Advertising from today’s cellular service providers would understandably make the common layperson assume communication technology is now in the age of 5G—that it’s here and being rolled out to the masses. But ask any electronic test & measurement engineer about the state of 5G, and they’ll likely tell you that we’re still almost a year from seeing widespread 5G adoption in various industries.
As we enter the final year of this decade, we at Evaluation Engineering wanted to get input from T&M vendors on what they see as where 5G is now in its development, and what developments they expect to see throughout 2019. Here, Analog Devices director of wireless technology Tom Cameron and OnScale CEO Ian Campbell weigh in on a number of 5G topics.
Campbell:
The 5G Hype—Addressing the disconnect between 5G network availability and devices that must be created to exist on the network: The Big Network giants of the world—AT&T, Verizon, Vodafone—are advertising their latest 5G trial results and although some results are impressive, you may get the impression that 5G is already here, or at the very least, right around the corner. On the other hand, if you talk to your average mobile RF Front-End (RFFE) engineer, he or she might tell you that true mobile applications of 5G technology are still a few years away.
The discrepancy lies in the disconnect between 5G network availability and the devices that must be created to exist on that network. The Big Network providers are racing to replace an entire wireless infrastructure, an immense challenge in itself. And while they fiercely compete to build the backbone needed to support 5G, another major piece of the puzzle is engineering mobile devices that are 5G compatible and can live on the new network. The major caveat to these 5G trials are that the cell companies are using 5G base stations to transmit data to bulky 5G routers, not 5G smartphones or other mobile devices. Until we can miniaturize RF front-end (RFE) components so that we can squeeze bulky form factors into a shiny new 7 mm thick iPhone and create a day-to-day usage scenario, 5G will continue to remain more of a marketing hype than a reality.
Where engineers are now with optimizing/miniaturizing the performance of the components that go into 5G devices and what they need to overcome this challenge: Engineers will be working nonstop over the coming months and years to make 5G mobile devices a reality. They will be perfecting each component along the RFFE signal chain, which includes antenna arrays, beamforming algorithms, filters, switches, power amps, and more.
A key challenge that engineers face developing 5G mobile devices, like smartphones, is miniaturizing and optimizing the performance of the radio frequency front end. The RF front-end module consists of filters, amplifiers, and switches to manage gigahertz RF signals. Filters for 5G bands are especially challenging to optimize and in a 5G smartphone, there will be dozens of these tiny filters. For context, the miniaturization of filters was largely responsible for the leaps from 1G to 2G, 2G to 3G, and 3G to 4G. New filter technologies like SAW and FBAR made these leaps possible, and we’ll need another step-change in filter technology to enable 5G bands up to 6 GHz, and an even larger jump to get to the fabled mmWave bands—double-digit GHz bands that will enable literally billions more devices to share 5G networks, with billions more bits per second to each device.
Cameron:
In 2019, there will be realistic, tangible 5G activity. 2019 will be the year when we see the first commercial networks turning on and first handsets arriving in the market. Like
previous generations, 5G will have low initial penetration but will accelerate in coming years as technology matures and user devices emerge. Like 4G, it will take several years from initial launch until 5G is the dominant technology globally. Based on recent announcements from key industry players (i.e. Verizon, AT&T, Sprint and T-Mobile), first 5G commercial deployments will likely commence during the second half of 2019 with a target to have 5G commercial service available in 2020.
One question to consider is will these networks be “true 5G?” It will depend on how 5G is defined. An accepted definition of a 5G subscriber is a device supporting the NR protocol connected to an NR basestation. This is independent of which spectrum band the network utilizes. While some may consider 5G only as operating in mmwave spectrum, truly all spectrum is 5G spectrum and we will see NR deployed across the entire spectrum range, depending on what assets operators have available to support their strategy. If you recall the original IMT2020 KPIs set out by the ITU, there are several requirements which will certainly be met, such as spectral efficiency improvements and super-high user data rates. However, don’t expect all the KPIs to be achieved by any operator on Day 1. This is the reason why standards work is ongoing after Release 15. It will take time to evolve the network technology to meet all the original IMT2020 goals set out, such as ultra-high reliability and low latency.
