Around the world, the 3.5 GHz band has been tapped by operators as key mid-range 5G spectrum. In the U.S. that frequency, referred to as the Citizens Broadband Radio Service band, is set aside for LTE services. A spectrum access system, based on a three-tiered licensure system, will protect incumbents opening up the band for operators to augment capacity and for enterprises and industries to stand up private networks.