5G is short for “5th generation” technology for cellular networks, an evolution of current widespread 4G LTE standard. It began deploying worldwide in 2019 in order to be the successor to the 4G networks, just as 4G supplanted 3G. Initially, 5G will operate in conjunction with existing 4G before evolving to fully standalone networks in subsequent releases and coverage expansions. However, 4G devices are not able to use the new networks, which require 5G enabled wireless devices.
While most generations of cellular networks have technically been defined by their data transmission speeds, each has also been marked by a break in encoding methods, or “air interfaces”, that make it incompatible with the previous generation.
1G was analog cellular. 2G technologies, such as CDMA, GSM, and TDMA, were the first generation of digital cellular technologies. 3G technologies, such as EVDO, HSPA, and UMTS, brought speeds from 200kbps to a few megabits per second. 4G technologies, such as WiMAX and LTE, were the next incompatible leap forward, and they are now scaling up to hundreds of megabits and even gigabit-level speeds.
5G wireless technology brings new capabilities that enable a new kind of network that is meant to connect virtually everyone and everything together, unleashing a massive 5G IoT (Internet of Things) ecosystem where networks can serve communication needs for billions of connected devices, a truly connected world. 5G is designed to deliver higher data speeds (bigger channels), massive network capacity, more reliability, increased availability, and a more uniform user experience to more people. 5G will power innovation that would have been impossible under the 4G LTE standard.
In addition to delivering faster connections and greater capacity, a very important advantage of 5G is ultralow latency. Latency is the time taken for devices to respond to each other over the wireless network. 3G networks had a typical response time of 100 milliseconds, 4G is around 30 milliseconds and 5G will be as low as 1 millisecond. This is virtually instantaneous opening up a new world of connected applications.
How Does 5G Work?
Like other cellular networks, 5G networks use a system of cell sites that divide their territory into sectors and send encoded data through radio waves. Each cell site must be connected to a network backbone, whether through a wired or wireless backhaul connection.
5G networks use a type of encoding called OFDM (Orthogonal Frequency-Division Multiplexing), a method of modulating a digital signal across several different channels to reduce interference, which is similar to the encoding that 4G LTE uses.
The 5G NR (New Radio) air interface, alongside OFDM principles, is designed for much lower latency and greater flexibility than LTE, though. 5G also uses wider bandwidth technologies such as sub-6 GHz and mmWave (Milimeter Wave).
Like 4G LTE, 5G OFDM operates based on the same mobile networking principles. However, the new 5G NR air interface can further enhance OFDM to deliver a much higher degree of flexibility and scalability. This could provide more 5G access to more people and things for a variety of different use cases.
5G will bring wider bandwidths by expanding the usage of spectrum resources, from sub-3 GHz used in 4G to 100 GHz and beyond. 5G can operate in both lower bands (e.g., sub-6 GHz) as well as mmWave (e.g., 24 GHz and up), which will bring extreme capacity, multi-Gbps throughput, and low latency.
5G is designed to not only deliver faster, better mobile broadband services compared to 4G LTE, but can also expand into new service areas such as mission-critical communications and connecting the massive IoT. This is enabled by many new 5G NR air interface design techniques, such as a new self-contained TDD subframe design.
How Fast is 5G?
While 4G tops out at a theoretical 100 megabits per second (Mbps), 5G tops out at 10 gigabits per second (Gbps). Current 4G innovation, 4G LTE-Advanced, tops 1 Gbps downlink and 500 Mbps uplink. That means 5G is 10 to x100 faster than 4G technology — at its theoretical maximum speed, anyway.
But what makes 5G faster? The shorter the frequency and the larger the bandwidth.
The new standard will use a whole new band of radio spectrum from 4G. 5G will take advantage of “millimeter waves”, broadcast at frequencies between 30 and 300 GHz versus the bands below 6 GHz that were used in the past.
The use of shorter frequencies (millimeter waves between 30GHz and 300GHz) for 5G networks is why 5G can be faster. This high-band 5G spectrum provides the expected boost not only in speed but also in capacity, low latency, and quality.
