My understanding of wifi and other wireless communication such as cellphones and radio is that there are essentially two components, the frequency and the amplitude. Different frequencies allow for different signals to be transmitted at a time while an increase in amplitude allows farther range communication. If any of this is wrong please correct me.
My question is if I wanted to increase my wifi range could I simply increase the signal amplitudes on my router and device? Are there any other factors effecting the distance a signal can travel that can be easily manipulated? For example, I can't do anything about barriers such as walls and I can't make the receptors more sensitive to weak signals so those factors aren't useful to me.
Another way to increase signal strength is of course to have an intermediate device that picks up the original signal and the creates a new amplified signal. I would like to know about ways that avoid using any extra devices.