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Wireless is surpassing the number of wired connections. There are discussions about having all wireless offices to save on costs of running wires. We perform more work on laptops, tablets, and smartphones. While wireless is more prevalent and preferred by almost everyone, we must shift our mindset in deploying a wireless infrastructure that is as robust as our wired.

How do we accomplish a deployment of wireless signals in which our end users cannot see? I recommend taking a general three step approach. The first step being the most important, gather requirements from the end users. Second, analyze the wireless spectrum and perform a site survey. Lastly, verify your deployment and optimize.

Gather Requirements

The first step is listening to end user. Get in early on the planning committee if there are plans on building a new office or new office space. Get an approximation of how many devices will be using wireless. The kind of wireless devices will give you an idea of what kind of radios will be utilized.

You could be working with a classroom where iPads are used during instruction or tests. It’s possible that every student gets a Chromebook. Or maybe it’s a distribution center utilizing hand scanners for inventory and shipping.

Armed with this information, you will be able to find out the wireless capabilities of these wireless devices.

What kind of traffic are they planning to put on your wifi? Is it mostly video? Or maybe they are using wireless phones. What type of application will they be using? The answers to these questions will help you in later planning phases. You may need to take roaming into consideration. Low latency may be important. You may make a hardware decision based on the information provided to you on the information gathering phase.

What about aesthetics. For many offices, those access points may need to be hidden. You’ll need to find out where you cannot place access points. Being in the early information gathering phase will allow you to provide professional input. This is also a good time to educate the end user. This is especially true when you are planning for 5 GHz as more access points may be required. Or possibly the cost increases due to special enclosures that need to be made for pleasing the eye.

Analyze The Spectrum and Perform A Site Survey

Find any sources of interference in and around your floorspace. You may find interference from many sources such as:

  • Bluetooth
  • Radar
  • Other wireless networks
  • Wireless video tranmitters
  • Other interferers

Other tenants may be crowding the 2.4 GHz spectrum causing over utilized channels. You can use various wireless analysis tools to get this information. Analyzing the spectrum will give you a good idea of how to plan a deployment during the survey section.

Next in the process is a wireless site survey. There are a couple of ways you can do this. A predictive site survey is just that. You predict the access point placement locations based on coverage and capacity requirements. With specialized wireless survey software, you import a floor plan and the access points are placed strategically.

Another option is to perform an AP-on-a-Stick survey. Using an access point, you place it in a section of the office space, walk around with the site survey software to gather information, freeze the access point on in the software, move it to a new spot, repeat the survey, etc. This takes a lot of time and money.

In my opinion, predictive is a good start but you will definitely need to validate your installation.

This process should yield coverage information, cell sizes, and the amount of access points to meet capacity. Consider using external antennas, such as semi-directional or directional, to shape smaller cells. Omni-directional gives you less control of RF propagation.

Validate Wireless Deployment

One of the most important steps but often skipped is the validation of your wireless design and implementation. A post deployment survey is performed which validates your signal propagation, coverage, roaming, channel reuse, etc.

Most likely you will find something to optimize from your initial design recommendations.

Consider turning off 2.4 GHz radios if you have designed for 5 GHz. Ensure you are not causing issues with co-channel interference. The post deployment survey will make this visible to you.

When you are satisfied with the results, you can send it to the client for their records.

Takeaway

Wireless has the appearance of being easy. Most will just place more access points to solve their issues when they are just creating more noise on the spectrum. Begin educating end users in the requirements gathering phase. But also listen to the end users’ needs. While some wireless solutions may be at an extra cost, give them options and the drawbacks of using less than optimal design recommendations.

By gathering the requirements you get a clear understanding of the expectations of the wireless network. You then move on to learning more about the environment by visualizing the wireless spectrum. From there you begin planning and designing a wireless network based on your findings and the end user requirements. Most importantly, don’t forget to validate your design and implementation. Ensure the wireless network works as planned.



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