Showing posts with label LTE-A. Show all posts
Showing posts with label LTE-A. Show all posts

Sunday, March 16, 2014

Video Tutorial: Synchronization and Timing for LTE-Advanced

 Martin Nuss, CTO of Vitesse Semiconductor, provides an overview of Synchronization and Timing for LTE-Advanced
http://youtu.be/PikErOZ8xyg

Part 2 - What are the key differences between LTE FDD and TDD, and LTE-Advanced?
http://youtu.be/dqZC6bx-iHo

Part 3 - Do operators need to run their backhaul networks differently for LTE FCC, TDD and LTE-Advanced?
http://youtu.be/Aw9fkJEkFdM

Part 4 - Why are mobile operators looking for GPS alternatives?
http://youtu.be/G-_erWLBnZk

Part 5 - What standards are being developed to deliver time and phase synchronization with IEEE 1588?
http://youtu.be/gseBV35gV54

Part 6 - What impact will the new ITU-T standard for time and phase delivery have on network architecture?
http://youtu.be/2r62spb4TFU

Part 7 - What impact will the new ITU-T standard have on network operators and telecom equipment suppliers?
http://youtu.be/JVco_hRw7AE

Part 8 - What are Vitesse's solutions for OEMs to achieve the new ITU G.8273?
http://youtu.be/0gq5HxjzXhY



Wednesday, February 26, 2014

Blueprint: Impending ITU G.8273.2 to Simplify LTE Planning

By Martin Nuss, Vitesse Semiconductor

Fourth-generation wireless services based on long-term evolution (LTE) have new timing and synchronization requirements that will drive new capabilities in the network elements underlying a call or data session. For certain types of LTE networks, there is a maximum time error limit between adjacent cellsites of no more than 500 nanoseconds.

To enable network operators to meet the time error requirement in a predictable fashion, the International Telecommunications Union is set to ratify the ITU-T G.8273.2 standard for stringent time error limits for network elements. By using equipment meeting this standard, network operator will be able to design networks that will predictably comply with the 500-nanosecond maximum time error between cellsites.

In this article, we look at the factors driving timing and synchronization requirements in LTE and LTE-Advanced networks and how the new G.8273.2 standard will help network operators in meeting those requirements.

Types of Synchronization

Telecom networks rely on two basic types of synchronization. These include:
Frequency synchronization
Time-of-day synchronization, which includes phase synchronization

Different types of LTE require different types of synchronization. Frequency division duplexed LTE (FDD-LTE), the technology that was used in some of the earliest LTE deployments and continues to be deployed today, uses paired spectrum. One spectrum band is used for upstream traffic and the other is used for downstream traffic. Frequency synchronization is important for this type of LTE, but time-of-day synchronization isn’t required.

Time-division duplexed LTE (TD-LTE) does not require paired spectrum, but instead separates upstream and downstream traffic by timeslot. This saves on spectrum licensing costs but also allows to more flexible allocate bandwidth flexibly between upstream and downstream direction, which could be valuable for video.  Time-of-day synchronization is critical for this type of LTE. Recently TD-LTE deployments have become more commonplace than they were initially and the technology is expected to be widely deployed.

LTE-Advanced (LTE-A) is an upgrade to either TD-LTE or FDD-LTE that delivers greater bandwidth. It works by pooling multiple frequency bands, and by enabling multiple base stations to simultaneously send data to a handset. Accordingly adjacent base stations or small cells have to be aligned with one another – a requirement that drives the need for time-of-day synchronization. A few carriers, such as SK Telecom, Optus, and Unitel, have already made LTE-A deployments and those numbers are expected to grow quickly moving forward.

Traditionally wireless networks have relied on global positioning system (GPS) equipment installed at cell towers to provide synchronization. GPS can provide both frequency synchronization and time-of-day synchronization. But that approach will be impractical as networks rely more and more heavily on femtocells and picocells to increase both network coverage (for example indoors) and capacity. These devices may not be mounted high enough to have a line of sight to GPS satellites – and even if they could, GPS capability would make these devices too costly.  There is also increasing concern about the susceptibility of GPS to jamming and spoofing, and countries outside of the US are reluctant to exclusively rely on the US-operated GPS satellite system for their timing needs.

IEEE 1588

A more cost-effective alternative to GPS is to deploy equipment meeting timing and synchronization standards created by the Institute of Electrical and Electronics Engineers (IEEE).

The IEEE 1588 standards define a synchronization protocol known as precision time protocol (PTP) that originally was created for the test and automation industry. IEEE 1588 uses sync packets that are time stamped by a master clock and which traverse the network until they get to an ordinary clock, which uses the time stamps to produce a physical clock signal.