What Is 5G DSS?
With the global 5G network rollout, mobile phone manufacturers companies are already investing in several models with support for 5G worldwide, but the problem is that these mobile networks are not yet installed in many countries.
So, in order to meet future demands for this new technology, how can service providers accelerate 5G deployment?
Typically, mobile operators acquire new spectrum to deploy new wireless technology (2G, 3G, 4G and 5G) or re-farm existing spectrum; however, both methodologies are expensive and lengthy to implement. Further, re-farming may not be a good option unless a significant subscriber base upgrade to the latest technology. So, for deploying 5G, re-farming LTE low band spectrum when the number of 5G subscribers is not large, can potentially mean capacity bottleneck for LTE subscribers, higher interference, and performance degradation to existing LTE network.
A more streamlined and efficient way to introduce 5G quickly would be dynamically assigning RF (Radio Frequency) resources between the 5G and the LTE subscribers in the existing low band LTE service area. This method can allow providers to maximize 5G coverage in a short amount of time and depending on the high throughput demand they can deploy hot spots of 5G in the higher band spectrum.
Dynamic spectrum sharing (DSS) technology is the answer to that question above.
In most cases, DSS can be deployed as a software upgrade to the existing LTE radios, it allows service providers to accelerate 5G NR deployment and expand 5G NR coverage area without significant investment in re-farming existing low band spectrum. DSS technology takes advantage of non-standalone (NSA) mode by dynamically and intelligently sharing low band LTE spectrum with both LTE and 5G NR subscribers. Additionally, NSA configuration allows control plane communication and mobile network management to be performed through the LTE infrastructure whereas the new 5G spectrum, especially in the mid to mmWave band, can be used to boost capacity for the user plane traffic.
And what is NSA?
NSA (Non-Standalone) 5G NR is the early version of Standalone 5G NR mode, in which 5G networks are supported by existing 4G infrastructure. NSA 5G NR primarily focuses on enhanced mobile broadband (eMBB), where the 5G supported mobiles will use mmWave frequencies for increased data capacity but will use existing 4G infrastructure for voice communications.
Non-Standalone 5G NR will provide increased data-bandwidth by using two new radio frequency ranges:
- Frequency Range 1 (450 MHz to 6000 MHz) — This band overlaps with 4G LTE frequencies and is called as sub-6 GHz. Bands are numbered from 1 to 255.
- Frequency Range 2 (24 GHz to 52 GHz) — This is the mmWave frequency band. The bands are numbered from 257 to 511.
Standalone (SA) 5G NR
3GPP concluded the standalone 5G NR standard in 2018, which will work alongside the Non-Standalone 5G NR standard. Standalone 5G NR will have a new end-to-end architecture that will use mmWaves and sub-GHz frequencies. This mode will not use existing 4G/LTE infrastructure.
Standalone 5G NR will use enhanced mobile broadband (eMBB), Ultra-reliable and low latency communications (URLLC) and Massive machine type communications (mMTC) to provide multi-gigabit data rates with improved efficiency and lower costs.
In other words…
DSS allows operators to use 5G with the same capacity already adopted by other technologies, such as 4G, 3G and 2G.
DSS between 4G and 5G is a focal point for mobile network operators. DSS enables the quick and cost-effective build out of robust 5G services, with broad coverage areas, using existing spectrum in mid- and low-band frequencies.
In practice, DSS is a single frequency network that can be used for the different 3G, 4G and even 5G standards. Thus, operators can define exactly which signal capacity they send over the same frequency.
5G DSS is, in fact, another technology, the non-standalone (NSA, release 15) mode of 5G NR standard for air interface. This means that 5G DSS:
- it is a new technology, which fits as 5G NR in the 3GPP standards;
- depends on the existing 4G LTE core to work, although it has dedicated carriers for the technology (as well as any 5G NSA, regardless of spectrum sharing);
- it is a 5G network that has no dedicated spectrum to work, and shares 4G, 3G and/or 2G capacity.
