I have been reading about DIY WiFI antennas & am tinkering with a waveguide-cantenna to help
improve directivity & signal-isolation for my ".11n" mode 2.4Ghz wireless bridge (~90' LOS);
which functions great ... most of the time.
the local RF enviroment is dense in AP's ( with ~2-1/2 dozen responding to polls ) and
an average of 8 interferring-AP's with signal strength's similar to the preferred AP.
Most AP's are fixed-channel, (as is my AP), but a few rogues, are using auto-channel scan feature (grrr!).
On my 1st wave-guide cantenna build, I saw noticable, apparent improvement in the relative SNR
by attenuating/reducing the interference from Wifi (co-channel, off-channel), household, spurious, etc.
metal coffee-can (D:6" x H:6-1/2"), classic can-seams
-->(flat-bottom has 3-concentric-reinforcing-rings)
USB Wifi Adapter : TP_Wn722n w/5-1/4" detachable ANT.
USB adapter's 'JACK' is poked through small hole in side of can(~1.5" from botton).
The ANT (inside can) is firmly, re-attached/screwed to 'JACK".
__ Would one expect any additional 2.4Ghz WiFi signal GAIN by
__ replacing the cantenna's "flat-bottom" with
__ an appropriate "parabolic" reflector ?
___(i.e. combine the technology of the cantenna with the developments of "WokFi"
No. parabolic antenna gain is a function of the number of wavelength widths the dish has, AKA apertures. an antenna that is ten wavelengths wide has ten apertures. cantennas are not big enough to have multiple apertures
the signals hitting the antenna in a cantenna travel different lengths before they reflect off the back and sides. this causes distortion
the signals in a dish all travel the same distance, so they reinforce each other. the dish is a better choice.