The 2008 version of the 1588 standard, also known as 1588v2, defines how PTP can be used to support frequency and time-of-day synchronization. For frequency delivery this can be a unidirectional flow. For time-of-day synchronization, a two-way mechanism is required.

Equipment developers must look outside the 1588 standards for details of how synchronization should be implemented to meet the needs of specific industries. The ITU is responsible for creating those specifications for the telecom industry.

How the telecom industry should implement frequency synchronization is described in the ITU-T G.826x series of standards, which were ratified previously. The ITU-T G.8273.2 standard for time-of-day synchronization was developed later and is expected to be ratified next month (March 2014).
Included in ITU-T G.8273.2 are stringent requirements for time error. This is an important aspect of the standard because wireless networks can’t tolerate time error greater than 500 nanoseconds between adjacent cellsites.

ITU-T G.8273.2 specifies standards for two different classes of equipment. These include:
Class A- maximum time error of 50 ns
Class B- maximum time error of 20 ns

Both constant and dynamic time errors will contribute to the total time error of each network element, with both adding linearly after applying a 0.1Hz low-pass filter. Network operators that use equipment complying with the G.8273.2 standard for all of the elements underlying a network connection between two cell sites can simply add the maximum time error of all of the elements to determine if the connection will have an acceptable level of time error. Previously, network operators had no way of determining time error until after equipment was deployed in the network, and the operators need predictability in their network planning.

Conforming to the new standard will be especially important as network operators rely more heavily on heterogeneous networks, also known as HetNets, which rely on a mixture of fiber and microwave devices, including small cells and femtocells. Equipment underlying HetNets is likely to come from multiple vendors, complicating the process of devising a solution in the event that the path between adjacent cell sites has an unacceptable time error level.

What Network Operators Should Do Now

Some equipment manufacturers already have begun shipping equipment capable of supporting ITU-T G.8273.2, as G.8273.2-compliant components are already available. As network operators make equipment decisions for the HetNets they are just beginning to deploy, they should take care to look for G.8273.2-compliant products.

As for equipment already deployed in wireless networks, over 1 million base stations currently support 1588 for frequency synchronization and can be upgraded to support time-of-day synchronization with a software or firmware upgrade.

Some previously deployed switches and routers may support 1588, while others may not. While 1588 may be supported by most switches and routers deployed within the last few years, it is unlikely that they meet the new ITU profiles for Time and Phase delivery.  IEEE1588 Boundary or Transparent Clocks with distributed time stamping directly at the PHY level will be required to meet these new profiles, and only few routers and switches have this capability today.  Depending where in the network a switch or router is installed, network operators may be able to continue to use GPS to provide synchronization, gradually upgrading routers by using 1588-compliant line cards for all new line card installations and swapping out non-compliant line cards where appropriate.

Wireless network operators should check with small cell, femtocell and switch and router vendors about support for 1588v2 and G.8273.2 if they haven’t already.

About the Author

Martin Nuss joined Vitesse in November 2007 and is the vice president of technology and strategy and the chief technology officer at Vitesse Semiconductor. With more than 20 years of technical and management experience, Mr. Nuss is a Fellow of the Optical Society of America and a member of IEEE. Mr. Nuss holds a doctorate in applied physics from the Technical University in Munich, Germany. He can be reached at nuss@vitesse.com.

About Vitesse
Vitesse (Nasdaq: VTSS) designs a diverse portfolio of high-performance semiconductor solutions for Carrier and Enterprise networks worldwide. Vitesse products enable the fastest-growing network infrastructure markets including Mobile Access/IP Edge, Cloud Computing and SMB/SME Enterprise Networking. Visit www.vitesse.com or follow us on Twitter @VitesseSemi.

Saudi Telecom to Launch TDD LTE-A with Huawei

Saudi Telecom has succeeded Huawei to deploy TDD LTE-Advanced technology in its network.  network to the advanced 4th generation LTE-A network. Financial terms were not disclosed.

"Saudi Arabia is considered as the largest telecom market in the Middle East. Therefore, launching the first quad systems network in the world (GSM/ UMTS/ LTE TDD/ LTE FDD), and upgrading the network to the advanced 4th generation LTE-A, enhances the Internet service in the Kingdom significantly, and offers a new experience for the STC's customers in the field of mobile wireless broadband services," stated Dr. Khaled Albayari, Senior Deputy of STC Group for Technology & Operations.

http://www.huawei.com

Tuesday, February 25, 2014

Deutsche Telekom Drives Network Transformation

Deutsche Telekom is moving as quickly as possible to retire its legacy PSTN and go entirely IP, with the goal of having around 8 million IP-based lines across its footprint in Europe by the end of 2014 and the entire project completed in 2018. It's long term goal is an IP network that integrates mobile and fixed lines across all the European markets in which it operates.

