Showing posts with label Softbank. Show all posts
Showing posts with label Softbank. Show all posts

Tuesday, 21 July 2015

TDD-FDD Joint Carrier Aggregation deployed

As per Analysis Mason, of the 413 commercial LTE networks that have been launched worldwide by the end of 2Q 2015, FD-LTE accounts for 348 (or 84%) of them, while TD-LTE accounts for only 55 (or 13%). Having said that, TD-LTE will be growing in market share, thanks to the unpaired spectrum that many operators secured during the auctions. This, combined with LTE-A Small Cells (as recently demoed by Nokia Networks) can help offload traffic from hotspots.

Light Reading had an interesting summary of TD-LTE rollouts and status that is further summarised below:
  • China Mobile has managed to sign up more than 200 million subscribers in just 19 months, making it the fastest-growing operator in the world today. It has now deployed 900,000 basestations in more than 300 cities. From next year, it is also planning to upgrade to TDD+ which combines carrier aggregation and MIMO to deliver download speeds of up to 5 Gbit/s and a fivefold improvement in spectrum efficiency. TDD+ will be commercially available next year and while it is not an industry standard executives say several elements have been accepted by 3GPP. 
  • SoftBank Japan has revealed plans to trial LTE-TDD Massive MIMO, a likely 5G technology as well as an important 4G enhancement, from the end of the year. Even though it was one of the world's first operators to go live with LTE-TDD, it has until now focused mainly on its LTE-FDD network. It has rolled out 70,000 FDD basestations, compared with 50,000 TDD units. But TDD is playing a sharply increasing role. The operator expects to add another 10,000 TDD basestations this year to deliver additional capacity to Japan's data-hungry consumers. By 2019 at least half of SoftBank's traffic to run over the TDD network.

According to the Analysis Mason article, Operators consider TD-LTE to be an attractive BWA (broadband wireless access) replacement for WiMAX because:

  • most WiMAX deployments use unpaired, TD spectrum in the 2.5GHz and3.5GHz bands, and these bands have since been designated by the 3GPP as being suitable for TD-LTE
  • TD-LTE is 'future-proof' – it has a reasonably long evolution roadmap and should remain a relevant and supported technology throughout the next decade
  • TD-LTE enables operators to reserve paired FD spectrum for mobile services, which mitigates against congestion in the spectrum from fixed–mobile substitution usage profiles.

For people who may be interested in looking further into migrating from WiMAX to TD-LTE, may want to read this case study here.

I have looked at the joint FDD-TDD CA earlier here. The following is from the 4G Americas whitepaper on Carrier Aggregation embedded here.

Previously, CA has been possible only between FDD and FDD spectrum or between TDD and TDD spectrum. 3GPP has finalized the work on TDD-FDD CA, which offers the possibility to aggregate FDD and TDD carriers jointly. The main target with introducing the support for TDD-FDD CA is to allow the network to boost the user throughput by aggregating both TDD and FDD toward the same UE. This will allow the network to boost the UE throughput independently from where the UE is in the cell (at least for DL CA).

TDD and FDD CA would also allow dividing the load more quickly between the TDD and FDD frequencies. In short, TDD-FDD CA extends CA to be applicable also in cases where an operator has spectrum allocation in both TDD and FDD bands. The typical benefits of CA – more flexible and efficient utilization of spectrum resources – are also made available for a combination of TDD and FDD spectrum resources. The Rel-12 TDD-FDD CA design supports either a TDD or FDD cell as the primary cell.

There are several different target scenarios in 3GPP for TDD-FDD CA, but there are two main scenarios that 3GPP aims to support. The first scenario assumes that the TDD-FDD CA is done from the same physical site that is typically a macro eNB. In the second scenario, the macro eNB provides either a TDD and FDD frequency, and the other frequency is provided from a Remote Radio Head (RRH) deployed at another physical location. The typical use case for the second scenario is that the macro eNB provides the FDD frequency and the TDD frequency from the RRH.

Nokia Networks were the first in the world with TDD-FDD CA demo, back in Feb 2014. In fact they also have a nice video here. Surprisingly there wasnt much news since then. Recently Ericsson announced the first commercial implementation of FDD/TDD carrier aggregation (CA) on Vodafone’s network in Portugal. Vodafone’s current trial in its Portuguese network uses 15 MHz of band 3 (FDD 1800) and 20 MHz of band 38 (TDD 2600). Qualcomm’s Snapdragon 810 SoC was used for measurement and testing.

