NCL1135 Routing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
7.1.1 Verify the NCL1135 Routing Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Appendix A NCL1135 Command-Line Syntax . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Appendix B Abbreviations and Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Appendix C Operating Channel Frequencies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
Appendix D NCL1135 Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Appendix E Configuration Data Record . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

APCD–NC003–1.0 vii
Figures
Figure 1 NCL1135 Network Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Figure 2 Point-to-Point Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Figure 3 Repeater Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Figure 4 Point-to-Multipoint Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Figure 5 Point-to-Multipoint Bridging Network Example . . . . . . . . . . . . . . . . . . . . . . . 8
Figure 6 Point-to-Multipoint Routing Network Example . . . . . . . . . . . . . . . . . . . . . . . . 9
Figure 7 NCL1135 Configuration Planning Flowchart . . . . . . . . . . . . . . . . . . . . . . . . 10
Figure 8 NCL1135 Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Figure 9 Console Port Pin-out Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Figure 10 Example Point-to-Multipoint Bridging Network . . . . . . . . . . . . . . . . . . . . . . 22
Figure 11 Example Point-to-Multipoint Routing Network . . . . . . . . . . . . . . . . . . . . . . . 25

viii APCD–NC003–1.0
Tables
Table 1 Radio Packet Error Rate Assessment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Table 2 Interface Statistics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Table 3 IP Statistics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Table 4 Radio Statistics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Table 5 Common Problems and Solutions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Table 6 NCL1135 Command-Line Syntax Conventions . . . . . . . . . . . . . . . . . . . . . . 55
Table 7 Command-Line Shortcuts and Getting Help . . . . . . . . . . . . . . . . . . . . . . . . 56
Table 8 NCL1135 Command-line Syntax Descriptions . . . . . . . . . . . . . . . . . . . . . . 56
Table 9 Acronyms and Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Table 10 NCL1135 Network Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
Table 11 Radio Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Table 12 Ethernet Interface Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Table 13 Power Supply Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Table 14 Environmental Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

APCD–NC003–1.0 ix
Preface
About this Manual
WaveRider recommends that you read the following sections before you install and operate
the NCL1135:
•
Software License Agreement on page ii
•
Warranty on page iv
•
Regulatory Notices on page x
•
Warnings and Advisories on page xii
This NCL1135 User Manual provides you with information necessary for planning, installing,
and operating an NCL1135-based system. The information has been organized in the
following sections:
Chapter 1 Provides an overview of the NCL1135 and the spread-spectrum radio
technology.
Chapter 2 Describes some typical configurations and provides a flowchart to assist you
in planning your network.
Chapter 3 Provides the procedures to set up and configure the NCL1135.
Chapter 4 Describes a ping test that confirms the NCL1135 is configured and ready to
be deployed.
Chapter 5 Provides three tests useful when deploying an NCL1135.
Chapter 6 Describes how to obtain the NCL1135 operational statistics.
Chapter 7 Lists typical NCL1135 problems, possible causes, and solutions.
Appendix A Lists all commands available for the NCL1135.
Appendix B Provides a list of acronyms and abbreviations and a list of the NCL1135
wireless network terminology used in this manual.
Appendix C Lists the channel frequency set for each WaveRider regulatory domain.
Appendix D Provides the NCL1135 technical specifications.
Appendix E Contains a form that you can use to record the configuration information.
NOTE: The information contained in this manual is subject to change
without notice.

xAPCD–NC003–1.0
Regulatory Notices
Industry Canada
The NCL1135 complies with IC RSS–210.
Operators must be familiar with IC RSS–210 and RSS–102.
The IC certification number for the NCL1135 is 32251021662A.
Federal Communications Commission
The NCL1135 complies with FCC Part 15 Regulations.
The FCC ID for the NCL1135 is OOX-NCL1100.
The transmitter of this device complies with Part 15.247 of the FCC Rules.
WARNING!
Operators must be familiar with the requirements of the FCC
Part 15 Regulations prior to operating any link using this
equipment. For installations outside the United States, contact
local authorities for applicable regulations.
Interference Environment
Manufacturers and operators of spread-spectrum devices are reminded that the operation of
these devices is subject to the conditions that:
• Any received interference, including interference from industrial, scientific, and
medical (ISM) operations, must be accepted; and
• These devices are not permitted to cause harmful interference to other radio services.
If the operation of these systems does cause harmful interference, the operator of the spread-
spectrum system must correct the interference problem, even if such correction requires the
Part 15 transmitter to cease operation. The FCC does not exempt spread-spectrum devices
from this latter requirement regardless of the application. The FCC strongly recommends that
utilities, cellular stations, public safety services, government agencies, and others that provide
critical communication services exercise due caution to determine if there are any nearby
radio services that can be affected by their communications.

