LTE can operate on a wide range of radio frequency bands, which will allow many mobile carriers to switch over to LTE without starting from scratch [source: 4G Americas]. The migration has already begun: 4G LTE is operating in many U.S. and European cities in 2013 [source: Osborne]. It doesn't require a new phone. LTE can operate alongside 2G and 3G networks, and multi-mode phones can access any of them, using LTE where it's available and, say, HSPA where it's not