by Caroline Gabriel, Research Director
There are some '5G' discussions and claims which are completely legitimate to have in 2015, especially if next generation networks really are to start appearing from 2020. Vendors, operators and research institutes need to identify the areas in which R&D dollars will be best spent, and it is vital for regulators and policy makers that there are some clear directions on how spectrum will be used in future networks.
There are others which are dramatically premature, particularly all the talk of the '5G air interface' in Barcelona at the recent Mobile World Congress, probably the aspect on which fewest parties are in agreement, and which really does have to wait for the 3GPP to kick off activities.
There are interesting projects in this area - for instance, Alcatel-Lucent and Intel are working on the Universal Filtered OFDM air interface, which had its origins in WiMAX, and could be one candidate for the next generation.
Separate air interfaces may be needed to support IoT nodes in lower frequency bands and high bandwidth applications in the 10-100GHz range. Since the official spectrum policies above 6GHz may not be decided until WRC-19, the industry faces the interesting challenge of "designing new air interfaces ahead of when spectrum is released", as Intel put it.
But there is not even consensus on whether a new air interface is needed at all. "I suspect that it will require a new air interface," said Alex Jinsung Choi, head of SK Telecom's corporate R&D center in South Korea, and Eduardo Esteves, VP of product management for Qualcomm, echoed this as both took part in a panel discussion at Mobile World Congress. But Tom Keathley, SVP of wireless network architecture and design at AT&T, told the same session: "I don't think we know at this stage whether a new air interface will be required. I think it will be a bit of time before we can answer that with certainty."
In general, despite all the marketing hype attached to so-called pre-5G demonstrations, Barcelona attendees were firmly focused on the short to medium term and the achievable. But that did not stop a large number of organizations using the event to launch their 5G manifestos, and seek to place themselves and their particular agendas in the driving seat.
Just ahead of the show, the European Commission fronted a paper which set out an inaugural 5G vision based around its previously announced '5G Public Private Partnership' (5GPPP). It stated the issues (the easy bit) and recited the usual mantras - data volumes of 10 terabytes per square kilometer; one million terminals per square kilometer; one-tenth of the energy consumption and one-fifth of the latency of current platforms; cutting network management to 20% of today's costs; data rates of 50Mbps to every user; location services to within a meter. Then it gave itself the familiar, but perhaps unachievable, deadline of five years to solve all that.
The EC received a lot of attention, but there were plenty of other alliances and proposals. Here is Rethink's selection of the ones which are likely to have a real impact on how '5G' pans out:
The IPv6 Forum has launched a new 5G World Alliance, with the lofty aim of achieving "seamless global network interoperability". President Latif Ladid said: "We are talking here about a 5G world where technologies such as an all-IPv6-based M2M, the mobile IoT, mobile cloud computing, SDN, NFV, fringe and tactile internet will converge over fixed and mobile networks to change lives and businesses everywhere." Ladid said the alliance was currently establishing board members and said it would work alongside the ETSI IPv6 ISG to share its findings.
Among the objectives that the 5GWA is looking to achieve are:
- Global harmonization and synergies of the telecom and internet worlds
- The creation of large-scale worldwide interoperable testbeds
- Promotion of end-user empowering applications and global solutions
- Promotion of interoperable implementation of converging and integrated standards
- Developing educational and '5G-ready' programs
- Resolving issues that could create barriers to 5G deployment
4G Americas has signed a memorandum of understanding with the 5GPPP, outlining the basis for cooperation and collaboration between the two organizations. The MoU specifically agrees to share information on basic system concepts for 5G frequencies to support the global regulatory process, and preparation of future global 5G standards by identification of common interest and consensus building.
The NGMN (Next Generation Mobile Networks) Alliance has published a white paper detailing end-to-end operator requirements for 5G, intended to guide the development of future technology platforms and standards. A global team of more than 100 experts contributed to the white paper by developing the consolidated operator requirements. These are summarized predictably enough - "the capabilities of the network need to be expanded to support much greater throughput, lower latency and higher connection density. To cope with a wide range of use cases and business models, 5G has to provide a high degree of flexibility and scalability by design. In addition, it should show foundational shifts in cost and energy efficiency. On the end user side, a key requirement for 5G will be that a consistent customer experience is achieved across time and service footprint. NGMN envisages a 5G ecosystem that is truly global, free of fragmentation and open for innovations."