APCD–NC003–1.0 xi
Operational Requirements
In accordance with the FCC Part 15 regulations:
1. The maximum peak power output of the intentional radiator shall not exceed one (1)
watt for all spread-spectrum systems operating in the 2.4000-2.4835 GHz band.
2. Systems operating in the 2.4000-2.4835 GHz band that are used exclusively for fixed,
point-to-point operations may employ transmitting antennas with directional gain
greater than 6 dBi, provided the maximum peak output power of the intentional
radiator is reduced by 1 dB for every 3 dB that the directional gain of the antenna
exceeds 6 dBi.
3. Stations operating in the 2.400-2.4835 GHz band that are used for fixed, point-to-
multipoint operations may use transmitting antennas of directional gain greater that 6
dBi, provided the peak output power from the intentional radiator is reduced by the
amount in dB that the directional gain of the antenna exceeds 6 dBi.
4. Fixed, point-to-point operation, as used in Point 2, excludes the use of point-to-
multipoint systems, omni-directional applications, and multiple co-located intentional
radiators transmitting the same information. The operator of the spread-spectrum
intentional radiator or, if the equipment is professionally installed, the installer is
responsible for ensuring that the system is used exclusively for fixed, point-to-point
operations.
5. The operator of a spread-spectrum system is responsible for ensuring that the system
is operated in the manner outlined in
Interference Environment on page x and
Operational Requirements on page xi.

xii APCD–NC003–1.0
Warnings and Advisories
General Advisory
Operator and maintenance personnel must be familiar with the related safety requirements
before they attempt to install or operate the NCL1135 equipment.
It is the responsibility of the operator to ensure that the public is not exposed to excessive
Radio Frequency (RF) levels. The applicable regulations can be obtained from local
authorities.
WARNING!
This system must be professionally installed. Antennas and
associated transmission cable must be installed by qualified
personnel. WaveRider assumes no liability for failure to adhere
to this recommendation or to recognized general safety
precautions.
WARNING!
To comply with FCC RF exposure limits, the antenna for this
transmitter must be fix-mounted on outdoor permanent
structures to provide a separation distance of 32 cm (12 inches)
or more from all persons to satisfy RF exposure requirements.
The distance is measured from the front of the antenna and the
human body. It is recommended that the antenna be installed in
a location with minimal pathway disruption by nearby personnel.
WARNING!
Do not operate the NCL1135 without connecting a 50-ohm
termination to the antenna port. This termination can be a
50-ohm antenna or a 50-ohm resistive load capable of absorbing
the full RF output power of the transceiver. Failure to terminate
the antenna port properly may cause permanent damage to the
NCL1135.

APCD–NC003–1.0 xiii
Customer Support
If you have any problems with the hardware or software, please contact WaveRider
Communications Inc. Please provide your NCL1135 Model number and software version
when you request support.
WaveRider offers a complete training program. Please contact your sales representative for
training information.
Telephone: [phone]
Fax: [phone]
Email: [e-mail]
URL: www.waverider.com

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APCD–NC003–1.0 1
1 NCL1135 Overview
1.1 Introduction to the NCL1135
The NCL1135 is an intelligent, wireless Internet Protocol (IP) router/bridge that provides high-
capacity wireless 2.4 GHz connections between local- and wide-area networks. The NCL1135
uses direct-sequence spread spectrum (DSSS) techniques to provide secure communications
and is completely network configurable.
Figure 1 shows an NCL1135 point-to-point network and point-to-multipoint network.
Figure 1 NCL1135 Network Examples
Network
NCL1135
(Station)
Point-to-Point Network:
One Master and one
Station
Ethernet
NCL1135
(Master)
Network
NCL1135
(Station)
Point-to-Multipoint Network:
Up to 20 Stations per Master
NCL1135
(Station)
Ethernet
NCL1135
(Master)

