User's Manual
Table Of Contents
- Contents
- Important Information
- Notices
- Description
- Installation
- Configuration
- Overview
- Accessing the Main Menu
- Configuring with the Main Menu
- Unit Identification
- Hardware/Software Revision
- System Software ROM Images
- System Current Status
- Network Configuration
- IP Filter Configuration
- RF Station Configuration
- Viewing Current RF Station Configuration
- Setting the Operating Mode
- General Equipment Setup for Performing RF Tests
- Setting Test Mode Timer Minutes
- Performing Link Monitor Test (Normal Mode)
- Performing Transmit and Receive Tests
- Performing the RSSI Test
- Setting the RF Transmit Status
- Setting the Link Monitor Period
- Setting Maximum Remote Distance (Base Station Only)
- Setting Link Monitor Remote Station Rank
- Adjusting Throttling (Remote Station Only)
- Setting Tx Power Automatically (Remote Station Only)
- Adjusting User Output Power Ceiling (Remote Station Only)
- Setting Signal Margin (Remote Station Only)
- Viewing Current Output Power Level Adjust
- Radio Module Configuration
- Viewing the Radio Module Configuration
- Setting Config Test Minutes
- Setting the Station Type
- Setting the Station Rank
- Setting the Center Frequency
- Setting Security Passwords
- Setting the Scrambling Code
- Setting the Acquisition Code
- Adjusting the Tx Power Level
- Setting a Base to Repeater Mode (Base Station Only)
- Setting System Symmetry Type (Base Station Only)
- Setting Dynamic Polling Level (Base Station Only)
- Setting Remote Unit RF Group
- Rebooting and Saving RF Module Configurations
- RF/Ethernet Statistics
- System Security
- System Commands
- Link Monitor Display
- Logout
- Setting Operating Mode with the Mode Button
- Command Line Interface
- Troubleshooting
- Appendix A: Planning Your Wireless Link
- Appendix B: Using HyperTerminal
- Appendix C: Configuring a Simple Data Network
- Appendix D: SNMP
- Appendix E: Technical Reference Information
- Appendix F: Menu Map
- Appendix G: Upgrading Software
- Glossary
- Index
Appendix A: Planning Your Wireless Link
120 AWE 120-24 Installation & Configuration Guide
Antenna Basics
Antennas focus and absorb radio energy in specific directions, depending on their design. AWE 120-24
antennas must be tuned to 2.40000 – 2.48350 GHz.
This section contains basic information about antenna parameters and how to select and install antennas for
use in your wireless system. Antenna characteristics, mounting location, and correct operation of antennas
are critical to a wireless link.
Antenna Parameters
Parameter Description
Gain • Antennas have a gain associated with them, which is a measure of their ability to
amplify signals in their tuned band
• Antenna gain is achieved by focusing the signal. A higher gain antenna has a more
compressed signal
dBd vs. dBi • Antenna gain must be measured over a known reference and is often expressed as
either dBd or dBi
• dBd is antenna gain referenced over a half-wave dipole which is an antenna that has a
donut shaped radiation pattern
• dBi is antenna gain referenced over an isotropic radiator which is a theoretical
antenna that radiates equally in all directions (e.g. the sun)
• Wi-LAN references antenna gain in dBi. The conversion factor is 0 dBd = 2.14 dBi
Beamwidth • Describes how a signal spreads out from the antenna, and the range of the reception
area
• Beamwidth is measured between the points on the beam pattern at which the
power density is half of the maximum power. This is often referred to as the –3 dB
points
• A high gain antenna has a very narrow beamwidth and may be more difficult to align
Downtilt or
uptilt
• Some antennas have either an associated downtilt or an uptilt. The tilt further
focuses the signal downward or upward with respect to the horizon
• Tilt may be either electrically built into the antenna or achieved mechanically with
the mounting gear
• Downtilt or uptilt may be required when there is a significant deviation between the
elevation of the remote site(s) and the base site
F/B • Front-to-back ratio
• Directional antennas focus the signal in a forward path. Achieved by directing the
signal in one direction that reduces the signal in the opposite direction
• A higher gain antenna typically has a greater F/B ratio