Output power is a setting in your wireless driver. Just set it to whatever is appropriate. (Getting your neighbor onboard is probably the bigger challenge.) Get

Output power is a setting in your wireless driver. Just set it to whatever is appropriate. (Getting your neighbor onboard is probably the bigger challenge.) Getting the power just right is a big part of planning large scale wifi installations. You could also put dampening (basically a resistor-like thing) in line with your antenna. There's been several proposals how to do this automatically, which would do a lot for the congestion problem you mention, for the IEEE standardization process. But I have no idea if they made it into the newer standards. Unless you actively cooperate with your neighbors, it turns into a tragedy of the commons. The one with the power regulating equipment will have worse performance to start with, but if everyone has it then everyone benefits.