3 Hong Kong is another operator that has revealed its plans to launch FDD-TDD LTE-Advanced in early 2016 after demonstrating the technology on its live network.

The operator used equipment supplied by Huawei to aggregate an FDD carrier in either of the 1800 MHz or 2.6 GHz bands with a TDD carrier in the 2.3 GHz band. 3 Hong Kong also used terminals equipped with Qualcomm's Snapdragon X12 LTE processor.

3 Hong Kong already offers FDD LTE-A using its 1800-MHz and 2.6-GHz spectrum, and is in the midst of deploying TD-LTE with a view to launching later this year.

The company said it expects devices that can support hybrid FDD-TDD LTE-A to be available early next year "and 3 Hong Kong is expected to launch the respective network around that time."

3 Hong Kong also revealed it plans to commercially launch tri-carrier LTE-A in the second half of 2016, and is working to aggregate no fewer than five carriers by refarming its 900-MHz and 2.1-GHz spectrum.

TDD-FDD CA is another tool in the network operators toolbox to help plan the network and make it better. Lets hope more operators take the opportunity to deploy one.

Thursday, 7 February 2013

The story of Femtocells, Small Cells and Metrocells

Femtocells were introduced many years back as a residential, closed group, small base station. The intention was to provide coverage at home for high speed data (primary) and voice (secondary). It was more for coverage than capacity. In these good old days smart phones were far and few and feature phones were many. WiFi on the phone made it expensive and power hungry so cellular was the way to go.

There were many opportunities for Femtocells to take the centre stage as the concept is technologically sound but the operators have been not very willing to deploy it soon enough. Some operators were more willing to give it a try to fix their own issues, for example Softbank which gave free femtocells, in open access mode, to improve its coverage issues. Femtozone services that promised value addition provided with the Femtocells, never took off. Other promises of exclusive broadcast content using Femtocells for example never materialised due to lack of availability of the handsets and content.

Lot has changed since then. The smartphones and tablets have taken over the market, all of them have inbuilt WiFi that is generally more efficient than the cellular radio, coverage issues have become secondary and capacity issues are a bigger concern. Femtocell players have realised that except for the publicity, there isn't much to gain from the Femtocells. As a result Femtocells were replaced by the term Small cells that represents much more than the old Femtocells. The residential Femtocells have been reduced to being just voice boosters.

The different types of Small cells can be seen in the picture above. Except for the residential, the other types of small cells operate in either the open mode or the hybrid mode. Personally, I differentiate closed Femtocells from the other Small Cells. Metrocell is the upcoming type of Small cell that I believe everyone is focussing on. They operate always in the open mode and have been chosen as the promised one to solve the two major problems of capacity and coverage.

According to the Small Cell Forum introductory whitepaper, Metrocells would see an increased growth in the next few years when the operators start deploying more of them and less of the Macrocells.

So for those of you who don't know, and would like to learn more, an introductory presentation on Metrocells is available here.

If this is an area of interest and you are interested in having and in-depth understanding then we invite you to attend our Metrocells Masterclass which is a one day workshop explaining ins and outs of Metrocell. 

If you are a big organisation and would like us to provide you with a private workshop, please feel free to contact us for details.

We have also started the Metrocells Blog that I will use to post information related to Small Cells and Metrocells in future. Please feel free to take a look at:

Wednesday, 28 March 2012

Platinum Band: Sub 1GHz Frequency Band

Was listening to the Softbank webcast earlier about why they are so happy on receiving the 900MHz spectrum. The extract from slidepack summarises the advantages on this 'Platinum Band'

Tuesday, 21 February 2012

Softbank Japan's Ultra Wifi 4G (a.k.a AXGP)

In Japan, they love to re-brand the standard technologies into something more interesting to attract people's attention. In a way they are right as they want to offer a service rather than a technology. Couple of years back NTT Docomo launched its Crossy service, that was offering LTE with upto 75Mbps dl speeds. Yesterday, I read about Softbank launching their 4G service that is based on AXGP format.