Ericsson announced its new '5G for Sweden' research program, involving companies such as Scania and Volvo, as well as several academic and research partners from across the country.
Ericsson said it wanted to develop and roll in ICT solutions into products and services built upon emerging 5G standards. An example of this is work it is doing with Scania, which will examine future transport solutions.
Nokia and Ericsson will collaborate with Korea Telecom on 5G and IoT following the signing of new memorandums of understanding. The first sets up an IoT and LTE-M lab to develop business models aimed at convergence and the automotive industry. This will be on KT premises and will involve all three Nokia business units (Networks, Here and Labs). The second builds on an existing 5G cooperation with Ericsson.
Nokia and NTT Docomo carried out a joint demonstration in Barcelona, of technologies they say will be part of the '5G' networks the pair plan to showcase at the 2020 Olympic Games in Tokyo. They achieved above 2Gbps in the 70GHz band.
China Mobile, NTT Docomo and KT announced that they would conduct a three-way 5G technical collaboration in an attempt to accelerate commercial deployments and drive standardization efforts. They will explore new services and vertical markets enabled by 5G, jointly identify 5G key technologies and prove the validity of system concepts. The operators will also work with global organizations such as ITU, 3GPP, GSMA, NGMN and GTI to facilitate global harmonized spectrum planning and a unified global 5G standard, the companies said in a joint statement.
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by Caroline Gabriel, Research Director
So Mobile World Congress (MWC) is over for another year, amid the usual record-breaking statistics (from 93,000 visitors, up 45% on the first Barcelona event in 2006; to 7.55Gbps wireless transmission speeds demonstrated by SK Telecom and Samsung).
There were plenty of eye-catching devices, with the Galaxy S6 Edge undoubtedly the star of the show in terms of headline power, though otherwise the mobile gadget space is fragmenting rapidly. The days of a line-up of remarkably similar large-screened smartphones are over - those handsets are there, at ever cheaper price points, but they jostle for attention with virtual reality headsets, connected clothing, smart coffee makers and whisky bottles, and of course the connected cars (Fiat 500 seemed to be the most popular model on display). Indeed, wearables and associated IoT (internet of things) apps virtually colonized MWC's second venue (its previous home in the Fira complex at Plaza Espanya).
Other headlines were sparked by the companies which, back in 2006, when the 3GSM show relocated from Cannes and changed its name, scarcely figured. Google's MVNO plans, Facebook's extension of its internet.org initiative, PayPal's endorsement of NFC with its acquisition of Paydiant - these were the talking points, drowning out the traditional keynote addresses by the major mobile operators.
Traditionally, the CEOs of the established cellcos have used their conference platforms to lay down their demands to the industry (remember then-CEO of Vodafone, Arun Sarin, warning the LTE sector in 2007 to speed up its efforts or face the WiMAX threat; or trading insults with his Nokia counterpart over 3G delays in 2004). These days, it is the new breed of service providers which are setting the pace - Google's Sundar Pichai may have announced a fairly cautious MVNO plan, but his speech had far wider implications, including the call for full WiFi/cellular convergence, still a divisive theme at an event dominated by the entrenched interests of 3GPP platforms.
Those interests are particularly threatened in the IoT, which was a huge theme of the show this year. As the news that Freescale and NXP are to merge neatly demonstrated, this is a dangerous world for the traditional wireless operators and vendors. It throws up significant opportunities to extend their businesses into new, high growth markets, bringing companies like Freescale and NXP - which had been squeezed badly in the smartphone segment - back to Barcelona with new connected device platforms. But the margins on those chips are low and the IoT is already sparking consolidation, as this semiconductor mega-merger illustrates, with the old-school suppliers and operators needing to huddle together for warmth in a business of scale.
Of course, the carrier's network - wireless RAN, core and transport, and increasingly virtualized versions of those - remains the heart of the serious conversations and trading at MWC. With that in mind, we selected our key themes of 2015:
The shape of the new cell site:
After several years when the ever-shrinking base station was the central theme in RAN discussions, this year saw most of the major equipment vendors announcing major refreshes of their macro layers. Massive MIMO (or at least, 8x8 arrays), carrier aggregation across three bands and including TDD, Coordinated Multipoint and Cloud-RAN - these were the important features of the new macro. This was not 5G, but technologies that will be deployable this year or in 2016 - indeed, it seems more than likely that, however '5G' turns out, it will be focused on the dense capacity layer, while the macro coverage umbrella will remain 4G for decades to come.
