Showing posts with label 4G. Show all posts
Showing posts with label 4G. Show all posts

Monday 28 September 2009

ICC 2009: 3G to 4G: towards full mobility IP services


There are some interesting slides and presentation from the IEEE Communications Society ICC 2009 conference in Dresden, Germany in June 2009. Here is the link to slides from the topic "3G to 4G: towards full mobility IP services".
Let me know if you found it useful.

Monday 24 August 2009

3G or 4G: What should India do?

The first thing I should mention as I always do, please stop calling LTE as 4G as its commonly called as 3.9G. Labelling it as 4G does make it sound better (or sexy, some would say) but its not correct. Maybe the authors who label LTE as 4G dont want to try hard and do some research or its just to make the end users panic that India has missed a complete generation of mobile technology. LTE-Advanced will be the 4G technology and its still long way away (part of Rel-10).

Last week I wrote about Indian subscribers getting taste of 3G as the state owned MTNL and BSNL have launched some services. I am not sure what has been launched but all I can say is there is a dismal takeup as of yet. I read an article today about how Motorola is testing 4G [sic] and this can spoil the governments plan of rasing Rs 35,000 crore (£4.6Billion: 1Billion = 100 crores).

People may start panicking that investing in 3G is now doomed and it can just cause problems for the operators in future. The reality though is much more simpler. In a simple sentence, I would say that going for 3G or LTE does not matter much. Read on.

Lets first get Hardware out of the way. Most of the Base Stations (NodeB's, eNodeB's, RNC, etc) have a major part as SDR's or Software Defined Radios. The advantage of this is that if you have bought a 3G Node B, with just software change it should be upgradable to LTE eNode B. I have come across quite a few products where the equipment manufacturers are claiming that their 3G equipment is fully upgradeable to LTE. I did blog about some of this in this post here.

The second point we should get out of the way is the terminology. For a layman, 3G is something that was introduced 10 years back in 2000 so its quite an obsolete technology. In reality, 3G is commonly used to refer to even the new developments within the 3G spectrum. For example some of the people may have heard of HSDPA which is actually referred to as 3.5G in the mobile domain. Similarly we have HSUPA which is 3.75G and so on. The latest development is going on around 3.8G and 3.85G as part of Release 8. In general usage 3.5G, 3.75G, etc. is referred to as 3G but its more than 3G (3G+ ;). The good thing is that this 3G+ is till evolving. Release 8 was finalised in Dec. 2008 and the terminals based on that are still being tested. It should hopefully be available soon.

So whats the difference between LTE and HSPA+ (also known as 3G even though its 3.8/3.85G). Not much I would say from a general users point of view. Please note I am not arguing about the fundamental technologies because 3G+ uses WCDMA and LTE uses OFDMA/SC-FDMA technologies. OFDM based technologies will generally be always superior to WCDMA ones but it doesnt matter much. The main enhancement that has happened with LTE as compared to 3G is that in 3G the bandwidth is fixed to 5MHz whereas in case of LTE the bandwidth is flexible and can go all the way to 20MHz. Now if we compare the data speeds in 5MHz spectrum then there may not be much difference between them. Now how many operators will be rolling out services across 20MHz bandwidth? More general case will be using 10MHz.

In case of HSPA+, there is a new feature that allows a UE to use couple of cells. In this case even though the bandwidth is 5MHz but due to Dual Cell feature the UE would effectively see 10MHz bandwidth. This will definitely enhance the speeds.

Now coming to devices. 3G/HSPA/HSPA+ technologies have evolved over quite few years. There are some nice sleek and cheap handsets available. The technology in it as been rigourously tested. As a result the handsets are quite stable and many different design and models available.

LTE is yet to come. NTT DoCoMo and Verizon will be the first one to roll it out probably end 2010. Initial plan is to roll out the dongles then handsets will the eventually arrive. The initial ones will have problems, crashes, etc. Will take atleast till 2010 to sort out everything.

The big problem with LTE as many of us know is that the standards have to support for the old style CS voice and SMS. This should be fixed in Release 9 which is going to be standardised in Dec. 2009 (Mar. 2010 practically). There are different approaches and maybe untill LTE is rolled out we wont know which of them is better.

Last thing I should mention is the spectrum. The consensus is that 3G operates in 2.1GHz spectrum mostly worldwide. LTE would initially be deployed in 2.6GHz spectrum. The digital dividend spectrum when it becomes available will also be used for LTE. Most of the devices for LTE will be designed that way. As a result, 3G will continue to operate as it is in the 2.1GHz band. The devices will always be available and will be usable for long time.

Considering all the facts above, I think 3G (HSPA/HSPA+) is the best option in India or as a matter of fact in any country that is thinking of jumping directly from 2G to LTE. When the time is right, it should not be difficult to move from 3G to LTE.

Saturday 11 July 2009

LTE and 4G IPR

The other day I heard from Alex GeunHo Lee about his new blog related to 4G technologies IPR. Alex has got extensive experience in IPR and patent related issues and I am sure his blog will be very useful for everyone.

Couple of Alex's presentations are embedded below which I am sure many would find interesting.

