XMax Is ‘Quiet’ Broadband System

CNN takes a look at a “very quiet radio system” called XMax, aimed at broadband communications.
“What is unique about the system is that it can emit signals that are too weak to be picked up by normal antennas, but that can be ‘heard’ by special aerials which know where to ‘listen,’ thus enabling dual usage of the same scarce radio spectrum.”
CNN has the story here.