Small cells were out in force too, and in a widening variety of form factors. Traditional homogeneous mini-base stations are part of a very variegated approach to the capacity layer. They may form clusters with their own controller (local or virtualized) to support an enterprise or a rural deployment. For the former, the big news was that Cisco will resell the Spidercloud Enterprise-RAN solution, despite its own 2013 acquisition of small cell pioneer Ubiquisys. For the latter, the Small Cell Forum kicked off its latest Release Program, devoted to easing deployment issues in rural and remote scenarios, from villages to oil rigs to temporary situations such as disaster relief. Quortus, with its virtualized packet core, was one of the first to update its portfolio to target this important area, while Parallel Wireless was showing off its rural solution, implemented by EE in the UK.
The classic small cell is expanding its reach, seeking to provide greater value than basic coverage and capacity. Ip.access, another of the founders of this industry, has gone as far as to position its Presence Cell purely as the enabler of big data and e-commerce services - and not necessarily connected to the main network at all. Its approach has convinced Vodafone, which announced that it would deploy the retail-oriented platform.
Then there were small cells which did not follow the traditional architecture. Stripped-down antenna/radio units for Centralized-RAN; separate antennas optimized to work with urban small base stations, from companies like Kathrein and CommScope; a converged WiFi/cellular unit from Alcatel-Lucent; hosts of carrier WiFi access points and management platforms as well as lower-power DAS solutions. This is a segment where all options are open, and in which operators will pick and choose the solutions which suit their individual spectrum, business model and capacity requirements.
The virtualization of the RAN is a more distant prospect, for most operators, than the lower risk decision to run a packet core or even a CPE as software on off-the-shelf hardware. However, some pioneers were demonstrating their vRANs, notably Telefonica and China Mobile, and Intel was locked in combat with the ARM ecosystem over the market for high performance processors, optimized for C-RAN servers and accelerators, as the industry chases a general purpose chip with the horsepower to run high end network processes as well as customized silicon.
Not everything can be converted to software of course, though even the physical elements like antennas and radios will be increasingly software-defined and programmable. Pushing that trend to its extreme was Cambridge Consultants, which has developed the IP for the first all-digital radio transmitter, Pizzicato. Unlike conventional software defined radio, it has no analog components, which allows many radios to work together without interference. In the first trial, Cambridge Consultants created 14 simultaneous cellular base station signals at low power, and with the radios "squashed together in a way that analog doesn't tolerate". Such solutions can be programmed to generate manhy combinations of signals at any frequency in an adaptive way. The Pizzicato transmitter consists of an integrated circuit outputting a single stream of bits, and an antenna.
Of course 5G was a massive talking point, though outside the conference halls and the big vendors' glossy demonstrations, there was less hype than expected about the next generation of wireless, with most operators more focused on technology they could deploy in the next 1-2 years, and eager to wait for key decisions at the World Radio Conference in November, and at the 3GPP and other standards bodies, before getting too excited about 5G. Many alliances were formed and roadmaps laid down, but the most tangible aspect of the discussion was the use of millimeter wave spectrum, in which there were many demonstrations for access and backhaul. The high frequency bands are almost certain to play a key role in next generation wireless, and like many supposed elements of 5G, they will start to have a real impact far earlier, as seen in technologies like 60GHz WiGig and some small cell backhaul solutions, notably InterDigital's Peraso baseband system-on-chip for this market.
There was considerable excitement about LTE-LAA (Licensed Assisted Access), which uses 5GHz spectrum for supplemental downlink to a licensed-band 4G network. Although it will not be standardized until next year, supporters like T-Mobile and Qualcomm showed off their plans, along with a companion technology which aggregates a 5GHz WiFi carrier to LTE. Cellular players were trying to dampen down talk of colonizing licence-exempt spectrum, and stressing that LTE and WiFi could coexist peacefully, both in technical terms and in carriers' business models. However, while LAA is clearly a small cell play, given the high frequencies and low power limits involved, some were arguing that the industry would do better to focus on getting 3.5GHz standardized as a specific small cell band, avoiding WiFi showdowns and the quality challenges of unlicensed spectrum.