In presentations at Mobile World Congress in Barcelona, Deutsche Telekom executives said this network transformation will also leverage network virtualization technology for service agility and reduced operating costs.

“The growing traffic demands by new mobile access technologies including machine-to-machine and real-time applications require a holistic network approach to improve capacity, efficiency and manage the best-possible customer experience,” said Claudia Nemat. "Innovation in networks is invisible, but customers feel the benefits. It's a revolution that is as radical as the transition from horse and carriage to car."

In mobile, Deutsche Telekom has now launched LTE in almost all of its markets. By 2016, Deutsche Telekom will be able to provide LTE to its customers at every second base station across Europe.

“We don’t only have the expansion of network coverage in mind; we also want to keep increasing the speed of connections. That’s why we’re carrying out tests in Germany, among other places, to see how we can provide customers with data as fast as possible through LTE Advanced,” said Claudia Nemat. “Today I can say that we have reached a point in the LTE rollout in Germany where our customers can use LTE in over 150 cities with speeds up to 150 Mbps,” added Niek Jan van Damme. 300 Mbps will be the next milestone. In a test last week in the German city of Alzey Deutsche Telekom reached even speeds of up to 580 Mbps using LTE-A 4x4 MIMO.

Deutsche Telekom also presented a hybrid router that combines fixed network, LTE and WiFi technologies so as to bundle, concentrate and distribute bandwidth in consumer homes. This project is expected to launch by the end of 2014.

http://www.telekom.com/news/156602

Monday, January 20, 2014

SK Telecom Tests 3-Band LTE-Advanced Carrier Aggregation

SK Telecom has successfully tested LTE-Advanced 3 Band Carrier Aggregation (CA) technology.

The technology aggregates 3 bands – 20MHz+10MHz +10MHz – to support speeds of up to 300Mbps. Client devices will need chipsets capable of aggregating 3 bands.

SK Telecom said its testing help advance the global standardization process for LTE-Advanced 3 band CA.

“With the successful development of “LTE-Advanced 3 Band CA”, SK Telecom further strengthens its global leadership in telecommunications technologies,” said Park Jin-hyo, Senior Vice President and Head of Network Technology R&D Center at SK Telecom. “SK Telecom will continue to make strenuous efforts to provide unmatched service quality and speeds, which will lead to the overall advancement of the global telecommunications industry.

SK Telecom also noted plans to showcase its LTE-Advanced 3 band CA at MWC 2014in Barcelona next month. The company expects its demonstration will achieve 450Mbps by aggregating three component carriers (20MHz+ 20MHz+20MHz).

http://www.sktelecom.com/en/press/detail.do?idx=1054


In November 2013, SK Telecom demonstrated downlink speeds of 225 Mbps by using LTE-Advanced Carrier Aggregation to combine 20MHz bandwidth in 1.8GHz band and 10MHz bandwidth in 800MHz band. For comparison, the carrier's regular LTE service delivers a maximum of 150Mbps of speeds using 20MHz of continuous spectrum in one band.

SK Telecom said its planned upgrade to LTE-Advanced (20MHz+10MHz) will enable mobile customers to download an 800MB movie in just 28 seconds, significantly faster than other networks. Measured at their maximum speeds, downloading the same movie file via 3G, LTE, and the existing LTE-Advanced (10MHz+10MHz) would take 7 minutes and 24 seconds, 1 minute and 25 seconds, and 43 seconds, respectively.

The company said that it expects to launch the ‘20MHz+10MHz’ LTE-Advanced service nationwide through smartphones in the second half of 2014, pending release of LTE-Advanced smartphone chipsets.

Wednesday, January 15, 2014

Ericsson Demos LTE-A Carrier Aggregation with Angola's Unitel

Angola’s leading telecommunications provider Unitel, has successfully tested LTE Advanced (LTE-A) Carrier Aggregation of the 1800MHz and 900MHz spectrum bands on its commercial network.  The demonstration took place on December 18 in Luanda, Angola, in partnership with Ericsson.