The 5G standard timeline will continue to evolve. The initial Release 15 specification (non-stand-alone, NSA) was agreed upon and released at the end of 2017. There was a mid-year drop addressing standalone (SA) in June 2018, and we will continue to see a few late drops toward the end of 2018 into early 2019 mainly addressing dual connectivity. While there will be future enhancements, Release 15 laid down the foundation to enable initial SoCs to be defined and subsequent first user devices to be available in 2019. Work on Release 16 has started already with a target to complete by the end of 2019. Major elements of the next release improve the wireless industry’s ability to address vertical markets including enhancements to V2X, industrial IoT and URLLC. Also included are the exploration of 5G in unlicensed bands, 5G for nonterrestrial-use cases (satellite) and the move to higher frequency bands above 52.6 GHz. There will be work toward various enhancements to improve network efficiency, interference mitigation, MIMO enhancements and exploration to improve location and positioning.
For the sub 6-GHz infrastructure, Release 15 radio standards specifications are comprehensive, and we do not see the standards activity having material impact on the analog radio going forward. Most of the forward-looking features reside in the baseband, and generally will be implemented in software. This enables operators to install “5G-ready” equipment now, and evolve as new features become available. For mmwave, we are still early in the game and there may be some modifications to the standards as the industry learns and refines use cases. The Release 15 specifications are adequate to support first commercial deployments. However, the industry does not stand still, and 5G radios continue to evolve across all bands to deliver a lower cost of ownership to the operator.
There are hurdles that need to be cleared before full 5G deployment can be achieved. First, we need new spectrum. This is well underway globally whether it be mid-band or high-band spectrum, with many countries allocating spectrum for 5G. Ideal spectrum allocations for 5G are on the order of 50 MHz or more of contiguous spectrum to take full advantage of NR. Cost-effective 5G devices are required to drive subscriber adoption, whether these be user devices or machine-type devices. As with previous generations, we will see network infrastructure coverage roll out first, and then capacity later on as demand builds. In sub 6-GHz we will see the coverage layer built on massive MIMO using existing infrastructure followed by densification. Small cell deployments will be more critical to 5G to take advantage of higher frequency spectrum. Overall, whether an operator capacity layer relies on massive MIMO, mmwave or small cells, 5G will be built on a proliferation of antennae which in turn drives a proliferation of radios.
5G will also drive radio channel counts, whether it be for macro, massive MIMO, small cell or mmwave form factors. Macro base stations in the low bands will expand MIMO channel counts from 2T2R to 4T4R and possibly higher. Massive MIMO radios will have increased radio density per system ranging from 16T16R to 64T64R and mmwave radios will have up to 256 RF channels in the analog beamformers. The drive for smaller, more efficient radios we have seen in 4G continues and in fact accelerates as we move into this age of beamforming radios. As an industry, we need to continue to reduce size, weight and power (SWaP) consumption while supporting wider bandwidths and higher operating frequencies. There are various approaches to reduce the SWaP consumption of the radio systems, the most common approach leveraging circuit integration and Moore’s Law to shrink the size and improve power efficiency.
There will be exciting 5G applications coming in 2019. Initially 5G will provide the ability to deliver mobile broadband at lower cost to operators, but as full NR capability emerges, there are some exciting applications and use cases forthcoming. Industrial automation is one of the promising use cases that may leverage the low latency and high reliability provided by future 5G networks. There are a range of possible wireless use cases from predictive maintenance, to AR/VR for troubleshooting and repair, remotely controlled and cooperative robotics, to fully autonomous robotics. Initially, wireless networks need to provide similar connectivity to existing wired industrial Ethernet networks, but going forward, 5G may be leveraged to allow factories to create more flexible and efficient production lines.
Autonomous vehicles are quickly evolving with onboard sensor technologies and computing power gaining the ability to replicate the human driver. However, many agree that for Level 5 autonomy, reliable, ultra-low latency, wide-area connectivity will be required. The wide area connectivity will complement the power of the onboard sensors and decision making by providing situational awareness and extend the vehicle’s ability to look down the road to make decisions in a fraction of a second. Going forward, the evolution of 5G based C-V2X enables vehicles to share their sensor data across a wide area so that vehicles may better predict road conditions to plan their routes and take evasive action to avoid unsafe situations. EE
