5G at Verizon and AT&T is delivering latency around 10 ms. Mei Meiyuan writes, "For 4G mode, the best round-trip radio latency is about 10ms for FDD and about 13ms for TDD model2). In theory, With short TTI, the best round-trip radio latency is about 2ms(FDD,2 OFDM symbols 8ms(TDD, 7 OFDM symbols under planning,model2)."
(Editor's note: Those measures are from the base station to the receiver. To reflect the real user experience, you must add the latency from the base station back to the relevant server. That's 20-50 milliseconds or much more. In the future, edge clouds will often reduce the combined latency to 20-30 ms total.)
Many politicians and salesmen still think 5G latency is much better than 4G latency. As the new equipment reaches the field, people will discover the difference in latency is only a few
milliseconds.
Both will be much lower than what is today in the field, but technology has advanced in 4G, not just 5G.
5G can get close to 1 ms in the lab using a short TTI, Transmission Time Interval. 4G using short TTI is only 1-2 ms longer. Short TTI was developed before 2010 and is included in the 3GPP standards for both 4G & 5G. Today's equipment, both 4G & 5G, does not support it. That will change. The illustration is from an Ericsson paper, which also has a good set of references. The fastest methods, on the left, are still in the lab.
Huawei has a goal for 4G "To be consistent with 5GNR in term of frequency utilization as much as possible."