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Understand the basics of 5G wireless networks
To build a 5G network, the deployment mode, spectrum band and services are all important factors to understand and consider. Here's what you should know about the basics of 5G.
Wireless networking has improved significantly over the last several years, as consumers and enterprises deploy growing numbers of mobile devices, accessing new 5G fixed and mobile networks.
Commercial 5G wireless networks first launched on a widespread scale in 2019. Since then, mobile network operators (MNOs) have been working to expand the coverage of this new high-speed, low-latency cellular standard.
What is 5G?
The 3rd Generation Partnership Project (3GPP) launched the first 5G New Radio (5G NR) specification as part of its Release 15 in 2017. From its initial commercial launches, 5G exceeded real-world 4G download speeds. Actual 5G speeds depend on the frequency the technology uses, such as low-band, midband or high-band.
High-band 5G ranges from 24 GHz to 39 GHz and uses millimeter wave (mmWave) spectrum. High-band 5G can deliver data speeds of more than 1 Gbps but only if the user is outdoors and up to a range of 1,000 feet from a mobile 5G mmWave base station. Users need to be located near a 5G base station or small cell to receive sufficient mobile coverage.
Carriers supply much of the world with midband spectrum -- ranging from 1.7 GHz to 4.7 GHz -- which enables download speeds over 100 Mbps and a signal coverage range of several miles. The three major MNOs in the U.S. have used low-band 5G to blanket large areas, delivering data speeds only slightly over 50 Mbps. Nevertheless, low-band is still faster than the 20 Mbps average download speeds offered by 4G LTE.
Another important technical 5G capability is low latency. Network response time -- the length of time it takes for a packet of data to reach its destination -- is around 70 milliseconds (ms) for 4G LTE in the best circumstances. The response time for a true 5G network can be as low as 10 ms to 20 ms.
The majority of 5G networks currently operational, however, aren't true 5G networks. Most 5G networks are non-standalone (NSA), which means they connect the radio access network (RAN) elements of 5G to a 4G core to control routing, forwarding and user mobility functions. NSA networks represent the majority of 5G currently available worldwide.
The standalone (SA) specification -- which uses a 5G core and RAN -- was completed in June 2018, but few MNOs have yet to implement it. As it stands, T-Mobile is the only major U.S. MNO to roll out SA, while China Mobile, China Telecom and China Unicom have deployed SA in China.
A few more operators worldwide have deployed SA, but most interest in SA is coming from enterprises looking to deploy private 5G networks in corporate factories and facilities. Companies can use the low latency delivered by private networks for applications like indoor critical communications and industrial robotics.
Types of 5G wireless network services and how they work
MNOs have currently rolled out two types of 5G services: fixed wireless access (FWA) and mobile 5G. Here's how the two types of 5G wireless network services work.
Fixed 5G wireless broadband
Fixed wireless broadband is a set of services designed to deliver last-mile internet connectivity to a business or residence using radio signals rather than a wired connection directly to the premises. To provide fixed wireless broadband, carriers deploy 5G radios in base stations or small cell sites, such as on streetlights and telephone poles.
5G radios deliver signals to wireless modems installed inside buildings and residencies, replacing the need for fiber, cable or other wireline connections. FWA services are based on midband or mmWave 5G. FWA services often deploy a repeater to extend the range of fixed services from a small cell or base station to a user's home.
In December 2017, 3GPP completed standards for the 5G NR required for fixed broadband wireless. Verizon and T-Mobile are the main exponents of FWA in the U.S., along with several smaller operators and startups.
5G mobile services
MNOs initially deployed NSA mobile 5G services in 2019, but major MNOs in North America, Europe and Asia have only recently begun to approach nationwide coverage for mobile 5G. Data speeds differ greatly, depending on what type of frequency the mobile 5G supports.
5G wireless networks in the enterprise
The full promise of 5G technology for enterprises is starting to emerge for companies now that commercial private 5G networking is taking off. IDC recently reported that private 5G is coming into limited commercial availability in 2022.
"Most private 5G projects to date remain as either trials or pre-commercial deployments," IDC said. "While private 5G remains in its infancy from a market size perspective, the appetite and interest for what it can deliver is very real."
Companies planning to roll out private 5G networks will need RAN hardware -- small cells or a base station -- 5G core software and devices that work on the chosen frequency. Gaining access to radio spectrum is one of the most difficult aspects of a private network deployment.
In the U.S., companies can use Citizens Broadband Radio Service (CBRS) midband spectrum for 5G private networks. In parts of Asia and Europe, governments allocate spectrum for private network use. Many webscale IT companies, such as Amazon and Cisco, are starting divisions dedicated to deploying private networks. Mobile and cable operators are also looking to get in on the act.
For example, Comcast paid $495 million to acquire 830 CBRS Priority Access Licenses, which it can assign for private networking across the country. Verizon has also struck global deals on private networking. The operator joined the space in April 2021 after signing an agreement to provide the Port of Southampton in the U.K. with a private 5G network connection.
Service providers are driving 5G development
5G is now available in much of Asia, Europe and North America, as well as some countries in Africa. In December 2021, Ookla, an internet performance metric analyst company, reported that the U.S. had the highest availability of 5G at 49.2%, followed by the Netherlands with 45.1% and South Korea at 43.8%. Ookla added that Seoul, South Korea, offers the highest median 5G download speeds at 530.83 Mbps, followed by Oslo, Norway, at 513.08 Mbps.
In the U.S., much emphasis is on using midband spectrum for current deployments. AT&T said it will cover 70 to 75 million people with C-band by the end of 2022. T-Mobile said in April 2021 that it expects to cover 250 million people in the U.S. with its 2.5 GHz spectrum by the end of 2022. Meanwhile, Verizon announced it expects to cover 175 million people with its C-band spectrum by the end of 2022. This is in addition to high- and low-band 5G rollouts already undertaken by the major U.S. MNOs.
This article was originally written by Jean DerGurahian and expanded by Dan Jones to reflect developments in 5G technology and deployment.