I did blog about XGP many years back but AGXP, which stands for Advanced XGP may not be very well related to XGP. According to ZTE Technologies magazine:

In November 2011, Japan’s third largest mobile operator, Softbank, made AXGP commercially available. AXGP is similar to TD-LTE, and has been deployed in Japan in conjunction with ZTE and Huawei. Two thousand base stations were built in the fi rst phase, and there will be up to 10,000 base stations built in the second phase. Ninety-nine percent of the Japanese population will be covered by 2012. So far, the Softbank network is the largest commercial TD-LTE network in the world. Wang Jianzhou, chairman of China Mobile, said, “If in the past the TD-LTE network was just a stratagem on paper, now it has turned into a reality.”

The following are some more details edited from a Japanese website (translation via Chrome):

High-speed data communication service Wireless City Planning of the SOFTBANK Group (Wireless City Planning, WCP) will be scheduled after February 2012, adopted a new communication method AXGP is, in excess of up to 100Mbps downlink high-speed communication is a feature . It was an opportunity to use the test machine prior to the start of service for general users, to report a sense of its use. 

 "AXGP" was developed inherit the "PHS" next generation of Willcom

 "AXGP" high-speed data transmission technology WCP employs a technology that was originally planned to use the 2.5GHz band has been assigned from the Ministry of Internal Affairs and Communications Willcom to deploy as "PHS" next generation. Had to expand the limited service area and some intended for users under the name of "WILLCOM CORE XGP" PHS is then the next generation, business is XGP is "Wireless City Planning" of Softbank subsidiary company under the reorganization proceedings of Willcom inheritance. Provide the service as "AXGP" form of communication is an evolved version of XGP in WCP.

 AXGP, in addition to the XGP also hand while inheriting the "micro cell" was characteristic of PHS, PHS has been developed as the next generation, that have become compatible with the method of TD-LTE. Including China and India, that are compatible with the TD-LTE system is expected to expand in many parts of the world, the benefits can be expected that international expansion is expected. 

 Service is initially started up to 76Mbps. The first bullet is the mobile router products

 AXGP is at present, but services have been provided for users in a small part had been using the service test XGP Willcom old, since the February 2012 service "SoftBank 4G for general users as MVNO Softbank Mobile plans to start ". The communication speed up to 110Mbps downstream and 15Mbps and maximum upstream and downstream speeds in excess of 100Mbps for speed has become a feature.

 At the start of service, the mobile router will "101SI" made of (SII) will be released at the same time Seiko Instruments. However, 101SI has become a maximum 76Mbps to 110Mbps falling down is the theoretical value of the service, at the start of the service is not provided in the full spec. Terminal is planned to also provide support AXGP Then, in the year 2012 is also powered smartphone will be compatible with AXGP. In addition, "101SI" to support (42Mbps maximum downlink, 5.7Mbps uplink maximum) "ULTRASPEED" Softbank mobile. 

Ultra-high speed in the area. Hope to plan area at the time of service and rates

 Although a measurement with the outdoor area was limited, with respect to communication speed was very good results with the results fit. Most favorable conditions and even the user does not exist before the start of the service say that already provide services as high-speed data communication, "Xi" of NTT DoCoMo, Inc., or UQ Communications 37.5Mbps, which is the maximum theoretical value of outdoor (Kurosshi~i) It was also a number greater than the maximum 40Mbps "UQ WiMAX" of is very encouraging.

 However, the decisive factor in mobile data communications is not only communication speed, three elements of the communication charge is important and easy-to-use, deployment area, including "ease of connection." In the area at the moment of some are very fast and are limited in the Yamanote Line, but is a matter of course in order before the service, ease of connection of the fact there are many parts of the still unknown. Also, I'd be anxious and services are provided in the fee structure what.

 SoftBank is to introduce a flat-rate voice among their users ahead of any other mobile phone operators so far, campaigns expand the iPhone however any inexpensive flat-rate packet. Further has a track record of just made me started to increase subscribers by the "straight-line with anyone" WILLCOM has also continued to decline in subscribers. Softbank Mobile also be deployed as a MVNO, at the time of release of the service that you want to use the AXGP expect a bold expansion of unique services and Softbank WCP, which is the same group Softbank.

Softbank's website is billing this as 'Ultra Wifi 4G' and will be launched to public this Friday, just in time for MWC12.