As noted above, the IoT was an important theme, but given the nature of the event, there was a particular focus on LTE solutions to support IoT applications, and the question of whether these will prove viable as alternatives to WiFi or specialized long range networks such as Sigfox or LoRa. Huawei was demonstrating its contributions to future LTE-M standards, while the LTE-only baseband specialists, such as Sequans and Altair, have a major opportunity to push 4G-only solutions into a mass market. While the 3GPP works on LTE Category 0 as the underpinning of LTE-M, for now the vendors have resurrected Cat-1, whose low data rates made it a Cinderella specification in the broadband world, but whose ultra-low power consumption now makes it a candidate for the cellular IoT. Sequans, Ericsson and Verizon announced that they had run tests on a commercial LTE network, delivering 10Mbps data rates at very low cost and power, and with peaceful coexistence with higher-powered LTE devices.
The new operators:
Facebook and Google both tried to paint pictures in which they had ongoing close alliances with cellular operators, but they managed to visualize a world in which the MNO's role was severely constrained. They are driving new approaches to the network - full WiFi/cellular convergence; harnessing of LTE-Broadcast for social media as well as content; dynamic spectrum allocation on-demand to hundreds of providers; low cost delivery to the 'next billion' world inhabitants. All of these examples see the web giants becoming less over-the-top and actually shaping the network of the future, with the cellcos just providing part of the plumbing, however important that part. The vision will be supported by virtualization and the ability for cloud platforms to support a new generation of network as a service concepts, spanning WiFi, LTE and other connections, and eventually assigning capacity dynamically to large numbers of MVNOs. That is the end game for platforms like XCellAir, which has been spun out of InterDigital. Such services could be run by traditional operators, as AT&T's Domain 2.0 roadmap clearly envisages, but they could equally be controlled by web or IT majors.
The new operating systems:
It isn't all going Google's way though. Android dominated a show in which Apple plays not part (except in everyone's conversations), but the search giant is struggling to control and unify the user experience as large device and service providers create their own user interfaces and developer platforms. Amazon AppStore broke the 400,000 apps mark, for instance, boasting of "huge progress" with its alternative to Google Play. And as smartphones morph into many new types of connected device, many of them driven from the cloud, there may be the chance for different operating systems to break the Android/iOS duopoly. There was considerable interest in the mobile implementations of Windows 10 from Microsoft, while start-up options like Jolla's Sailfish and Mozilla's Firefox Mobile were looking, for the first time, like credible platforms with operator support, not just bright open source ideas.
by Caroline Gabriel, Research Director Maravedis-Rethink
Big wireless suppliers try to influence operators' and regulators' agendas as they dream up visions of the next generation.
While the big network vendors have mainly confined their MWC announcements and previews to relatively short term developments, none of them could resist breathing the '5G' word, seeking to convince their audiences that they had somehow stumbled on the secret ingredients for the next generation of wireless, well ahead of the actual standards bodies.
Ericsson promised to demonstrate "fundamental 5G functionality" in Barcelona, to support both human and machine applications. The Swedish vendor even unveiled results from its 5G testbed, which it says has performed the remarkable feat of already achieving two 5G milestones (even before anyone knows what 5G will be). The testbed includes base stations and concept devices operating in the 15GHz band, indicating the importance most vendors are placing on high frequency spectrum for next generation standards.
Of course, like all the vendors, Ericsson hopes that by calling its R&D efforts '5G' it will improve their chances of being included in the standards, or at least the basic concepts, which do go on to underpin the next generation.
Its two supposed milestones are 5G/LTE dual connectivity and 5G multipoint connectivity, the company said. The first supports a 5G device moving between LTE and the new network, establishing simultaneous connections with both before seamlessly handing over, in order to smooth the user experience. The second allows the 5G device to connect to two 5G base stations simultaneously, improving bit rate performance with multiple downlink streams, as well as signal strength and resilience.
Both of these are 4G concepts, adapted for the supposed characteristics of the new generation network (ultra-small cells, ultra-low power, support for millions of sensors, and so on). As in 4G, multipoint connectivity will be particularly important to enable multilayer HetNets with macrocells, small cells and WiFi interworking seamlessly.
