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Site Survey Tool - TamoGraph

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Introduction
Overview
System Requirements
Driver Installation
Licensing and Trial Version Limitations
Interface Overview
Access Point List
Floor Plan / Site Map
Plans and Surveys, Properties, and Options Panel
Main Menu
Performing a Site Survey
New Project Wizard
Calibration
Configuration
Data Collection
Understanding Survey Types: Passive, Active, and Predictive
Active Survey Configuration
Best Practices, Tips, and Tricks
Survey Job Splitting
Predictive Surveys
Drawing Walls and Other Obstructions
Drawing Attenuation Zones
Placing and Configuring Virtual APs
Working with Presets
Applying Visualizations
Working with Multi-floor Sites
Mixing Real and Virtual Data
Best Practices, Tips, and Tricks
Analyzing Data – Passive and Predictive Surveys
Selecting Data for Analysis
Adjusting AP Locations After Passive Surveys
Splitting an AP into Multiple Unique APs
Working with Multi-SSID APs
Visualization Types
Signal Level
Signal-to-Noise Ratio
Signal-to-Interference Ratio
AP Coverage Areas
Number of APs
Expected PHY Rate
Frame Format
Channel Bandwidth
Channel Map
Requirements
Analyzing Data – Active Surveys
Selecting Data for Analysis
Visualization Types
Actual PHY Rate
TCP Upstream and Downstream Rate
UDP Upstream and Downstream Rate
UDP Upstream and Downstream Loss
Round-trip Time
Associated AP
Requirements
Spectrum Analysis
Hardware Requirements
Spectrum Data Graphs
Performing Spectrum Analysis Surveys
Viewing Collected Spectrum Data
Exporting Spectrum Data
Reporting and Printing
Customizing Reports
Google Earth Integration
Configuring TamoGraph
Plans and Surveys
Properties
Plan / Map
Environment
Client Capabilities
Requirements
Scanner
Options
Colors and Value Ranges
AP Detection and Placement
Visualization Settings
Miscellaneous
Configuring GPS Receiver
Using GPS Configuration Dialog
Finding the GPS Receiver Port Number
Taking Photographs
Voice Control
Using TamoGraph in a Virtual Machine
Frequently Asked Questions
Sales and Support

Best Practices, Tips, and Tricks

Designing WLANs is a complex task that requires a thorough understanding of the underlying technology and design principles. If you are new to WLAN design and deployment, we strongly recommend that you read a good book on this topic, such as The Certified Wireless Design Professional Official Study Guide. Additionally, consider the following tips and tricks.

· Just because your AP's maximum output power can be set to 17 or 20 dBm does not mean that it should be set to this value. You should consider the fact that most Wi-Fi client devices, such as laptops, tablets, or desktops with Wi-Fi adapters, have a lower output power, typically 13 or 15 dBm. As a result, a client might “hear” a 20 dBm AP from a very long distance, but the AP might not “hear” the client. Additionally, APs with high output power create unnecessary interference with other APs in dense WLAN environments. If you design your WLAN for performance rather than coverage, you will probably want to have a rather dense placement of APs. Here, stronger does not necessarily mean better. You might consider lowering the power level so that it matches the power level of client devices.
· If you design your WLAN for coverage rather than performance, using high AP output power might be acceptable. However, be sure to read the AP specifications to find out the actual power level it can provide. Remember that the maximum allowed power level might be different for different channels!
· Signal level does not tell you the whole story. Consider an 802.11n AP operating in the 2.4 GHz band with the standard omnidirectional antenna and the default 17 dBm output power placed on a map with no obstructions. If you select the Signal Level visualization, TamoGraph will draw a very large (a few hundred meters) circle around your AP. Does this mean that the whole area can be considered to be covered by the AP? Of course not, because, for example, at the distance of approximately 300 meters the signal level would be about -90 dBm. Yes, the signal is there; your client device might even detect the AP and display it on the list of available networks; but there would be no connectivity. First, because the AP might not “hear” the client, as explained before. Second, even marginal connectivity requires the signal-to-noise ratio of at least 4 dBm. Considering that the typical noise level in the 2.4 GHz band in urban areas is about -90 dBm, the signal level must be at least -86 dBm. At that level, the client might be able to connect, but the throughput would be extremely poor. That said, the Expected PHY Rate or AP Coverage Areas visualizations might be much more informative than the Signal Level visualization. TamoGraph does not draw the signal level if the difference between it and the noise level is below 4 dBm.
· It is a common practice nowadays to use the 2.4 GHz band for legacy, low throughput devices and the 5 GHz band for newer, high throughput 802.11n or 802.11ac devices. When you put a dual-band AP on the floor plan, both the 2.4 GHz and 5 GHz radios are enabled by default and both are selected on the AP list on the left panel of the main application window. This means that the Signal Level or Expected PHY Rate visualizations will show you cumulative pictures; if more than one radio is included in the visualization, they will show the values for the strongest AP. However, you will probably want to estimate coverage and expected PHY rates for each band individually, because the range of 5 GHz radios is shorter and because the attenuation level for 5 GHz signals is higher. To do that, press the Select APs button on the toolbar and use the checkboxes next to the APs to select and deselect them individually. You can also group APs by band and then select or deselect all 5 GHz or 2 GHz APs with a single click. You might notice that while good coverage is available in the 2.4 GHz band in the entire area, 5 GHz coverage is not available everywhere.
· Selecting the right antennas for your AP might considerably increase signal level, decrease interference, and, therefore, improve performance. If the antennas of your APs are replaceable, this adds another degree of freedom to your WLAN design. Using TamoGraph, you can select an antenna from a large collection of generic and vendor-specific antennas. You can also view antenna patterns in 3D.