dennis... I hope you are still threaded to your question which I feel was worthwhile being asked, because I am still thinking about your problem.
Not being an expert on the subject, I replied with a purely personal opinion. However, I now have the thought that radio waves from any source might interfere with a broadband Router. I say this because when I installed a cable free door bell, I was getting rings without anyone pressing the push button on my front door. Obviously someone else in my area also had a doorbell operating on a similar radio frequency, so I altered the settings on mine.
Perhaps we need to wait a while until you have checked your broadband on the next occasion the Police Helicopter is in your area. In the meanwhile I would be interested to know if your Router is connected to your comp by cable or radio link.
Ron.