In response to the Federal Communications Commission’s inquiry on whether it should study changes in the radio frequency noise floor, a number of commenters identified common sources of RF noise and interference that they encounter. The most common RF noise sources include:
Harmful LED lamp interference. “The solution in most cases is to replace the lamp with a different brand that does not cause harmful interference. … The bottom line is that the interference is strong enough to affect a 700/800 MHz cellular base station,” said Pericle Engineering in its FCC comment.
Large [electronic]display signs. “Two examples are the Fashion Show Mall on the Las Vegas Strip and several gambling casinos in Black Hawk, CO,” said Pericle. “The culprits here are the switching DC power supplies powering the LED lamps. Because these signs have large metal backings, they act as a reflector and focus the interfering power in one direction. At 800 MHz, harmful interference has been measured to cell sites within 100 feet of display signs while at VHF, harmful interference was measured as far as 900 feet from display signs.”