Qualcomm promises gigabit LTE speeds with its new Snapdragon X16 modem

Most recent LTE speed increases have come via carrier aggregation, which essentially combines multiple chunks of spectrum across multiple antennas to improve bandwidth. Most of today’s high-end phones use two or three chunks of 20MHz spectrum to achieve download speeds of up to 300 or 450Mbps, respectively. The Snapdragon X12 achieves its 600Mbps speeds by using three chunks of 20MHz spectrum plus a higher 256-QAM rather than 64-QAM, increasing the amount of data that can be transmitted over the same link from 75Mbps to 100Mbps (albeit at the cost of higher interference). The X16 uses a combination of technologies to hit its 1Gbps theoretical peak. – Andrew Cunningham, Ars Technica