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WiFi Site Survey

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Connect802 Is the Recognized Leader in Predictive Modeling
and On-site Survey Consulting for Wireless LAN Site Surveys
- Virtual Wi-Fi Site Survey Services Using Predictive RF CAD Modeling and Simulation -

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When circular coverage zone are predominant in your virtual wireless LAN Wi-Fi site survey - WATCH OUT!

THIS IS A BAD THING
If a virtual wireless LAN Wi-Fi site survey produces this result, you've got a problem - this is a colored topographic map of a mountain peak!

THIS IS A BAD THING
A "poker chip" design consists of fixed-radius circles of theoretical access point coverage overlaid on a building floorplan. This type of "virtual" Wi-Fi site survey creates catastrophic channel overlap in co-channel interference!

Don't Be Fooled by Simple Design Aids!

There are a number of useful products on the market to aid an engineer when they perform a wireless LAN, Wi-Fi site survey. Typically these tools will capture signal strength measurements from the access points installed at a site's wireless LAN and display the results in a graphical format. Excellent tools are available from companies like AirMagnet, Ekahau, Network General, Fluke, WildPackets, and others. When an engineer uses AirMagnet, Ekahau Planner, Sniffer Wireless, AiroPeek or other software tools they are not performing a full RF virtual wi-fi site survey. Rather, they are augmenting their understanding of the characteristics of the RF environment through measurement. While some of these manufacturers offer graphical planning tools, they will be the first to tell you that their tool should not be used to create a complete, exhaustive RF installation plan without including a visit to the site. These software tools aid in the design of a wireless LAN - they don't create a complete design.

Connect802 licenses the Motorola Enterprise Planner RF CAD modeling and simulation software. This is an engineering CAD system that grew out of the world of cell tower planning, and it is vastly more sophisticated than any of the design aid software tools from the Wi-Fi analyzer manufacturers. Connect802 provides virtual wireless LAN Wi-Fi site survey consulting services as a core business. This predictive CAD design both stands alone as a service offering and augments Connect802 Wi-Fi equipment sales.

Does the Predictive CAD Modeling System create a virtual Wi-Fi site survey in three dimensions?
Software that only considers two-dimensional space can not produce an accurate wi-fi site survey!

3-Dimensional Design With Consideration for Attenuation AND Reflection Properties

When you look at a "heat map" (coverage prediction model) produced by a wireless consultant, ask yourself this question, "Do I see generally circular or elliptical areas surrounding each access point?" If the answer is Yes, there's a fundamental problem. RF signals do not propagate outwards in circular paths unless you're in unobstructed, free space. Inside a building the signal strength is impacted by the attenuation of partitions and the reflection of signals, and the effects occur in three dimensions, not just horizontally on the floor.

An accurate predictive Wi-Fi site survey must be able to take reflection and attenuation into consideration and, unless the software being used considers the three-dimensional environment, the results will be skewed - often dramatically. Consider the fact that an access point mounted 8-feet up a wall must transmit signals that propagate downwards to service a user with a notebook computer on a desk, a wireless VoIP phone at their ear, and possibly an inventory or medical equipment cart with a client radio at some other height. The important signal paths are diagonal, coming down from the access point - not horizontal, propagating outwards at the height of the access point. Don't settle for a cheap WiFi site survey that does little more than give a generalized indication of access point placement. Get accurate results from Connect802 because we use the only full-scale, predictive RF CAD modeling and simulation software that's available for Wi-Fi design today - Wireless Valley Enterprise Planner from Motorola.)

Does the virtual Wi-Fi Site Survey that's produced have coverage patterns that show up as concentric circular enclosed areas?
RF signals don't propagate in circular zones except in free space. If you see something that looks like a topographic map of a mountain, you're not seeing a accurate representation of the signal coverage for most virtual Wi-Fi site survey situations.

What About the Other Vendor's Software Tools?

The leading tools for helping with a predictive Wi-Fi site survey each provide excellent results within the scope of their intended purpose. If you ask any of these software vendors, "Can I use this tool to determine exact access point placement without ever setting foot in the building, and will the results be accurate to within +/- 3dB?", they'll tell you "No". This is because each of these vendor's tools is an aid to the on-site wireless LAN Wi-Fi site survey engagement - not an RF modeling and simulation tool that takes signal attenuation and reflection into consideration in three dimensions..

AirMagnet Survey Pro (available for sale through Connect802)

AirMagnet Says: AirMagnet Survey stands apart from other market solutions by enabling enterprises to collect live signal, packet and spectrum data during their site surveys. This allows enterprises to simulate and measure network performance in the most scientific way possible. [Connect802 points out: This product collects live data first, then provides analysis capability]

AirMagnet Planner (available for sale through Connect802)

AirMagnet Says: AirMagnet Planner includes an Overlap feature to show where APs on the same channel overlap above a user-defined threshold. Users can also investigate any AP in detail to plot the total combined interference to a particular access point from all other Wi-Fi sources. [Connect802 points out: Planner employs basic path loss algorithms that do not incorporate the affect of multi-pathe reflection. This limits its use as a full, predictive RF CAD modeling and simulation system. Notice, too, that the coverage zones shown to the right are generally circular, which is probably not true in the real world.]

AirMagnet Planner is an excellent preliminary planning tool but it does not consider the environment in 3-dimensions and it does not take signal reflection into account. It is not possible to simulate the presence of a frequency hopping Bluetooth transmitter or the effect of an access point on another floor of a building.

