I was skeptical, but a fan does seem to help

I seem to have a new router mode that's square instead of round.  Has anyone tried a fan with this unit or found that it needed one? Mine is sitting on a top shelf near a skylight.  I actually got a faster signal with it in the attic without any windows, but if they already have heat issues, the attic is out of the question.  Also now that a number of people are using a fan for months, has any one noticed a lot of dust accumulating?  I am thinking a fan without any filtering at all might make things worse eventually. The vary porous low back pressure  filterer material  used in window AC units between the fan and the router may work well enough if it is cleaned every few months.