5G IoT Connectivity & Communications

5G is still being defined, but it is expected to arrive in 2020 and eventually be able to handle roughly 1,000 times the amount of mobile data as today’s networks. Image courtesy of National Instruments.

It wasn’t too long ago that the switch from 3G wireless networks to 4G LTE technology was looming. 4G adoption in the U.S. now stands at 20%, according to Juniper Research, but a lot of regions still rely primarily on 3G connections, and many machine-to-machine (M2M) solutions use 2G cellular technology.

But even though 4G usage isn’t expected to hit 30% until around 2020, the next iteration is already in development. Various industry and standards bodies are working to define fifth-generation (5G) networks, and unlike the move from 3G to 4G (which primarily increased speed and bandwidth), the next shift could require major changes to the network infrastructure. It will also open up new possibilities for designers of connected devices that will be part of the Internet of Things (IoT).

5G is expected to arrive in 2020, and be able to handle roughly 1,000 times the amount of mobile data as today’s networks (about 10Gb/s). With 5G, users will see an increased data rate, reduced end-to-end latency, improved energy efficiency and better coverage.

“One thing that 5G is trying to do is address some of the deficiencies in current networks; it’s not just focused on increasing data rates,” says James Kimery, director of marketing for the 5G, RF and software defined radio group at National Instruments (NI). “It’s not just about having a great Netflix experience on a smartphone. This will really open our eyes to what wireless can do for a number of different applications.”

Another benefit of 5G is its potential for stronger, vaster coverage. “One problem with cellular network performance is that it degrades at the edge of the network. 5G can solve that problem,” says Ken Karnofsky, senior strategist at MathWorks. “Another issue is machine-to-machine communications, which take a number of forms. As you get sensing devices and machines communicating with each other, there are different network considerations that need to be taken into account.”

Those improvements will be critical for applications like connected cars and for IoT devices that are expected to send large amounts of data on a consistent basis to enable real-time visibility. These devices may also communicate with each other over the cellular network, in addition to via Wi-Fi or Bluetooth links.

The move to 5G will also require an adjustment for designers, who will need different types of design skills to develop products with software-defined radios, including RF (radio frequency) design, system architecture, digital signal processing, software development and digital hardware specialists all working in close concert with one another.

“There are new considerations,” Karnofsky says. “To optimize the system, the digital algorithm and RF and analog folks usually had different backgrounds and worked with different tools. Engineering teams can’t do that anymore.”

To accommodate the potentially billions of new devices joining the network via the IoT, researchers are investigating non-orthogonal multiple access scenarios so that many more end devices can share the same bandwidth. Latency also has to improve, because many of the potential IoT applications require direct remote control of devices over the network with real-time response rates.

“If you are trying to control a machine, or you have sensor data and you want to add control to that application, the networks have to be responsive,” Kimery says. “For the true IoT experience, latency is one big thing that has to be addressed.”

However, 5G is still in the very earliest stages of development—there are still disagreements in the wireless industry about exactly what 5G should be and do.

“It’s a very future-looking concept, and there are no industry standards implemented yet,” says Brian Daly, director, Core Network and Government/Regulatory Standards at AT&T. “Initial standards are expected to be unveiled through 2018, and relevant standards involving rich set of features will come in 2020 and beyond.”

Still, the industry is moving out of the research phase and into building prototypes of potential 5G solutions. “We’ve seen a dramatic uptick in activity in the past year,” Karnofsky says. “The race is on to not only define what the standard will look like, but also to get the IP (intellectual property) defined that will be part of that standard.”

A New Type of Network

Whatever form it takes, 5G is expected to enable more flexible mobile solutions. “A concept being discussed is mobility on demand, where you tailor the mobility needs of the devices based on the context of the services the device is supporting,” Daly says. “5G will also enhance efficiency by better supporting short burst communications, like you find with the IoT.”

Context information will also be known to the network, which allows the network to determine how many resources need to be allocated to an end device within the context of the operator’s policies. That’s a much different approach than is used currently, and will change the way that end devices and network infrastructure interact.

Getting there will involve the development and adoption of new technology. There’s no single technology that will enable 5G; a combination of innovations will make this faster, more responsive network possible, and they are at varying stages of development right now. The key technologies include:

New waveforms: Research is underway to increase the efficiency of existing networks by getting more bits per hertz. New 5G waveforms are probably one of the furthest along of all these technologies, and could be rolled out in the near future, according to Kimery.