Nokia, too, has been giving a glimpse of what 'future 5G' demonstrations it will make in Barcelona. It will show off radios running in high frequency millimeter and centimeter wave bands (3.5GHz to 70GHz), which will boost capacity, and will be combined with new frame structures to support latency down to single-digit milliseconds. These will be particularly focused on the IoT.
Its good customer Korea Telecom will be partnering with Nokia in the MWC 5G and IoT demonstrations and the operator's head of networks, Seong-Mok Oh, said: "I hope that the strategic partnership with Nokia, including the joint demonstration at MWC 2015, will lay a foundation for the two companies' leadership position along the journey towards an IoT world."
Nokia has also been working on massive MIMO trials with KT's rival, SK Telecom, though these are looking to a shorter timeframe than 5G, initially at least. The two companies said this week they had achieved peak downlink speeds of 600Mbps using 4x4 MIMO. They first got to 300Mbps by implementing the MIMO array in a 20MHz block of spectrum, and then doubled that speed by doing the same in a second 20MHz chunk and aggregating the two. Devices with four antennas and carrier aggregation support have not been developed, so Nokia used a simulated device supplied by test and measurement specialist Aeroflex.
And 4×4 MIMO will be challenging to deploy in a commercial network, because of the need to squeeze four antennas into a small device, and also because it is difficult to maintain the right RF conditions for the 4x4 airlink, so real world user experience may be patchy.
Japan's NEC promises to outline its 5G vision with demonstrations and three white papers outlining what it believes will be the key enabling technologies in 2020 and beyond. These focus on the access network, the backhaul, and massive MIMO, particularly its development of a 'massive-element antenna' for future small cells.
Like Huawei, its post-2020 vision is heavily geared to machine services, from intelligent transport to the use of big data to save energy consumption, as well as next generation consumer multimedia offerings and ultra-accurate logistics systems. The heart of this platform will be SDN, virtualization and Cloud-RAN, all areas where NEC has engaged in advanced R&D and trials.
And Samsung says it will show off three 5G "technology candidates" at MWC. Chang Yeong Kim, head of the DMC R&D Center at the Korean firm, said in a statement: "We consider 5G to be a transformation of how networks are constructed and how radio resources are used. To support 100 times greater throughputs at a fraction of the latency, we need to consider more than just a single network component; we need to look at how everything works together."
The three candidates highlighted by Samsung are a nearly-commercial implementation of wireless backhaul in 60GHz spectrum, combining active and passive radio steering techniques to increase the range of the radio without exceeding unlicensed-band power output limits. An active antenna array enables a beamformed radio signal to be directed at a passive lens antenna, which further concentrates the radio signal toward a fixed point with high precision and multi-gigabit data rates.
The second technology is 'full dimension MIMO' (FD-MIMO). Current MIMO solutions have antennas configured to form beams only horizontally. Users who are at the same horizontal angle from the antenna (even at different vertical angles) still receive the same signal and continue to share radio resources. With the introduction of FD-MIMO and 2D-array antenna technology, wireless signals can be adaptively beamformed to specific users in both horizontal and vertical domains. That delivers a more targeted signal to more than eight users per cell at a time and is good for high rise buildings, stadiums and other crowded locations.
Samsung said it is leading the standardization of FD-MIMO in the upcoming 3GPP Release 13.
It also says it will demonstrate peak stationary data rates of 7.5Gbps - or 1.2Gbps when moving at 100 kilometers per hour - using 28GHz millimeter wave spectrum and Samsung's Hybrid Adaptive Array antenna technology.
However, amid all this cleverness, Peter Merz, head of radio systems technology and innovation at Nokia Networks, injected a note of realism in a recent interview with Telecom.com. He said: "I want to stress that 5G is not around the corner. We're expecting the first commercial roll-outs and deployments starting in 2020. We still have five years to go in order to research technologies, go through standardization, free up spectrum, verify the technologies and then iron out specifications in order to have a ready-made, lean-cut, efficient technology that can be deployed by operators starting in 2020. 5G is like a marathon, it's not a race."
We can only hope that vendors are bearing such words in mind in Barcelona and focusing most of their efforts on real world requirements for 2016 to 2018, even while they seek to influence operators, standards bodies and regulators building their long term plans.