Building A Camera That Can See Wifi

From YouTube

What would it be like if our eyes could see more colors? We may never be able to answer that, but we can build devices that can do the work for us. Over the last three weeks we’ve been building a DIY radio telescope tuned to 2.44 Ghz which is right in the middle of the wifi band. With it we hoped to take a picture of a building and see all the wifi routers inside it.