PARIS—The emergence of the fifth-generation (5G) mobile network is currently the big challenge, and the deepest mystery, in the technology world.
As Will Strauss, president of Forward Concepts, told us last week, “In some ways 5G is like the Indian legend of the four blind men trying to determine what an elephant really is.”
Prior to the Mobile World Congress next week, we posed ten questions to some industry analysts and observers.
Among industry observers, we talked to David Hutton, director of technology at the GSM Association (GSMA) and James Kimery, director of RF Communications and Software Defined Radio (SDR) at National Instruments (NI).
GSMA is an association of mobile operators and related companies devoted to supporting the standard. GSMA’s mission is to guide the industry to focus on “use cases” and develop the new standard to benefit consumers and enterprises, explained Hutton. “5G development should not be driven solely by advancements of technology.”
NI, an automated test equipment and virtual instrumentation software company, is relatively new to the cellular community. It had very little to do with the making of 4G or any previous standards. But things have completely changed since 2010, according to Kimery.
The complexity associated with the development of 5G and its prototypes has made NI’s software-defined radio platform an indispensable tool for both academic researchers and the telecom equipment vendors involved in 5G innovation.
NI has now put itself in a unique position in the 5G community, as a keen observer of various trials and standards meetings. The company sees on-going developments first hand and from a neutral position.
1. What will the emerging 5G standard offer?
Its promised blessings, according to NI’s Kimery, are threefold — broadband data for smart devices, ultra-reliable/ultra-fast low-latency communication for automotive, and machine-type communication for massive numbers of connected devices.
Jim McGregor, founder and a principal analyst for TIRIAS Research, added, “Some significant key components to 5G are enhanced carrier aggregation; aggregation with Wi-Fi and unlicensed spectrum and IoT solutions.”
2. Will 5G be compatible with 4G?
“Not compatible,” said Kimery. “Technologies currently being discussed are a departure from 1G, 2G and 3G.”
However, David Hutton, director of technology at GSMA, provided more nuanced answers. “Because 5G is not one technology but rather an ‘ecosystem’ of standards, we see that 5G will maintain some backward compatibility with 4G.”
Kimery’s assumption is based on what the 3GPP (The 3rd Generation Partnership Project) agreed on about 5G last fall in Pheonix. At that time, the group agreed to ensure:
- Radios <6 GHz and >6 GHz
- A backward-compatible radio access technology (RAT) — LTE Evolution
- A non-backward-compatible RAT — 5G New RAT
Forward Concepts’ Strauss summed it up: “One thing obvious to me is that 5G (circa 2020) will be based on LTE as the base controlling logic as more and higher frequencies are added, more bonding of multiple frequencies (carrier aggregation) and greater antenna counts along with MIMO and directional broadcasts from the base station(s).”
3. We’ve seen many 5G trial announcements. When we don’t even have the 5G standard, what exactly are they trialing?
It turns out most of these trials are "pre-commercial trials" – focused on technology feasibility and reliability. The industry is increasingly interested in using the millimeter-wave spectrum above 6GHz for 5G. “This is a big jump for everyone in the cellular industry,” said Kimery. “So far, the mobile industry has only used spectrums below 6GHz.”
Enabling mmWave cellular systems, however, comes with its own challenges. They include the requirements for solving the channel impairments and propagation characteristics of high-frequency bands.
Many carriers and network equipment vendors are testing performance of their own proposed systems and collecting the results, said Kimery.