What exactly is 5G? A brief history
5G is the fifth generation of cellular mobile communications. It will ultimately replace 4G LTE to provide faster and more reliable service with lower latency. But who decides what 5G will look like?
The International Telecommunication Union (ITU) is a specialized agency at the United Nations that develops technical standards for communication technologies, and it sets the rules for radio spectrum usage and telecommunications interoperability. In 2012, the ITU created a program called “IMT for 2020 and beyond” (IMT-2020) to research and establish minimum requirements for 5G. After years of work, the agency created a draft report with 13 minimum requirements for 5G in 2017.
Once the ITU set the minimum requirements for 5G, the 3rd Generation Partnership Group (3GPP), a collaboration of telecommunications standards organizations, began work on creating standards for 5G. In December 2017, 3GPP completed its Non-Standalone (NSA) specifications, and in June 2018 it followed up with its standalone specifications (SA).
Both NSA and SA standards share the same specifications, but NSA uses existing LTE networks for rollout while SA will use a next-generation core network. Carriers are starting with the NSA specification, which means you will fall back on 4G LTE in a non-5G environment.
The standards set by 3GPP closely correspond with IMT-2020 performance targets and are somewhat complex, but here’s a general rundown:
- Peak data rate: 5G will offer significantly faster data speeds. Peak data rates can hit 20Gbps downlink and 10Gbps uplink per mobile base station. Mind you, that’s not the speed you’d experience with 5G (unless you have a dedicated connection), its the speed shared by all users on the cell.
- Real-world speeds: While the peak data rates for 5G sound pretty impressive, actual speeds won’t be the same. The spec calls for user download speeds of 100Mbps and upload speeds of 50Mbps.
- Latency: Latency, the time it takes data to travel from one point to another, should be at 4 milliseconds in ideal circumstances, and at 1 millisecond for URLLC.
- Efficiency: Radio interfaces should be energy efficient when in use, and drop into low-energy mode when not in use. Ideally, a radio should be able to switch into a low-energy state within 10 milliseconds when no longer in use.
- Spectral efficiency: Spectral efficiency is “the optimized use of spectrum or bandwidth so that the maximum amount of data can be transmitted with the fewest transmission errors.” 5G should have a slightly improved spectral efficiency over LTE, coming in at 30bits/Hz downlink, and 15 bits/Hz uplink.
- Mobility: With 5G, base stations should support movement from 0 to 310 mph. This basically means the base station should work across a range of antenna movements — even on a high-speed train. While it’s easily done on LTE networks, such mobility can be a challenge on new millimeter wave networks.
- Connection density: 5G should be able to support many more connected devices than LTE. The standard states 5G should be able to support 1 million connected devices per square kilometer. That’s a huge number, which takes into account the slew of devices that will power the Internet of Things (IoT).
Should you buy a 5G smartphone?
Although 5G will undoubtedly change the way we interact with each other and consume media, the change won’t happen overnight. It will be years before 5G is up and running smoothly across the U.S. While it’s ultimately a personal decision, it may be wise to hold off on buying a 5G handset in early 2019. In addition to the fact that coverage will likely be very spotty, the hardware will also be first-gen. With the exception of a phone AT&T plans to release at the end of 2019, most of the 5G smartphones that will come in early 2019 will likely have single-band 5G support.
Telecom giant Ericsson makes a good argument for waiting on a 5G smartphone. It reports a second generation of 5G chipsets will be announced by the end of 2019, featuring enhanced architecture and lower power consumption. You can keep tabs on which smartphones support 5G in our guide here.
Updated March 22, 2019: Revised article to reflect recent carrier changes and 5G announcements.