Amilcar Safeca, Deputy CEO of Unitel, says: “Unitel is always innovating to enhance the customer experience. With the global leap toward higher data access speeds for sophisticated video and mobility services, we are enhancing our network to ensure we continually provide high-quality services to our high-demanding subscriber base. With this demo, we are well on the way to launching the most advanced mobile network in Angola and perhaps Africa in the near future. We are working with Ericsson to make this happen.”

http://www.ericsson.com/news/140114-unitel-and-ericsson-demo-africas-first-lte-advanced-technology_244099438_c

Sunday, October 6, 2013

Anite Launches LTE-A Carrier Aggregation Network Testing Solution

Anite announced the commercial release of an LTE-A and carrier aggregation ("CA") testing solution for mobile network operators and network infrastructure vendors.

Anite said LTE-A CA measurements with its Nemo Outdoor provide detailed information about the primary and secondary component carriers, including physical cell ID, signal levels and quality. Also link adaptation and radio resource allocation can be monitored among many other detailed LTE parameters.

"Staying ahead in a fast-changing competitive environment means being first to deliver new functionality. The launch of LTE-A carrier aggregation testing with Nemo Outdoor underlines Anite's leadership in cutting-edge technologies" says Petri Toljamo, Managing Director at Anite's Network

Testing business. He continues, "Key industry players are already preparing for LTE-A and carrier aggregation deployments. With our help operators can make sure their networks are optimised for providing the high data rates their customers are demanding."

http://www.anite.com/nemo

Tuesday, September 3, 2013

KT Gains 1.8 GHz Spectrum for LTE-A Launch

KT is preparing to launch LTE-A service this month using carrier aggregation technology to achieve downlink speeds of up to 150 Mbps.  The Korean operator secured the 1.8 GHz frequency band at auction last week. The license covers 20 MHz in the band.
KT, which currently has about 6.5 million LTE subscribers, plans a nationwide rollout over the coming months, beginning in Seoul.

The company has about 100,000 base stations ready for upgrade.

KT also claims its LTE-A will be more energy efficient at the handset, enabling longer battery life for end users.

http://lte-a.olleh.com/lte/a/main.asp
http://www.kt.com


In August, SK Telecom announced an expansion of its LTE-Advanced commercial service network, via its local entity Ericsson-LG, to downtown areas of 84 cities nationwide, including the entire Seoul metropolitan area and six other major cities.  The carrier launched its commercial LTE-Advanced service earlier this summer, offering up to 150Mbps mobile broadband speeds, twice that of LTE.  The initial launch included the entire Seoul area, the downtowns of 42 cities in Gyeonggi-do and Chungcheong-do provinces, and 103 campus towns.

SK Telecom plans to deploy 32,000 LTE-Advanced base stations by the end of the year, which will cover 84 cities nationwide and approximately 300 college campuses.

Ericsson confirmed its major role in the SK Tel upgrade, providing the software for Carrier Aggregation and multi-carrier technology for the B5 (850MHz) and B3 (1.8GHz) bands in South Korea’s southeastern regions, where Ericsson partnered with SK Telecom for the LTE network deployment and commercial service launch in 2011.

Thursday, February 28, 2013

Huawei's FusionNet for LTE-B Envisions 500% Gains

At Mobile World Congress, Huawei outlined its "FusionNet" next generation network architecture for LTE-B.

The company believes it can improve Cell Edge User (CEU) throughput by at least 500% with a series of multi-RAT, multi-band and multi-layer HetNet enhancements.

Huawei’s FusionNet concept for LTE-B comprises several core technologies, including multi-stream aggregation, interference coordination, traffic adaption and spectrum efficiency optimization. Existing LTE and LTE-A deployments and technologies (including CoMP and carrier aggregation) will be coordinated.

Also at MWC 2013, Huawei unveiled its Ultra Node prototype design for future mobile broadband base stations. Huawei said its Ultra Node enhances the spectrum utilization and overall network efficiency to achieve a 50 Gbps peak data speed in a single node.

Huawei also noted that since 2010 it has contributed 362 LTE, LTE-A and LTE-B proposals for 3GPP LTE standards, accounting for nearly 20% of the global total and more than any other contributor.

http://www.huawei.com

Thursday, February 21, 2013

NTT Docomo Develops LTE-A C-RAN Architecture

NTT DOCOMO will begin developing high-capacity base stations built with advanced Centralized Radio Access Network (C-RAN) architecture for its next-generation LTE-Advanced (LTE-A) mobile system.

The carrier is looking to accelerate the deployment of base stations, especially in high-traffic areas such as train stations and large commercial facilities, for significantly improved data capacity and throughput.

The new C-RAN architecture will enable small "add-on" cells for localized coverage to cooperate with macro cells that provide wider area coverage. This will be achieved with carrier aggregation technology, one of the main LTE-Advanced technologies standardized by the Third Generation Partnership Project (3GPP).

