1 ms will be in the lab for years, (A First Look) From China to AT&T to the EU, regulators are being promised ultra-fast, 1 ms latency, 5G. They are being led by the nose to offer giveaways and subsidies. 1 ms. is certainly possible, as is 2 ms. LTE. But the networks being built are 5-15 ms., sometimes more. AT&T's Melissa Arnoldi has committed to a report twice a month. (Thank you.) The highlights:
- Latency of 9-12 ms. 150 meters in Waco, Texas.
- 1 gigabit 300 meters in Kalamazoo, Michigan
- Observed no impacts on 5G mmWave signal performance due to rain, snow or other weather events.
- 400 MHz signals.
These are about the results I would have expected based on experience elsewhere, but every datapoint from the field is very welcome.
AT&T engineers are hopeful of bringing the latency from tower to cell down to 5 ms. Measuring from the local intelligence is more representative of peak response. Nearly every network announced is controlling multiple cells from a C-RAN, adding 2-3 hops through routers for even favored applications. That will raise latency to 10-25 ms. for favored applications.
1 ms. from tower to cell will be part of a future specification from 3GPP, URLLC. That hasn't been released yet.
Here are confirming datapoints I've reported:
- Naked Emperors At MWC Barcelona
- LTE Latency Today 9 ms. Down to 2 ms ~2019
- Verizon 5G: "Every variable tested during the trials came out better than assumed."
- Confirmation: 28 GHz 5G 1.4 Gbps Median: 3.5 GHz 5G Massive MIMO 490 Mbps
From AT&T
Ready to Launch: How 2 Years of 5G Trials is Preparing Us for Commercial Deployment
We took our 5G show on the road. Late last year, we expanded 5G trials to more people and businesses in Waco, Texas, Kalamazoo, Michigan and South Bend, Indiana.
My team spent countless hours collecting data and talking to real people who elected to join the trial. What worked? What didn’t? What did we need to change? Why was this happening here and not there? Would mmWave spectrum really work to deliver 5G? Did we really just hit that speed in South Bend?
Waco, Texas
Participants: Small and mid-sized businesses
- Provided 5G mmWave service to a retail location more than 150 meters away from the cell site and observed wireless speeds of approximately 1.2 Gbps in a 400 MHz channel.
- Observed latency rates at 9-12 milliseconds.
- Latency impacts things like the time between pressing play and seeing a video start to stream or hitting a web link and seeing a webpage begin to load. For context, MIT researchers discovered the human brain “latency” is 13 milliseconds.
- Supported hundreds of simultaneous connected users using the 5G network.
Kalamazoo, Michigan
Participants: Small businesses
- Observed no impacts on 5G mmWave signal performance due to rain, snow or other weather events.
- Learned mmWave signals can penetrate materials such as significant foliage, glass and even walls better than initially anticipated.
- Observed more than 1 Gbps speeds under line of sight conditions up to 900 feet. That’s equal to the length of 3 football fields.
South Bend, Indiana
Participants: Small business and residential customers
- Observed a full end-to-end 5G network architecture, including the 5G radio system and core, demonstrating extremely low latency.
- Successfully provided gigabit wireless speeds on mmWave spectrum in both line of sight and some non-line of sight conditions.