Technically speaking, 5G DSS is 5G indeed, because it is 5G NR technology. However, the 5G DSS is quite different from the traditional 5G, with its dedicated frequencies that deliver greater simultaneous capacity and very high speeds.
What is the difference from the 5G DSS to the “real 5G”?
Because it has shared spectrum with other technologies, 5G DSS does not deliver the full potential of a 5G network. The “real 5G” refers to a network with exclusive capacity for 5G technology — the traditional 5G.
5G DSS speeds can be greater than the 4.5G, depending on the shared capacity. But what about those very high transfer rates, in the gigabit per second range? This is restricted to the “real 5G”, with dedicated frequency.
What is the advantage of 5G DSS?
5G DSS is so much cheaper and quickly to install: there are several radio antennas from operators that start supporting the new technology with just a software update. With this, companies from all over the world will adopt the standard, as it allows a fast expansion of technology to national levels.
In addition to the technical part, 5G DSS is useful for delivering higher speeds and better user experience in locations where it is not economically viable to build a 5G network from scratch, once the existing infrastructure is used.
Finally, frequencies used by technologies such as 4G, 3G and 2G are less than 5G capacities, which allow a higher signal range compared to the 3.5 GHz and (mainly) mmWave bands. DSS will take 5G to those frequencies below 3 GHz, which remain very important to guarantee indoor environments coverage, such as buildings, houses and commercial establishments.
5G And IoT
5G will also be very important for the so-called Internet of Things (IoT). According to a study by Juniper Research, the sum of IoT connections will rise from 35 billion in 2020 to 83 billion in 2024. 4G network is unable to support the growing volume of moving equipment connected to IoT. 5G will be responsible for this task, paving the way for an increasing number of connected devices and applications such as remote surgery (telemedicine), autonomous (driverless) and connected cars, among others, in which high speed and very low latency will be needed.
A great amount of Internet-connected devices is extremely important for creating smart cities, where billions of sensors spread across the streets capture information used for the best management of cities. It is a scenario in which autonomous or semi-autonomous vehicles identify each other, intelligent traffic lights capture and share information about traffic with the traffic management authorities, sensors identify the amount of people and even their body temperatures and all this information collected in real time allows to the administration the quickly management of situations as energy consumption, traffic jams, the safety or even the control in diseases dissemination.
There is still a long way to go to popularize 5G and for its benefits to reach the world on a large scale. But its future is certain; and changes with the arrival of new services and applications extremely promising.
And What Next?
The truth is that 5G is being designed for the reality of the Internet of Things. Today, we have more and more Internet-connected smart devices, from refrigerators and microwaves, from smartwatches to wearables.
5G would be the first step to support the integration and growth of IoT, setting the stage for 6G, which, although it should only arrive around the 2030s, researchers predict that it should provide connection speeds around 1 Tb/s.
References
1. THALES GROUP. Introducing 5G technology and networks (speed, use cases and rollout). https://www.thalesgroup.com/en/markets/digital-identity-and-security/mobile/inspired/5G.
2. CHRIS HOFFMAN. What Is 5G, and How Fast Will It Be? https://www.howtogeek.com/340002/what-is-5g-and-how-fast-will-it-be.
3. QUALCOMM. Everything you need to know about 5G. https://www.qualcomm.com/invention/5g/what-is-5g
4. PC MAG. What Is 5G? https://www.pcmag.com/news/what-is-5g.
5. VIAVI. DYNAMIC SPECTRUM SHARING (DSS): THE 5G DEPLOYMENT X-FACTOR. https://blog.viavisolutions.com/2020/08/12/dss-the-5g-deployment-x-factor.
6. EVERYTHINGRF. Non-Standalone 5G-NR vs Standalone 5G NR https://www.everythingrf.com/community/non-standalone-5g-nr-vs-standalone-5g-nr.
7. CANALTECH. 5G: o que podemos esperar dessa tecnologia no Brasil. https://canaltech.com.br/telecom/5g-o-que-podemos-esperar-dessa-tecnologia-no-brasil.
