D-Link DWL-1800 user manual Rooftop Installation, Antennas for Outdoor Applications, Path Loss

Page 12

Path Loss

Path loss is determined mainly by several factors:

??Distance between sites – Path loss is lower and system performance better when distances between sites are shorter.

??Clearance – Path loss is minimized when there exists a clear line of sight. The number, location, size, and makeup of obstacles determine their contribution to path loss.

??Antenna height – Path loss is lower when antennas are positioned higher. Antenna height is the distance from the imaginary line connecting the antennas at the two sites to ground level. Ground level in an open area is the actual ground. In dense urban areas, ground level is the average height of the buildings between the antenna sites.

2.3.3Rooftop Installation

Rooftop installations offer several advantages:

??Fewer obstacles in the path.

??Improved performance due to greater height.

2.3.4Antennas for Outdoor Applications

The D-Link AirPremier DWL-1800 series can be used in point-to-point or point-to-multipoint configurations.

Point-to-Point

The DWL-1800B/DWL-1800R is equipped with a directional antenna. The required antenna gain depends on the required range and performance.

Point-to-Multipoint

Setting up a point-to-multipoint link requires the use of a base unit equipped with an integrated antenna and at least two remote units also equipped with integrated antennas.

7

Image 12
Contents LinkAirPremier Table of Contents Troubleshooting Guide Table of Figures DWL-1800 Point-to-Multipoint ApplicationTable of Tables Using this Guide IntroductionSystem Description GeneralDWL-1800B BU Wireless Base Unit Link AirPremier DWL-1800 Functional DescriptionDWL-1800R RB Wireless Bridge Link AirPremier DWL-1800 Compatibility and StandardsInstallation Installation OverviewPacking List Outdoor Installation Considerations General Installation Scheme Pole MountingCollocating DWL-1800 Outdoor Units Site Selection FactorsPath of Clearest Propagation Physical ObstaclesRooftop Installation Antennas for Outdoor ApplicationsPath Loss Point-to-PointUsing Outdoor Range Tables PrecautionsAntenna Polarization Cell Size/Link DistanceInstalling the Outdoor Unit Compliance with Radio RegulationsHoles/Grooves/Screw Holes Connecting the Ground and Antenna Cables Connecting the Indoor-to-Outdoor CableInstalling the Indoor Unit Brown Phase ~ Blue Neutral Yellow/green Grounding Configuring Parameters Antenna AlignmentPage Verifying Correct Operation Verifying Correct Operation of the Indoor UnitName Description Functionality Verifying Correct Operation of the Outdoor Unit What to do if the Self Test failsD-LINK Airpremier DWL-1800 Configuration Utility Installing and Running the Configuration Utility Configuration Utility ModesUnit Configuration Mode Control Window SectionTabs Section Control Window Selecting UnitsSetting the Snmp Community String Set IP Dialog BoxApplication Control Buttons Configuration Utility Tabs Station Status TabIP Parameters Tab IP Parameters Tab Snmp Parameters Tab Snmp Parameters TabCounters Tab Counters Tab BU/DWL-1800B Units?? Tx Counters ?? Rx Counters?? Link Counters ?? Resetting Counters Wlan Parameters TabWlan Parameters Tab RB/DWL-1800R Highest ChannelFrance Canada Channel FrequencyStation Control Tab Station Control TabSecurity Tab Security TabAdvanced Tab Advanced TabPage Firmware Upgrade Mode Trap Monitor TabTo upgrade firmware Firmware Upgrade Mode dialog boxFirmware Upgrade Process Advanced Tftp Settings Advanced Tftp Setup dialog boxMultiple Unit Configuration Mode Multiple Configuration Mode dialog boxResetting the Snmp Community Strings Reloading Factory Default SettingsTo reset the unit to the factory defaults System Troubleshooting Troubleshooting GuideProblem Possible Cause Corrective Action Indication Technical Specifications Configuration and ManagementSupported Standards RadioRange SecurityOutdoor Unit-to-Indoor Unit Communication InterfacesElectrical Mechanical Dimensions EnvironmentalStandards Compliance, General Appendix A. DWL-1800 FAQ GeneralDoes the DWL-1800B supports 802.1d spanning tree protocol? Collocation What is the throughput of the D-Link Air Premier DWL-1800? PerformanceCan the DWL-1800B/ DWL-1800R firmware be upgraded? FirmwareConfiguration Management What management options are available for the DWL-1800?Ethernet Connector Pin Assignments Appendix B. Preparing the Indoor to Outdoor CableAppendix C. Radio Signal Propagation IntroductionRF Terms and Definitions RF Power Level AttenuationFree Space Loss Antenna Characteristics Isotropic AntennaSystem Characteristics Link ParametersSignal Fading Link Budget CalculationLine of Sight Concept Clear Line of SightFresnel Zone Clear of Obstacles FCC Warning Avertissement AUX Utilisateurs Product Type Warranty Period What You Must Do For Warranty Service Trademarks Offices Registration Card Print, type or use block letters