Carrier aggregation development, which has been accelerating in the last year, led to products that were all the rage at the Mobile World Congress 2014 in Barcelona. Each promises giant leaps in data throughput.
Huawei’s demonstration of LTE-Advanced FDD+TDD convergence carrier aggregation across FDD and TDD LTE modes and Vodafone’s involvement are particularly interesting, according to Steven Hartley, principal analyst at Ovum.
“The benefit of CA across FDD and TDD LTE is that operators can combine cheaper TDD spectrum with more traditional FDD spectrum to boost capacity and downlink speeds,” Hartley said.
The demonstration, involving three FDD carriers and one TDD carrier, produced a single user peak downlink speed of an eye-popping 500 Mbps.
“In this case where partners are promising more than 500 Mbps, the cost efficiencies for an operator of leveraging the full range of spectrum assets available is unquestionable, but most operators have so far shied away from the technical complexities involved,” Hartley said.
Using Huawei’s technology, Vodafone combined 50 megahertz of FDD spectrum in the 800-MHz, 1800-MHz and 2600-MHz bands with its 20 megahertz of TDD spectrum in the 2600-MHz band in Spain.
Carrier aggregation speeds contrast glaringly with Vodafone’s 1800-MHz and 2600-MHz commercial LTE services, which were rolled out at the beginning of 2013 with a peak speed of 150 Mbps/user.
SK Telecom Demo Combines Three Channels
SK Telecom demonstrated LTE-Advanced by aggregating three bands at the Mobile World Congress. The carrier aggregation technology demonstration combined three 20-megahertz channels to offer speeds of up to 450 Mbps.
The Barcelona demonstration was only the latest in a rapid-fire string of new LTE-Advanced features from SK Telecom since last June. On Jan. 20, the carrier unveiled a wireless system that aggregates a 20-megahertz band and two 10-megahertz bands, supporting speeds of up to 300 Mbps. In November 2013, SK Telecom achieved throughput of 225 Mbps by aggregating a bandwidth of 20 megahertz in the 1.8-GHz band and a 10-megahertz channel at 800 MHz. In August 2013, the carrier combined a 20-megahertz downlink and a 15-megahertz uplink in the 1.8-GHz band; and in June, it combined a 10-megahertz channel in the 1.8-GHz band and a 10-megahertz channel in the 800-MHz band.
CA in Finland
Broadcom, Finnish carrier Elisa, and Nokia Solutions and Networks have demonstrated LTE-Advanced carrier aggregation on a live commercial network. The test aggregated two 20-megahertz channels in the 1800-MHz band and the 2600-MHz band to reach speeds of 300 Mbps.
Ted Abrams, Abrams Wireless, said that carrier aggregation is a milestone in spectral efficiency. But because it is only included in the latest version, Release 10, of the LTE-Advanced standard, it will take time to be rolled out to all U.S. networks.
“This gives all operators, large and small, the opportunity to harvest spectrum from various bands and carry broadband traffic through the air with an aggregated, composite carrier. Most of the LTE equipment deployed in the U.S.A. is Release 9, so it will be a while before all networks incorporate the carrier aggregation features of LTE-A,” he wrote.
ABI Research has ranked infrastructure vendors according to their perceived levels of innovation and implementation in small cells and carrier Wi-Fi. Alcatel-Lucent ranked highest, with an almost perfect score in both innovation and implementation. Huawei was not far behind.
The research firm wrote that Alcatel-Lucent has the largest number of publicized small cells contracts with tier-1 wireless operators. Huawei, on the other hand, has the “highest global reach in terms of small cells with a significant presence in all regions.”
On the innovation scale, Huawei was outranked by NSN, NEC and Cisco, but all had fewer implementations than Huawei. Of these three, Cisco came closest to Huawei and Alcatel-Lucent in terms of implementations.
–Ernest Worthman, Executive Editor, Small Cells magazine
All the buzz right now is 4G LTE build outs, but in one laboratory the 5G future is being forged.
Samsung Electronics announced that it has developed an first adaptive array transceiver technology operating in the millimeter-wave Ka bands for cellular communications and will provide data transmission speeds of up to several tens of Gbps per base station.
The millimeter-wave spectrum provides wide bands, which are good for high speed data, but the RF propagation makes for very short hops, at least that was true in the past. Samsung out to defeat theses propagation limitations by implementing adaptive array transceiver technology to achieve speeds of more than a gigabit over distances of up to 2 kilometers in the 28 GHz band.
Ted Abrams, consultant, AWI, told AGL Bulletin, “A 1.06 Gbps data highway across 2 kilometers of free space is something to be proud of, and Ethernet traffic will profitably flow at 28 GHz and beyond to the benefit of transport providers as well as consumers.”
