Performing a Site Survey

A Site Survey is simply a study of the radio network coverage of an area. Typically someone walks the space being surveyed, collecting data samples of the radio characteristics and their location. The collected data is then used to design or optimize the location and type of radio transmitters (access points, repeaters, antenna, etc.).

The problem with most site surveying tools is that the location of a data point reading is not recorded. Just having signal strength values is not enough to determine if an area has effective coverage or where to place access points in a new installation.

Why a Site Survey is Performed

Radio wave strengths are difficult to predict. Obstacles such as walls, metal shelves, computer equipment, and even people can disturb the propagation of radio waves in unpredictable ways. The most effective method of determining the locations of access points is to physically measure radio strengths throughout the coverage area.

When to Perform a Site Survey

A site survey is usually done at four different stages of the WLAN's lifetime. Before installation, during installation, right after installation, and periodically over the WLAN's lifetime.

Pre-Installation Site Survey

Are your existing site surveying methods labor intensive and often wrong? Using VisiWave Site Survey, you can dramatically cut your time and effort and increase the effectiveness of newly installed wireless networks.

By placing one or more temporary access points in the space and then performing a quick walk through of the area, you can visualize the wireless coverage in minutes. If what you see isn't right, make some adjustments to the placement of your access point(s), quickly walk through the area again, and then immediately see the new wireless coverage.

Performing a site survey before installing a WLAN is a good practice. It allows you to start with a solid design for your wireless network. It also gives you the opportunity to discover any trouble spots and design around them. Based on the results, you may also decide that an effective WLAN is not possible for your area. A pre-installation site survey increases the likelihood of getting the installation correct the first time.

Survey During Installation

During the actual WLAN installation, a brief site survey is normally performed repeatedly to fine-tune the placement of radios.

Survey an Existing Wireless Network

After the WLAN is installed, a complete site survey should be performed to thoroughly document the WLAN coverage. This documentation is needed for both troubleshooting coverage issues and for maintaining an accurate maintenance history of the WLAN. It will also help to ensure the integrity of the WLAN coverage through always evolving environments and requirements.

Often even the best designed wireless network can perform inefficiently when actually deployed. And even small changes to an environment can have dramatic effects on radio wave propagation.

Ongoing Site Surveys

Performing regular site surveys is an essential step in maintaining well-tuned wireless networks that stay operational. Not performing regular check-ups leads to wireless networks with user complaints due to poor coverage, maintenance headaches for your support staff, and the increased risk of failure of a critical infrastructure component.