Fifth-generation wireless (5G) is the latest iteration of cellular technology, engineered to greatly increase the speed and responsiveness of wireless networks. With 5G, data transmitted over wireless broadband connections can travel at multigigabit speeds, with potential peak speeds as high as 20 gigabits per second (Gbps) by some estimates. These speeds exceed wireline network speeds and offer latency of 1 millisecond (ms) or lower for uses that require real-time feedback. 5G will also enable a sharp increase in the amount of data transmitted over wireless systems due to more available bandwidth and advanced antenna technology.
5G networks and services will be deployed in stages over the next several years to accommodate the increasing reliance on mobile and internet-enabled devices. Overall, 5G is expected to generate a variety of new applications, uses and business cases as the technology is rolled out.
How does 5G work?
Wireless networks are composed of cell sites divided into sectors that send data through radio waves. Fourth-generation (4G) Long-Term Evolution (LTE) wireless technology provides the foundation for 5G. Unlike 4G, which requires large, high-power cell towers to radiate signals over longer distances, 5G wireless signals will be transmitted via large numbers of small cell stations located in places like light poles or building roofs. The use of multiple small cells is necessary because the millimeter wave (MM wave) spectrum-- the band of spectrum between 30 gigahertz and 300 GHz that 5G relies on to generate high speeds -- can only travel over short distances and is subject to interference from weather and physical obstacles, like buildings or trees.
Previous generations of wireless technology have used lower-frequency bands of spectrum. To offset the challenges relating to distance and interference with MM waves, the wireless industry is also considering the use of a lower-frequency spectrum for 5G networks so network operators could use spectrum they already own to build out their new networks. Lower-frequency spectrum reaches greater distances but has lower speed and capacity than MM wave.
The lower frequency wireless spectrum is made up of low- and midband frequencies. Low-band frequencies operate at around 600 to 700 megahertz (MHz), while midband frequencies operate at around 2.5 to 3.5 GHz. This is compared to high-band MM wave signals, which operate at approximately 24 to 39 GHz.
MM wave signals can be easily blocked by objects such as trees, walls and buildings -- meaning that, much of the time, MM waves can only cover about a city block within direct line of sight of a cell site or node. Different approaches have been tackled regarding how to get around this issue. A brute-force approach involves using multiple nodes around each block of a populated area so that a 5G-enabled device can use an air interface -- switching from node to node while maintaining MM wave speeds.
Another approach -- the more feasible one -- for creating a national 5G network is to use a combination of high-, medium- and low-band frequencies. MM wave may be used in densely populated areas, while low- and midband nodes may be used in less dense areas. The low-band frequencies can travel longer and through different objects. One low-band 5G node can stay connected to a 5G-enabled device for up to hundreds of square miles. This means that an implementation of all three bands will give blanketed coverage while providing the fastest speeds in the most highly trafficked areas.
How fast is 5G?
5G download speeds can currently reach upwards of 1,000 megabits per second (Mbps) or even up to 2.1 Gbps. To visualize this, a user could start a YouTube video in 1080p quality on a 5G device without it buffering. Downloading an app or an episode of a Netflix show, which may currently take up to a few minutes, can be completed in just a few seconds. Wirelessly streaming video in 4K also becomes much more viable. If on MM wave, these examples would currently need to be within an unobstructed city block away from a 5G node; if not, the download speed would drop back down to 4G.
Low band can stay locked at 5G over longer distances, and even though the overall speed of low-band 5G may be slower than MM wave, low band should still be faster than what would be considered a good 4G connection. Low-band 5G download speeds may be up to 30 to 250 Mbps. Low-band 5G is more likely to be available for more rural locations. Midband 5G download speeds may reach up to 100 to 900 Mbps, and it is likely to be used in major metro areas.
Benefits of 5G
Even though the downsides of 5G are clear when considering how easily MM waves can be blocked, or less clear considering radio frequency (RF) exposure limits, 5G still has plenty of worthy benefits, such as the following:
- use of higher frequencies;
- high bandwidth;
- enhanced mobile broadband;
- a lower latency of 1 ms;
- higher data rates, which will enable new technology options over 5G networks, such as 4K streaming or near-real-time streaming of virtual reality (VR); and
- the potential to have a 5G mobile network made up of low-band, midband and MM wave frequencies.
When will 5G launch?
Wireless network operators in four countries -- the United States, Japan, South Korea and China -- are largely driving the first 5G buildouts. Network operators are expected to spend billions of dollars on 5G capital expenses through 2030, according to Technology Business Research (TBR) Inc., although it is not clear how 5G services will generate a return on that investment. Evolving use cases and business models that take advantage of 5G's benefits could address operators' revenue concerns.
Simultaneously, standards bodies are working on universal 5G equipment standards. The 3rd Generation Partnership Project (3GPP) approved 5G New Radio (NR) standards in December 2017 and is expected to complete the 5G mobile core standard required for 5G cellular services. The 5G radio system is not compatible with 4G radios, but network operators that have purchased wireless radios recently may be able to upgrade to the new 5G system via software rather than buying new equipment.