The adaptive array transceiver uses 64 antenna elements to overcome the radio propagation loss at millimeter-wave bands, much higher than the conventional frequency bands ranging from several hundred MHz to several GHz. Commercialization of the technologies is expected by 2020.
“Innovative and commercially viable, adaptive array applications such as this latest Samsung development continue to increase bandwidth across wireless links,” Abrams said.
Samsung is not along in the 5G wireless quest. China established a government-led “IMT-2020 (5G) Promotion Group” for 5G research in February 2012, while the European Commission also plans to invest 50 million Euros in 2013 to bring 5G services to the market by 2020.
Abrams was already looking forward with anticipation to the next development at the vendor. “When Samsung next raises the bar to bi-directional throughput of 3-5 Gbps, then that ultra-fast wireless link could be converted away from Ethernet to native CPRI – Wow!”
More Work to Do on LTE-A…
A network trial in a crowded Japanese city has demonstrated that LTE-A technology can support speeds of 770 Mbps in the 3.5 GHz band, making use of Carrier Aggregation, Coordinated Multi-Point and Cloud baseband.
The demonstration was held in late August and was hosted by the Global TD-LTE Initiative . Issues discussed at the seminar included speeding up the release of 3.5GHz spectrum and adopting the same technologies to share the same ecosystem.
Japanese mobile operator and Sprint investor SoftBank held the demonstration in Tokyo’s densely urban Ginza district in cooperation with China Mobile, UK Broadband, representatives from the WiMAX Forum, as well as chipset companies.
A pre-commercial network-level performance evaluation conducted during the demo determined the network could provide a top user experience in Tokyo’s densely populated Ginza district. It was during this evaluation that advanced LTE-A technologies for the 3.5GHz band were demonstrated. The LTE-A technologies demonstration showed Huawei’s equipment can provide a max 770 Mb/s download speed and an average 500 Mb/s download speed over multiple network sites.
SoftBank also demonstrated a “five-carrier CA” technology for LTE TDD on the 3.5GHz band using a prototype system that can provide a max 1.2 Gb/s download speed when run on Huawei’s Ultra-wideband RRU (Remote Radio Unit). When deployed, a combination of Ultra-wideband RRUs can support more than 100 MHz instantaneous bandwidth and can be customized on-demand to accommodate new spectrum as it becomes available.
A flurry of multi-mode, multi-band small cells and chipsets are entering the market, as carriers begin to focus on improving 3G/4G LTE network performance through data offloading, while charting a smooth migration path from 3G to 4G LTE.
“Carriers worldwide are going to demand more small cells, to have absolute control over performance variables and to reduce their costs,” Ted Abrams, wireless consultant, AWI, told the DAS Bulletin.
Purewave launched a multi-mode, multi-band small cell base station this month, intend to providing simultaneous LTE, WCDMA and Wi-Fi coverage or a combination of these technologies chosen by the operator. The Lyra 400 supports up to 128 active users.
“There is a need for multi-mode technology because operators are not likely to invest in a single technology platform for any of their networks,” said Principal Analyst for Informa Telecoms and Media Malik Kamal-Saadi. “The equipment needs to be as future-proof as possible. From the device side, there are several flavors out there. Small cells must be able to support all of these devices, as well. Networks are multi-mode and multi-band, so small cells need to be also.”
Huawei recently jointly won an award for “Best Innovation in Commercial Deployment” with Vodafone Group at the 2013 Small Cell World Summit in London. The award cited a project for a “MetroZone Small Cell Solution [that] enables ‘Smart Cities’ today and in the future.” The deployment used Huawei’s AtomCell, which is a multi-mode (GSM/UMTS/LTE/WiFi) base station with a power level of 10 watts or less. AtomCell Pico and WiFi access points (AP) offload 60 percent of all indoor traffic, according to the company’s web site.
Last fall, Ubiquisys (now owned by CISCO) launched a multi-mode indoor metrocell, the GM7, which runs 4G LTE and 3G HSPA+ simultaneously, as well as Wi-Fi. Software-deﬁned resource allocation allows the operator to tune the balance of 3G and 4G capacity according to changing demand. The GM7 can, therefore, be deployed and remotely upgraded to be 3G-only, 4G-only, or a combination of 3G and 4G.
Ericsson’s multi-mode radio base station, the RBS 6000. supports GSM/ EDGE, WCDMA/HSPA, LTE and CDMA in a single unit. Alcatel-Lucent’s small cells have similar features.
Broadcom introduced multimode, 3G/4G small cell technology in February, using what it called the “industry’s first” dual-mode WCDMA and LTE small cell systems on a chip. On a 20-megahertz channel, the BCM617xx Series supports 4G LTE with full 150 Mbps down link and 50 Mbps uplink and 128 active users, and 32 active 3G WCDMA users with data rates of 42 Mbps in the downlink and 11 Mbps in the uplink. It also supports 4G LTE on a 40 megahertz channel and 256 active users, or 64 active 3G WCDMA users with data rates of 84 Mbps in the downlink and 22 uplink Mbps.