Ekahau Site Survey Pro

Ekahau Says: Ekahau Site Survey Pro combines the planning, survey, analysis, and reporting capabilities into one, easy-to-use software package. The user can combine predicted and measured data in several unique, different ways. [Connect802 points out: Look at the circular coverage patterns "predicted" for this Wi-Fi site survey. Ekahau has an innovative method for triangulating the location of a Wi-Fi RFID tag and the Ekahau Positioning Engine is the single, best-of-breed Wi-Fi tagging solution in the marketplace. The Site Survey software is not, however, able to create highly accurate, 3-dimensional models for a virtual Wi-Fi site survey.

Notice the circular coverage areas. Although the software is easy to use and provides a visual approach to those needing a quick predictive wi-fi site survey, the real strength of Ekahau Site Survey Pro comes in it's post-deployment use for location tracking and post-installation site survey verification.

Aruba Networks, Cisco Systems, Trapeze Networks (RingMaster) and Other Estimation Tools

Many hardware vendors offer tools that are specifically tailored to their unique Wi-Fi solutions. These integrated site-survey estimation tools are built in to the vendors Wi-Fi wireless LAN switch equipment, or tightly integrated with their hardware in other ways. The tools perform calculations to make recommendations for AP placement, channel planning, and expected coverage. You then manipulate the results to fine-tune the design.

These tools are not comprehensive when it comes to predicting propagation through physical obstacles. The biggest benefit of these tools comes after the wireless network is deployed. At that time, post-installation verification, channel and power level assignment, intrusion detection and prevention, and general performance monitoring is built on top of the floorplan and visualized coverage maps generated by the integrated Wi-Fi site survey software tool. If you're going to deploy a sophisticated Aruba, Cisco, Trapeze, or other large-scale Wi-Fi wireless network, you must implement these types of vendor's tools to effectively manage and optimize the network on an on-going basis. [Connect802 points out: For a building that's not yet built, these integrated tools are not going to offer a complete, comprehensive, 3-dimensional virtual Wi-Fi site survey.]

Is the Predictive RF Modeling software limited to six or seven different types of construction materials?
An accurate virtual WiFi Site Survey can only be performed when a large library of specific construction materials can be assigned to individual partitions in a building.

What is a Predictive RF CAD Model?

Wireless site surveys are performed to determine correct equipment installation locations and to identify RF interference and noise issues in the environment. A manual site survey, with an engineer walking around a building, is not the way to develop an initial installation plan. That plan should be created before any on-site engagement is scheduled.

A virtual site survey, using RF CAD predictive models, starts with a building floorplan (typically an AutoCAD drawing file.) Connect802 uses the most sophisticated RF design software on the market today to format individual elements of the building so that both the attenuation and reflection radio frequency properties are considered. Predictive modeling allows the RF engineer to identify the number and placement of access points without wasting time during an on-site engagement. In addition, the types of "What If?" scenarios that can be considered in the virtual environment would require unreasonable amounts of time if attempted with real equipment during a manual site survey. Applying RF CAD modeling and simulation to the task of performing a WiFi site survey makes the wi-fi site survey process significantly more cost effective than a manual wi-fi site survey.

Why Use Connect802 For Your Virtual Wi-Fi Site Survey?

Years of Practical Experience: Since 1994, Connect802 has specialized in network system design consulting. When you need experts in wireless Ethernet, WAN/LAN networking for Wi-Fi integration, security products and Wi-Fi site survey consulting - We've Got You Covered! We are a full-service design, sales, and installation company providing wireless broadband design consulting services and product provisioning. If you need Wi-Fi for the enterprise, K-12 and higher education, hospital Wi-Fi site surveys (also for Computer on Wheels COW carts), Connect802 provides proven wireless consultants.

What Does the Industry Say About RF Site Survey Steps?

Start with a scaled floorplan. Get the blueprints and use these as the basis for any WiFi site survey project whether it's a manual site survey or a virtual Wi-Fi site survey.
Visually inspect the facility. Either perform an on-site engagement to perform tests, calibrate the predictive RF CAD model, and identify unique obstructions, or combine digital photographs of the site with help from an on-site partner who can capture RF data for later analysis using tools like AirMagnet, NetStumbler, Cognio, AiroPeek, or Sniffer Wireless.
Identify user areas. Be sure you differentiate those areas that require 802.11 coverage from those that don't. A Wi-Fi site survey that develops installation plans for an unnecessary are is not the way to produce a cost-effective design.
Determine preliminary access point locations. Do NOT draw circles on a floorplan to estimate coverage zones. Access points don't create circular coverage patterns and a Wi-Fi wireless network design that is based on a fixed radius of coverage will not work for today's advanced wireless applications like Voice-over-IP and streaming video over WLAN.
Verify access point locations. When you install the first access point, using your virtual Wi-Fi site survey as a guide, you must verify that the installation location provides the predicted level of coverage. If an RF CAD model is created as part of a virtual site survey (using the right predictive RF CAD modeling and simulation software like that from Motorola Wireless Valley Enterprise and LAN Planner) it is expected to be accurate to within +/- 3 dB. Often, the virtual RF CAD modeling software must be calibrated by on-site Wi-Fi signal strength, noise, and interference measurements to create the most accurate predictive model and virtual site survey results.
Document findings. A WiFi site survey report must fully document the findings. It's not sufficient to simply identify the installation locations for each access point. The predicted signal coverage and any actual on-site wi-fi site survey measurements must be incorporated into the system documentation.