I was at the airport and noticed this wireless network security camera install. The antenna was install directly under a overhang, pointing into the overhang. This is what happens to the signal when you do this kind of installation – it deteriorates the signal quality through self multipath interference. Although these antennas are only ten degrees by eight degrees beamwidth, they are not laser beams.
The correct way to install this was to run LMR600 cable to the other end of the overhang and install the antenna at the opposite edge. The cable loss is miniscule compared to the multipath interference.