Greg Fischer, Broadcom’s vice president and general manager for broadband carrier access, said, “As mobile operators continue to focus on delivering faster data rates and better quality of service, Broadcom’s dual-mode devices support a seamless transition from 3G to 4G LTE for providers and the consistent, high-performance mobile experience end-users crave.”
Ubiquisys’ GM7 uses Texas Instruments’ TMS320TCI6614 chipset solution and ActiveCell software, which can dynamically balance between 3G and 4G according to demand.
In June, Qualcomm Technologies introduced a family of small cell chipsets, the FSM99xx, which integrates the company’s 3G and 4G technologies and supports advanced 802.11ac/n Wi-Fi in pico, metro and enterprise small cells.
While chipset OEMs are coming up with reference architecture for multi-technology small cells (WCDMA, LTE and Wi-Fi), no one has produced a chipset with both 3GPP technologies (GSM,WCDMA,LTE) and 3GPP2 technologies (CDMA, 1XRTT, EVDO), which is necessary for a neutral host small cell, Manoj Das, director, technology services, Mantra Telecom, told DAS Bulletin.
“Multi-mode, multi-band, multi-technology, multi-protocol small cells would be required for neutral host small cell network,” he said. “That is a far reality at this point of time.”
Multi-band chipsets are here now. But radios, filters and antennas are band specific, according to Abrams.
“Solutions that claim multiple frequency bands need to recalibrate filters and exchange antennas in real time, he said. “The idea is feasible, but not commercial right now.”
ABI Research has ranked Nokia Siemens Networks at the top in its macro base station vendor competitive assessment for its performance in innovation and implementation. But Ericsson, Alcatel-Lucent and Huawei were not far behind.
“The macro base station market is hyper competitive and we noticed a high level of innovation from all vendors, coupled with real and significant achievements as the vendors equip and modernize the world’s mobile networks as they continue to build out for coverage and transition to the latest 4G protocols and distributed architectures,” said Nick Marshall, principal analyst at ABI Research.
The subjective assessment by ABI graded the major base station manufacturers in terms of criteria under two major categories: innovation and implementation. Criteria determining innovation included R&D investment, essential intellectual property, advanced feature road map, small cell/hetnet development, and multi-protocol support. Under the category of implementation ABI looked at market share, geographical penetration, financial and organizational health, LTE RAN contracts, major customer wins and vendor portfolio.
In particular, NSN gained best-in-class scores in the essential IP, advanced features road map, and multi-protocol support categories and LTE RAN contracts.
In terms of innovation, NSN’s Smart Scheduler, which is responsible for efficient interference mitigation and QoS assurance, drew the attention of ABI. Technologies like the Smart Scheduler will give systems the ability to handle voice over LTE traffic.
“The Smart Scheduler uses fast-frequency selective (uplink and downlink) distributed scheduling for guaranteed bit rate and latency with minimum fading and maximum uplink interference mitigation,” Marshall said. “The Smart Scheduler capability enables superior network quality and a significant reduction in costs by enabling a higher number of simultaneous subscribers in a given site.”
Both Ericsson and NSN are providing base station infrastructure for T-Mobile’s LTE Advanced ready system deployment, which has been getting a lot of press for potentially being able to deliver 150 Mpbs over a 40-megahertz swath of spectrum. To get the speed and maintain the signal-to-noise ratio, the specifications for LTE-Advanced call for advanced antenna technology, while the base station must have the computing power to handle the data.
“[T-Mobile’s network] is going to be super-fast, because it bought the latest [LTE-Advanced-ready] gear from NSN with two-by-two MIMO and four-by-four MIMO [antennas]. It’s helping them achieve some pretty good performance figures,” Marshall said.
Ericsson, Alcatel-Lucent Also Receive Accolades
NSN had company in ABI Research’s competitive assessment, which ranked Alcatel-Lucent as the most innovative vendor with three best–in-class scores for innovation in the areas of R&D investment and commitment, small cell and hetnet development and TCO innovation. Ericsson achieved first in the implementation category with the most LTE contracts and subscriber potential among the vendors from networks equipped by Ericsson. Huawei also ranked among the leaders.
Samsung is the rising star in base stations, according Marshall, with increasing market share and a growing number of LTE contracts with carriers, such as Sprint and MetroPCS and several in the U.K. and Ireland. Additionally, Samsung has entered the small cell arena with contracts with Sprint and KDDI in Japan.
“Samsung has a huge R&D staff. They can pull on all sorts of resources to do this,” Marshall said. “I can see them moving into position as a base station power some day.”