The number of connected devices — from phones to cars to clothes — is set to explode. All of this stuff depends on radio signals moving back and forth between devices. Problem is, with so many of these transmissions crowding the airwaves, a lot of them could get lost to interference. To fix the coming crunch, federal regulators think they’ve come up with the right solution: Give companies like Verizon and AT&T a lot more frequencies on the wireless spectrum to play with.