Limiting AP Range for Security Purposes
Within the wireless realm, there exists many devices to boost the AP signal (repeaters, bridges etc.) Now, this may sound like an odd question, but are there devices that can limit the AP's signal strength? I'll explain why I'm asking.
Let's assume the average wireless router can transmit give or take 300 feet. Obviously there are physical ways to limit the AP range (walls, obstacles etc). Now let's say I have a small, open studio type (no walls etc) office space, that doesn't need the full 300 foot range the router provides. Let's add to that that my office is located on a main street in the downtown area situated about 20-30 feet from the main road (with windows of course)...a.k.a the perfect place for rogue sniffers driving by to try and connect to my network. Also assume I currently have all the proper security measures in place that are available for my wireless network.
Now, here's my question. Does a device exist that can actually weaken the signal around the perimeter of my office space, so that my signal won't stretch beyond the exterior of the office?
A sort of wireless 'wall' if you will. Maybe something that actually recieves the signal of my wireless router and blocks any further transmission of it to the exterior. I'm not sure how you could actually 'direct' the signal itself so that you don't loose connectivity within the perimeter. I googled around using key words like "limiting AP range" but found mostly articles relating to placing the AP around physical obstacles to prevent the full range but nothing on actual devices that can limit the AP range. Does such a device exist?