Chapter 1 NCL1135 Overview
2APCD–NC003–1.0
The NCL1135 is used to extend Ethernet networks, access the Internet at high speed, connect
remote locations, and perform general data networking without the ongoing costs of leased
telephone or data lines.
The NCL1135 provides an Ethernet interface that allows you to connect to most Ethernet
networks or devices. One NCL1135 modulates and transmits data to remote NCL1135s, which
demodulate, decode, and pass the data to the receiving user network. DSSS signal
processing exploits the ability of transceivers to spread the signal information over a wide
channel bandwidth. This reduces the potential for interference with neighboring
communications systems. Because the NCL1135 operates in the microwave frequency range,
a line-of-sight communication link is required, therefore, some installations have the antenna
on rooftops or communications towers.
The NCL1135 is user-configurable and can be remotely upgraded. The NCL1135 operating
system supports simple network management protocol (SNMP) which allows for constant
status monitoring of any NCL1135 in your network.
All aspects of WaveRider’s spread-spectrum transceiver are controlled through the integration
of a powerful microprocessor. The 2.4 GHz radio transceiver allows a single NCL1135
operating in “master” mode to deliver data to and receive data from a maximum of 20
NCL1135 devices operating in “station” mode.
The NCL1135 design permits three master units to operate in close proximity without
interfering with each other. For example, three master units each supporting 20 station units
can operate in close proximity, thus establishing 60 links.

Chapter1 NCL1135Overview
APCD–NC003–1.0 3
1.2 Spread-Spectrum Radio Technology
Spread-spectrum communications systems differ from conventional narrowband
communications systems because these systems use a much larger transmission bandwidth
to send the same amount of information.
There are two primary forms of spread spectrum—direct sequence and frequency hopping.
The NCL1135 uses direct-sequence spread-spectrum (DSSS). In DSSS systems, the
transmitted information, along with a digital spreading sequence, are used to modulate the
transmit carrier. The received signal is de-spread using the same digital spreading sequence,
and the information recovered.
Although spread spectrum appears complex and uses a wider bandwidth, DSSS offers the
following advantages for its use:
• Reduced power spectral density — Spreading over a wider bandwidth reduces the
spectral density (power per Hz of bandwidth) of the transmitted signal, allowing
simultaneous operation of many spread spectrum systems in the same frequency
band and geographic area. The reduced spectral density also allows you meet the
regulatory emissions requirements in frequency bands such as the ISM band.
• Transmission security — It is technologically more difficult to surreptitiously recover
(or jam, in the case of military communications systems) spread-spectrum signals
than it is to recover conventional narrowband signals.
• Interference suppression — The same mechanism that de-spreads the desired signal
in the receiver, also spreads undesired signals, which then appears to the receiver as
lower levels of RF noise.
For more information about spread spectrum communications, contact the WaveRider
Customer Support Centre.

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APCD–NC003–1.0 5
2 Network Considerations
This section provides an overview of the network considerations that you should make before
beginning to implement an NCL1135 network. These network considerations include the
following:
• network topologies
• mode: bridging and routing
• network planning
2.1 Network Topology
The NCL1135 can be deployed in three different configurations:
• point-to-point
• repeater
• point-to-multipoint
Before configuring the system, you must determine the required network topology.

Chapter 2 Network Considerations
6APCD–NC003–1.0
2.1.1 Point-to-Point
In a typical point-to-point application, shown in Figure 2, unit A communicates directly with unit
B. You can implement the link in either bridging or routing mode.
Figure 2 Point-to-Point Application
2.1.2 Repeater
You can set up a repeater by using two NCL1135 units back-to-back.
In the configuration shown in Figure 3, unit A communicates with unit B via the back-to-back
NCL1135 repeater configuration of units C and D. You must use different frequencies for each
leg of the path. Use this configuration to circumvent large obstacles in the radio link path, or
when the link from unit A to unit B is too long to provide reasonable signal levels and data
throughput.
Figure 3 Repeater Application
In this configuration, the effective data throughput from unit A to unit B is the same as the
lessor data throughput from unit A to unit C or unit D to unit B. That is, the throughput through
a series of links will be that of the slowest link.
You can implement this configuration in either bridging or routing mode.
NCL1135 NCL1135
AB
Ethernet EthernetRadio
B
NCL1135
Ethernet Radio Ethernet EthernetRadio
ACD
NCL1135 NCL1135 NCL1135