Every manufacturer uses different antenna designs and signaling characteristics for this type of gear. Back in the early days of the company, they would program the units in the office. For a few manufacturers, when their unit was switched on inside the office everyone within 50 feet or so would immediately know it, even if you were in the next room over and could not see that someone was working on those units. Those units were promptly discarded in favor of other designs because people would be ready to throw them out the window or simply leave the office in short order.
As I stated, before this experience I would not have believed it, but when the worst of that 2-5 GHz RF gear was turned on, everyone within a certain distance immediately had an unpleasant experience. It is hard to describe -- kind of like someone was suddenly scrubbing the inside of your brain with sandpaper. An extremely irritating experience that definitely impairs cognitive function and is unlike any other experience I've had. Fortunately, most RF gear in that spectrum has no immediately discernable impact on people, though a larger group of devices has a subtle impact, mild headache being a common symptom of proximity to one of those devices.
There definitely is some kind of effect from RF gear in the 2-5 GHz spectrum, even at relatively low power, though it appears to be as much a function of the antenna design and signal characteristics as anything. The puzzling thing is that while the Europeans have done studies that show that exposure to these frequencies leaves only scant biochemical traces in people, in blind studies people exposed to the RF had clear psychological reactions to that exposure that has never been adequately explained.
"I used to believe this was a lot of nonsense, right up until the point that I was a principle at a startup that was doing Layer-2 fixed wireless."
Wireless phone technology is the exception to the rule - most of these complaints have little basis in fact - the people making the complaints have no concept of the 1/r^2 or 1/r^3 relationship that dramatically drops the fields over distance.
But people putting cell phones to their ear and people standing next to transmitters are getting significant effects.