Yes, the wifi antennas are very specifically sized for the 802.11 frequency ranges. They also often have band pass filters built in to prevent transmissions outside of those bands, as required by FCC regulations and such. That said, if you are really interested in that kind of thing, and you are willing to switch to Linux, the wireless card drivers are very hackable.
Source: I forked the driver for my wireless card many years ago and still maintain it, tho these days it's mostly the upstream kernel driver plus a few hacks to get the most out of the hardware: https://github.com/FreedomBen/rtl8188ce-linux-driver