Densification: In this case, increased network coverage would be using macro cells, small cells and pico cells. Adding more access points to a service area can create geographic division of the spectrum, thus improving efficiency. Densification is a technique that is already being tested in a limited sense around the world.

“Densification doesn’t solve latency or power challenges, but it does address the issue of increased capacity and provides some data rate improvement,” Kimery says. “It can be rolled out sooner than later, and then combined with these other technologies.”

Massive MIMO (multiple input, multiple output): Massive MIMO can provide more bandwidth and energy efficiency. Massive MIMO base stations use hundreds of antenna elements to focus signal energy on a user. NI is working with several universities on this concept.

“If you have more antenna elements in the same base station, you can guide the energy more efficiently than just blasting waves all over the spectrum,” Kimery says. “You transmit with less power, but you get faster data rates.”

Millimeter Wave (mmWave) Communications: Spectrum below 6GHz is in short supply, and a dramatic reallocation in the near future is not likely, so researchers have turned their attention elsewhere to the more challenging environment of millimeter wave frequencies. Use of shorter, millimeter wavelengths can provide more spectrum bandwidth (28GHz, 38GHz, 71-76GHz). Nokia has prototyped a mmWave communication link that can produce data rates of 100 times 4G.

“At those frequencies, you don’t have to move, or beg or borrow to free up continuous spectrum,” Kimery says.

The shift to mmWave technology would require significant changes for both the base stations and handsets or connected devices to use a different part of the spectrum. Until recently, mmWave was considered a non-starter when it came to cellular communications, and significant work remains to commercialize it.

There are other advancements in the works as well. “It’s premature to draw real conclusions, but there is a lot of talk about the virtualization of the network, having more software-defined architectures, and using open source solutions in a virtualized environment,” AT&T’s Daly says. “That represents a fundamental change in the architecture.”

Impact on Wireless Design

Designers wondering how this will affect connected products will likely have to wait a while to see how the standards development process shakes out, and how the enabling technologies are rolled out.

There will be a number of advantages, though. In the case of millimeter wave spectrum, the higher the frequency, the smaller the antenna becomes. Product designers can have more flexibility about how the antenna is incorporated into the device.

With more responsive networks, designers will no longer have to accommodate for latency in the design of a connected product. “Most IoT device designers have to solve that problem locally,” Kimery says. “Because latency is unpredictable, you have to accommodate that locally. For that to be pervasive, it has to be built into the network.”

Power savings will also be an important improvement. IoT devices will need long-lasting batteries. 5G improvements can make the network and the devices connected to it more energy efficient. New 5G waveforms could improve battery life significantly.

For embedded designers, antenna placement and power use will be critical areas in 5G. “Where do you place the antenna, and can you come up with clever algorithms to compensate for the fact that the antenna won’t always be in the perfect place?” Karnofsky says. “Low power is another consideration, so which technology is used will depend on how quickly that evolves for lower power types of operation.”

IoT devices may provide small amounts of data in short bursts, or provide a continuous feed. A key element of 5G will be how the network serves those types of mixed-use requirements. “We need to provide higher data rates and reduced latency to accommodate certain functions, and there are devices that will require battery life that lasts years or tens of years,” Daly says.

“Providing mobility is a really important part of what the specification and use cases are really geared toward,” he says. “We want to make sure we build in the security levels to defend against security threats; we have to cope efficiently with high mobility scenarios, inside connectivity, and even high-speed train applications.”

For the core physical layer components of the network, designers will have to deal with different ways of modulating the signal, and the interaction between the RF and digital parts of the design will be more and more important. “Companies will need to appreciate and understand the adjacent areas of expertise, and they will need teams staffed with those different areas of expertise, or tools that can help them compensate for that,” Karnofsky says.

Another element of interest to designers will be how network signaling is affected by context awareness in the network, and how the device and network will communicate with each other in the future depending upon the application.

MathWorks has already worked with a number of companies that are testing and simulating new waveforms and modulation methods like massive MIMO using its MATLAB tool. “In the past, RF simulation was done in circuit-level simulation, separate from digital simulation,” Karnofsky says. “You can use the MATLAB base programming for the digital piece, and high-level graphical simulation for the RF piece in a single simulation.”

For designers looking ahead to product development in the post-2020 timeframe, it will be important to research these new enabling technologies, and follow their development. “5G will have an impact on the full ecosystem: the air interface, transport, device, core ... It will touch everything within that ecosystem,” Daly says. “In order to understand the direction of 5G, it is important to understand each of those touchpoints.”

More Info

• AT&T
• National Instruments
• MathWorks
• Next Generation Mobile Networks