With 5G wireless equipment standards almost complete and the first 5G-compliant smartphones and associated wireless devices commercially available in 2019, 5G use cases will begin to emerge between 2020 and 2025, according to TBR projections. By 2030, 5G services will become mainstream and are expected to range from the delivery of VR content to autonomous vehicle navigation enabled by real-time communications (RTC) capabilities.
In the United States, there are already some networks being developed in select cities. Currently, Verizon is offering MM wave 5G at certain locations in select cities, including Atlanta; Boise, Idaho; Boston; Chicago; Dallas; Detroit; Houston; New York; Providence, R.I.; and Washington, D.C. As time passes, Verizon will add more cities to its 5G network, such as San Diego and Kansas City, Mo. T-Mobile's 5G network includes locations within Atlanta, Cleveland, Dallas, Las Vegas, Los Angeles and New York.
What types of 5G wireless services will be available?
Network operators are developing two types of 5G services:
- 5G fixed wireless broadband services deliver internet access to homes and businesses without a wired connection to the premises. To do that, network operators deploy NRs in small cell sites near buildings to beam a signal to a receiver on a rooftop or a windowsill that is amplified within the premises. Fixed broadband services are expected to make it less expensive for operators to deliver broadband services to homes and businesses because this approach eliminates the need to roll out fiber optic lines to every residence. Instead, operators need only install fiber optics to cell sites, and customers receive broadband services through wireless modems located in their residences or businesses.
- 5G cellular serviceswill provide user access to operators' 5G cellular networks. These services began to be rolled out in 2019 when the first 5G-enabled (or -compliant) devices became commercially available. Cellular service delivery is also dependent upon the completion of mobile core standards by 3GPP.
5G vs. 4G: Key differences
Each generation of cellular technology is separated by not just its data transmission speed, but also a break in encoding methods, which require end users to upgrade their hardware. 4G can support up to 2 Gbps and is slowly continuing to improve in speeds. 4G featured speeds up to 500 times faster than 3G. 5G can be up to 100 times faster than 4G.
One of the main differences between 4G and 5G is the level of latency, of which 5G will have much less. 5G will use orthogonal frequency-division multiplexing (OFDM) encoding, similar to 4G LTE. 4G, however, will use 20 MHz channels, bonded together at 160 MHz. 5G will be up to between 100 and 800 MHz channels, which requires larger blocks of airwaves than 4G.
Samsung is currently researching 6G. Not too much is currently known on how fast 6G would be and how it would operate; however, 6G will probably operate in similar differences in magnitude as between 4G and 5G. Some think 6G may use MM waves on the radio spectrum and may be a decade away.
5G use cases
5G use cases can range from business and enterprise use to more casual consumer use. Some examples of how 5G can be used include the following:
- streaming high-quality video;
- communication among devices in an internet of things (IoT) environment;
- more accurate location tracking;
- fixed wireless services;
- low-latency communication; and
- better ability for real-time analytics.
In addition to improvements in speed, capacity and latency, 5G offers network management features -- among them network slicing, which enables mobile operators to create multiple virtual networks within a single physical 5G network. This capability will enable wireless network connections to support specific uses or business cases and could be sold on an as-a-service basis. A self-driving car, for example, could require a network slice that offers extremely fast, low-latency connections so a vehicle could navigate in real time. A home appliance, however, could be connected via a lower-power, slower connection because high performance is not crucial. IoT could use secure, data-only connections.
Who is working on 5G?
Many of the big carriers are working on building up their 5G networks now. This includes Verizon, AT&T and Sprint. Verizon is working on implementing MM wave, and T-Mobile is working on low- and midband 5G first.
Led by T-Mobile, carriers are starting to embrace the idea of a multi-tier 5G strategy, which includes the use of low-band, midband and MM wave frequencies. T-Mobile has started to launch 5G in half a dozen markets currently.
Verizon is another leader in the 5G market and is currently focusing on the implementation of MM wave 5G. In addition, Verizon created an investment fund named Verizon Ventures. Verizon Ventures aims to invest in areas that would benefit from 5G, such as augmented reality (AR), IoT and artificial intelligence (AI).
Sprint is also offering midband 5G using 2.5 GHz frequencies. AT&T has started investing in 5G but is currently lagging behind the competition a bit. The company has also rolled out 5G Evolution (5GE), which is not actually 5G.
Why 5GE is not really 5G
AT&T has released a 5GE network, and in an update, 4G LTE users have gotten an "upgrade" to 5GE. However, 5GE is just a rebranding of AT&T's Gb 4G LTE network. AT&T argues that the speeds are close enough to 5G, but it is technically not 5G. The G stands for generation, typically signaling a compatibility break with former hardware. 5GE does not follow this trend and is technically not 5G. This marketing strategy may mislead individuals who do not know 5GE is not actually 5G.
What 5G phones are available?
A phone or another piece of hardware can't just get a software update on a 4G phone to enable 5G. 5G requires specific hardware. To be able to utilize 5G, a user must have a device that supports 5G, a carrier that supports 5G and be within an area that has a 5G node within range.
Some examples of 5G enabled phones include the following:
- Samsung Galaxy S10 5G
- Samsung Galaxy Note10+ 5G
- Samsung Galaxy A90 5G
- OnePlus 7 Pro 5G
- Moto z3
- Xiaomi Mi MIX 3 5G
- Huawei Mate X
- Huawei Mate 30 Pro 5G