High-capacity base stations utilizing advanced C-RAN architecture will serve as master base stations both for multiple macro cells covering broad areas and for add-on cells in smaller, high-traffic areas. The base stations will accommodate up to 48 macro and add-on cells at launch and even more later. Carrier aggregation will be supported for cells served by the same base station, enabling the flexible deployment of add-on cells. In addition, maximum downlink throughput will be extendible to 3Gbps, as specified by 3GPP standards.

Docomo estimates that the small add-on cells will significantly increase throughput and system capacity while maintaining mobility performance provided by the macro cell.

http://www.nttdocomo.com/pr/2013/001633.html

NTT Docomo Tests Active Antennas for LTE-A

NTT DOCOMO successfully connected an active antenna to a commercially operational LTE base station.

Active antennas are expected to be widely used in LTE and LTE-Advanced base stations to improve range and lower power consumption.

The antenna, jointly developed by Tokyo-based Nihon Dengyo Kosaku Co., Ltd. and Ubidyne GmbH of Germany, was connected to a DOCOMO LTE base station via an ORI-standard interface.

The base station used in the experiment is a remote installation-type base station comprising one master station and multiple secondary stations. A conventional secondary station is equipped with an antenna and separate remote radio heads (RRH) for sending and receiving signals. An active antenna, however, has a built-in RRH, allowing the secondary station to be smaller in size and installed in more confined spaces, resulting in denser LTE coverage and reduced installation costs.

DOCOMO said the experiment indicates that it eventually will be able to install active antennas quickly and inexpensively without having to set up new base stations. DOCOMO already operates base stations that use the ORI interface, a specification of the European Telecommunications Standards Institute.

http://www.nttdocomo.com/pr/2013/001636.html

Wednesday, February 20, 2013

Altair's Latest Silicon Supports LTE Release 10

Altair Semiconductor unveiled a new family of chipsets, including two new baseband processors - the FourGee-3800 and FourGee-3802 - and a new radio chip - the FourGee-6300.

Key features of the new chipset family include:
  • Support for LTE Release-10 features
  • Based on Altair's 3rd generation SDR architecture, software upgradable to future Release-11
  • Category 4 throughput 150 Mbps DL / 50 Mbps UL
  • Support for Carrier Aggregation (CA)
  • High performance 700MHz network processor subsystem
  • Wide frequency band span of 400-3800MHz with 6 concurrent LTE bands for both primary and diversity antennas, enabling global band combinations
  • Integrated IMS/VoLTE with support for HD-Voice
  • Incorporates Altair's proprietary interference cancellation (INCA™) technology
  • Incorporates Envelope Tracking (ET) technology
  • Supports enhanced Inter-cell Interference Coordination (eICIC)  
  • Ultra low Active and Idle power consumption
  • Rich set of host and peripheral interfaces to support a variety of applications including smartphones, tablets, mobile hotspots, routers and M2M.

Thursday, January 31, 2013

ZTE: LTE Carrier Aggregation Test Peaks at 223 Mbps

China Mobile completed a carrier aggregation test in a commercial environment in partnership with ZTE. Carrier aggregation, which is a core component of LTE-Advanced, combines two or more carriers into one channel in the same or different frequency bands.

The test took place in an outdoor TD-LTE network environment and achieved a peak single-user download rate of 223Mbps at an uplink and downlink sub-frame ratio of 1:3. The special time slot ratio during the test was 10:2:2. The test also utilized carrier aggregation (20M+20M) technology to verify key technical points like cell peak rate and mobility.

http://wwwen.zte.com.cn/en/press_center/news/201301/t20130131_385448.html

Thursday, September 27, 2012

Huawei Tests LTE-A Uplinks with CoMP


Huawei has completed the first LTE-A uplink coordinated multi-point (CoMP) trial on several commercial LTE networks in Europe and Asia.

Huawei said its testing revealed that uplink CoMP can effectively double data rates at cell edges for a single user, improving network performance in terms of coverage, spectrum efficiency and throughput.

The company has previously demonstrated LTE-A inter-band carrier aggregation (CA) and heterogeneous networks (HetNet).

"This is a key milestone for the LTE industry," said Ying Weimin, Huawei President for GSM/UMTS/LTE Networks. "Our No-Edge Network concept utilizes various LTE, LTE-A and innovative future-oriented technologies to realize ultra-broadband, zero-waiting and ubiquitous connectivity. This results in an enhanced experience and brings users the benefits of speed, quality and simplicity."

http://www.huawei.com