Just as you can’t successfully construct a new building without an engineer first surveying the proposed build site, you can’t successfully install an enterprise wireless LAN without the same type of planning and evaluation. Wireless site surveys are critical tools in the WLAN planning and design process.
Site surveys can help determine the feasibility of building a wireless network in your facility, help you find the best place to position the hardware infrastructure, and even help determine the best technology to use for your application.
The process typically involves inspection and testing in the proposed coverage area; evaluation of existing power and network infrastructure; assessments of proposed operating frequencies and potential sources of interference; security exposures; and an evaluation of the applications and associated network requirements.
Below are three keys to successful wireless site surveys:
#1 Be Prepared: Wireless site surveys involve more than just a visual inspection of the facility. Before you begin, you should determine what type of survey you need and gather all the appropriate data and resources to complete the survey.
There are three types of wireless site surveys — passive, active, and predictive. A passive survey uses a software tool to evaluate signal strength, interference, and access point coverage. With an active survey, a Wi-Fi adapter is associated with the access points and exchanges packets to gather information on throughput, packet loss, and physical data rates.
A predictive survey uses planning software tools to predict what wireless coverage will look like based on floor plans. You’ll need blueprints, floorplans, or CAD files detailing the layout of the facility and building materials used. You’ll also need to know the location of power and cabling that can be used to connect the access points to the network, the location of any existing wireless equipment or nearby networks, and what types of wireless device will be used on the network.
It’s also important to delineate your goals and expectations prior to the wireless site survey. These are application dependent. Sending and receiving data to and from industrial controllers will require a different approach to network design than a solution that will involve voice or video transmission.
Determine in advance where you want wireless coverage. While full coverage is in important in areas where users will work, extending coverage to some areas (a parking garage, for instance) may not be necessary.
#2 Engage an Experienced Partner: While it’s possible for a company to perform a wireless site survey on their own for smaller, simpler installation, an enterprise deployment will require more resources and expertise.
There are several types of wireless site survey software tools you can use. For smaller installations, some of these tools can run on a single laptop. There are also more complex simulation solutions that can model an entire facility under different types of scenarios. But these software solutions are only as good as the information entered into them. Many of these solutions are not designed for industrial facilities, and those that are still need detailed data about the facility that can’t necessarily be gleaned from a CAD file. Field testing should always be part of the site survey process.
Your vendor, VAR, or systems integrator can be an excellent resource. An experienced solution provider will use a combination of simulation and on-site testing equipment to identify potential dead zones and sources of interference.
Whoever conducts the wireless site survey should do so at a time of maximum activity in the facility so that potential sources of interference aren’t overlooked. If interference is found, a spectrum analyzer can help characterize and identify the source.
#3 One Survey is Not Enough: Wireless site surveys aren’t just for installing new or upgrading existing WLANs. Once the network is up and running, you should conduct a second survey to validate network performance against the original plan.
Once the network has been running for a while, additional surveys can be used to audit the network and identify facility changes or new sources of interference. That information can be used to re-tune the equipment. In dynamic facilities like warehouses or retail stores, where staffing and stock mixes change frequently, this process can help mitigate against coverage issues that weren’t present during the initial survey.
In addition to wireless site surveys, it is important for companies to choose the ideal WLAN for their businesses. Zebra Technologies understands that the demands on a wireless network are constantly growing and changing, so their reliable WiNG Enterprise and WiNG Express solutions have been designed to easily scale as a business grows. Wireless site surveys are an important part of ensuring a WLAN is optimally designed. As more and more mission-critical applications rely on wireless communications, properly designing and maintaining the wireless network provides a foundation
