Going behind the scenes of wireless network architecture

You might be surprised how much work must be done at the blueprint level

So. You walk into an office, flip open your laptop, and connect to Wi-Fi. Sounds simple enough, right? You’ve probably got a Wi-Fi base station in your house that you set up yourself. How different could it be? How hard could it be?

Be prepared to be surprised. And informed. Because configuring a wireless network for a business office space is orders of magnitude more complex. It gets even more complex when your client is an acquisition powerhouse, continually buying up new businesses, and spaces, that require flawless, secure wireless connectivity.

This article is about one of those spaces—and how Ensunet helped it all come together.

A multi-floor—and multi-path—challenge

Wireless is all about radio waves. These need to be transmitted throughout the workspace, so they can be received anywhere, by any worker, with no dead spots. Whereas your house can be covered by a single gadget, it doesn’t work that way in an office space. And consider the space that Ensunet was tasked to configure:

We’re talking about a 20-story office building in the middle of a busy Midwest metropolis. Our client was going to be occupying Floors Three through Eight. (And not long thereafter, they’d take over the first two floors, as well.)

The interior of the building was still being built when we were called in. Some floors were closer to completion than others. It was strictly a hard-hat environment. So we had to know where future offices, cubicles, and conference rooms would go. We had to work around things like steel columns, fire stairwells, and a central elevator lobby on each floor.

It gets even trickier. This building sports a very modern design: think of its footprint as a long, wide trapezoid; in other words, each side ends in a tight, narrow point, like the bow of a ship. Lined in glass, this makes for awesome “power offices” with commanding views. When you try and get wireless into these spaces, it’s a nightmare.

Did we mention the tenants on the other floors? They’re all trying to have wireless, too. Did we mention the hotel nearby? And when we say “nearby,” we mean “just 60 feet away”! And in case you hadn’t thought of it, we’ll remind you: This hotel offers all its guests “Free Wi-Fi!”! Talk about a blizzard of interference.

Clearly, this is not a matter of “parking a base station someplace and plugging it in.”

Mapping it all out

As input, we got the architectural plans of the building. We got the intended new floor layouts from our client. We provided the client with a questionnaire, so that they could detail all of their wireless needs in advance. Then, wearing our hard-hats, we went on-site with a mobile cart, antennas, access points (base stations), spectrum analyzers, and sophisticated monitoring/mapping software.

There were two phases to our mission. First, there was what’s called the “passive survey.” Here, we literally walked the floors and recorded any transmitting device in our client’s intended spectrum space. This includes everything from the hotel’s Wi-Fi to nearby cell towers, electrical motors, even microwave ovens from tenants on other floors. All of this got mapped into our software, which we then overlaid, as a color-coded heat map, atop the floor plan.

Next came Phase Two: the “active survey.” Now it was time to use the mobile site-survey cart and its telescopic boom, to which we attached a representative access point or AP (think “base station”), raised it to the height of the future drop-ceiling, and fired it up. Then we walked the floor again, recording how the AP performed at different spots, for different frequencies and channels.

(Not to get too deep into the weeds here, but there are basically two frequency bands available for wireless: the newer 5 GHz band, which most manufacturers support with at least 21 channels, and the older 2.4 GHz band, with its three channels—in our case due to neighbor interference, the “network of last resort.”)

So we needed to figure out how many access points were required for each floor, and where to place them.

An artistic orchestration

It would be nice to say that the whiz-bang software solved all this. But it didn’t. It can’t. It takes experience and finesse to place these APs properly. Here are some of the countless considerations:

• You don’t want any AP to be too powerful. You want it to act more like a cell-phone tower, which gracefully “hands off” the signal as the user moves from one spot to another, e.g., from cubicle to conference room.

• We often had to shoot our beams through floors and ceilings in order to provide optimum signal propagation.

• We’d sometimes use the building’s steel columns to our advantage, employing them to “tune” the layout, as they can be leveraged for absorbing, bouncing, or moving signals.

The final result—our deliverable—was a schematic diagram of each floor, with each of its access points properly placed, with the proper “tuning” requirements in terms of antenna placement, radio signal transmission power, and so on.

This would, in turn, be handed off to the client’s infrastructure group, which actually did the installation and cabling, before the walls were sealed up. That’s only because this client actually has its own infrastructure group; for most other clients, Ensunet provides boots on the ground right down to the last inch of the project.

Predicting the future

There are building designers and architects who think that they can simply “draw dots” on their site plans for where a tenant’s APs should be. As you can probably surmise by now, that doesn’t work out well. When we’ve stepped in on projects like these, those same end-user designers and architects breathe a sigh of relief, because we help them avoid dings to their reputations.

This gets to the issue of “predictive modeling.” Couldn’t you, armed with the right tools and know-how, determine how to configure a wireless network without going on-site?

It’s definitely possible—albeit with a ton of caveats. To be clear: Nothing is as accurate as an actual on-site survey such as we’ve described above. That’s why we always advocate for it first. But it is possible to do predictive modeling with a reasonable degree of accuracy. You’ll need to weigh a lot of factors, including but not limited to:

• Accuracy of provided floorplans.

• Dimensions of the structure itself.

• Industry-accepted attenuation values of building materials used in the site construction. (Single example: Does that glass have an “e-glass” ceramic coating? If so, deduct 15 decibels right there. And depending on the angle you’re beaming at it, that signal might pass through, reflect, or split.). Is this accounted for in the predictive software tool?

• Transmission characteristics of the selected access points, and their specific antenna offerings.

Indeed, the client we described above was so happy with our work at this one site, that they engaged us for the same work at a dozen others. And many of these employed predictive modeling which, done right, can save both time and money. They also followed up the installation guidance with a “validation re-scan,” which measures the final installation signals to verify that they matched the design goal, and if not, provides guidance on how to correct the installation for any discrepancies.

Hopefully this article gives you a taste for what we at Ensunet call our “360° IT” approach to empowering business success. Whether you’re in the M&A space or simply the enterprise space, we’d be happy to help. Download our free M&A IT Playbook & Integration Checklist. Or contact us today for a no-obligation consultation with one of our friendly subject-matter experts