arduino +100Mhz radio jammer

I think your best bet would be a big ars Faraday Cage. Else you would need to create a type of frequency generator and the Arduino inst going to help you there short of using it to control timing of the generator. You need to generate a 100mhz signal that on your property would be stronger than the signal coming onto your property. Only issue is and I cant stress this enough. The FCC overrules your city and state government.