There is an eternal quality to how technology evolves. As existing areas get overworked, new frontiers open up at the fringes. Then innovators rush in to occupy the new territory before it, in turn, becomes overworked. There is an example of such a frontier today in wireless communications. IEEE’s 5G wireless initiative has the goal of serving many more users with much higher transmission speeds. But with the existing cellular bands tightly packed, where does all the required additional network capacity come from?