3 Ways Wi-Fi Design Has Evolved (Since my career began)

Offsetting Requirements, Not Devices

When I stared in 2019, our whole teams were using various "device offset" applied onto our predictive and measure surveys:

• -5 dB for for laptops

• -7 dB for phones

• -10 dB for scanners

You get the idea. Sometimes, I would get real far from the AP, where FSPL stabilizes, and take the average of forty RSSI measurements and then compare that to the average of forty measurements on my survey device. Even then I thought "gee sometimes this average fluctuates wildly, how am I supposed to design from this?" Well it turns out, there a better way to design. Recently, I was recommended Peter Mackenzie's talk here on device offsets. He discusses the nature of RF and why using static device offsets on your design isn't reliable. However if you are post-survey and want to see the perspective of a specific device having problems, then go ahead and statically offset the measured survey. As opposed to setting static offsets, simply adjust your required RSSI as needed to fulfill your design requirements. Set an offset on your measured survey if you are comparing your simulated RSSI to the RSSI measured on your survey device.

High Client Density Design with Directional Antennas

At first, I saw engineers mostly using patch antennas (~6 dBi gain) in warehouse aisles, outdoor areas, or other places where that cone shape fits quite nicely. Towards the end of my last stint as a consultant, I started to see engineers using patch antennas in clever ways. That included using patch antennas mounted facing downward in a "spotlight" fashion. Early on, I saw this used in warehouses for open areas, and in live performing venues. Fast forward to WLPC 2026, and this narrow spotlight configuration had multiple mentions:

• Jim Florwick, who has used this design for a long time, discussed the LPV approach

• Robert Boardman showed a compelling case for indoor, office use.

I'll be sure to broaden my high gain horizons for now on as they antennas are way more flexible than I thought starting out.

Co-Channel Contention NOT Co-Channel Interference

Peter Mackenzie, again leading technically in the industry, gave a webinar compelling us to stop saying co-channel interference. I've heard of this but was confused since I definitely recalled seeing co-channel interference in my CWNP books. There's an important distinction to make:

• Interference = general RF that not necessarily interpretable by the AP

• Contention = Congestion specifically resulting from STAs that speak 802.11

The former is expected for 802.11 as a "listen before talking" protocol. The latter is a potential design problem and concern for client experience. To further add to his case, Peter recommends that the word interference confuses customers as to what's really going on in their survey reports.

Conclusion

Even thought many of the fundamentals in Wi-Fi design haven't changed, these three changes have made me stop, re-evaluate, and adjust my approach to design work. As with any tech industry, we are all learning together and trying to save the world, one good RF design at a time. Despite starting 6-7 years ago, a lot has changed already and I'll be watching for more changes here on out.