I'd imagine a simple device that broadcasts noise or fake signals would be enough to throw it off. Lots of principles used in speed trap jammers could be used.

Unless, of course, they are aware of it and try to subvert it by consciously modifying "their body shape characteristics and motion patterns".

No seriously. Maybe wear some kinda suit?

Run Ethernet throughout your home and hardwire 100% of everything. Disable all wireless radios in your house. That will stop your own gear from being used like this, but unless you turn your home into a faraday cage someone could probably blast your home with 2.4GHz externally to achieve similar results. If as you mention, perhaps you had some kind of suit that is completely absorbent to wireless spectrum, though that in itself could be used as an identifier most likely.

You can buy coating for your windows that blocks RF.

e.g. http://www.scottishwindowtinting.com/residential-window-film...

Can usually get in via custom order from anywhere that does window tinting.

What I meant was that the suit would change your "wifi fingerprint", not that it would be absorbent.

Turn the wifi hotspot on on your phone and blind it. It probably won't work so well if the background wifi signals keep moving around.

Since this uses standard WiFi, if you don't have a WiFi network, you're good!

Of metal, sure.