In short, Gigabit (Category 16) LTE is 256QAM, 3×20 MHz CA, and 4×4 MIMO . The actual rated downlink speed achieved through this combination of technologies is not quite 1 Gbps, but 979 Mbps. Later we’ll discuss what sort of real-world speeds you can expect. Paired with a Cat 16. LTE will be a Cat 13.