LTE Essential Patents Landscape 2009 2Q



4G Key Technologies Patent Landscape 2Q 2009


Monday 13 October 2008

What on earth is this 4G, anyway?

Over the past two years I have been hearing a lot about next generation technologies. It all started by 3.5G i.e. HSPA evolution etc and hence the debate entered into the area of 4G.
Everybody comes along on the blogs, articles, tech magazines etc and make himself/herself comfortable as per their liking with the word 4G.

Some people use the term "4G" to describe WiMAX technology. This terminology i.e. 4G used by WiMax camp does indeed upset some people specially the ones in the LTE camp.

Everyday I come across individuals who have different view regarding the 4G terms. Some do shockingly tell me that neither WiMax nor LTE is a 4G technology rather LTE evolution or LTE advanced will be termed as a 4G technology.

I have literally reached to stage now where I think I should give up now and just leave to almighty to decide what actually a 4G technology is. If you ask me about my personal opinion on this then my view is quite clear in this. I categorize 1G as analog mobile, 2G as digital, 3G as CDMA, and 4G as anything using OFDM. It's pretty simple, it is straightforward, there's not a lot of haggling.

Wikipedia says "There is no formal definition for what 4G is; however, there are certain objectives that are projected for 4G. These objectives include: that 4G will be a fully IP-based integrated system. 4G will be capable of providing between 100 Mbit/s and 1 Gbit/s speeds both indoors and outdoors, with premium quality and high security."

By the Wikipedia definition, three out of four definitions are met under the existing definitions of WiMAX; nobody thinks that the current definition of WiMAX is going to be able to crank up to 1 Gbit/sec, but life, as they say, ain't so simple.

A spokesperson for Nokia has said "There's no official owner of who defines 4G," and you would think if anyone could tell you what 4G was/is/will be, it would be Nokia.

ITU-R is in the process of defining IMT-Advanced, but, funny enough, the standards body has backed away from the phrase 4G. IMT-Advanced is a "big tent" term that will/may/should encompasses 802.16m and LTE-Advanced which in turn are faster than WiMAX and LTE standards respective. Maybe?

If I understand this descent into acronyms and definitions, even the forthcoming, first generation LTE would not qualify as a 4G technology. That is, if we call IMT-Advanced as the term formerly known as 4G - but not called 4G by ITU-R.

I know this whole argument of 4G terms upset many people. They think and rightly so that the whole concept behind a 'Standards Body' is so that such arguments are moot. These guys think that people use different terms to coin their own standards for marketing, one-upmanship and generally nonconformist attitudes.

Well let's hope that some day somebiody will come out with a clear idnetity of the 4G technology which is acceptable to everybody. Meanwhile my friend in the picture above is working hard to find out what 4G really is.

Tuesday 7 October 2008

Nortel 4G: Cracks in the wall

Sometime in distant past, it seemed that Nortel had everything. They were big in UMTS and HSPA, had a share of CDMA pie in Americas, had loads of patents in OFDM technology which is the basis of most Next Generation technologies, had strategic partnership and very much into R&D on WiMAX and LTE and at the same time also working on 4G Optical technologies.

Then they got rid of 3G and HSPA infrastructure by selling it to Alcatel (now Alcatel-Lucent) and started focussing on 4G only. Then their CDMA business started to suffer because people in Americas are moving onto GSM and CDMA growth opportunities are limited. Recently Nortel has again been in news because it wants to sell its Metro Ethernet Networks (MEN) business.


The MEN division includes Nortel's optical business and its carrier Ethernet work, including its Provider Backbone Transport (PBT) technology. That's big news, but so is the lowered forecast. After predicting single-digit sales growth this year, Nortel is now saying its 2008 revenues will be 2 to 4 percent less than the $10.95 billion it reported in 2007.

According to a report in Unstrung, Nortel isn't so keen on developing LTE either, despite repeated claims that it was well positioned to be a major player in that market. When asked during analyst conference call about what actions Nortel might take regarding its 4G developments, CEO Mike Zafirovski said the company is looking for "opportunities to de-risk" its investment. "Future consolidation is necessary in wireless. We're exploring options for 4G that will be best" for Nortel, its customers, and the industry, said the CEO, unhelpfully.

What might those options be? Zafirovski said that "what we did with UMTS and Wimax" are examples of what might happen. Nortel's WiMax strategy is now tied up in the Alvarion relationship, while it sold its 3G UMTS infrastructure business to Alcatel in late 2006.

Analysts, still parsing Nortel's words, see some value in Nortel getting help from partners. “Ever since Nortel exited the UMTS market it’s been next to impossible to see how investing in their own LTE base station would result in anything but huge losses," says Patrick Donegan, Heavy Reading's senior wireless analyst. "Going down the same OEM path as they have with WiMax would at least ensure that those huge losses won’t be suffered. Whether they can go beyond that and carve out a position in LTE which is actually profitable with an OEM partner is unclear but certainly plausible.”

But, just like with carrier Ethernet and optical, the market is too tough for Zafirovski to believe Nortel can be a leading and profitable player. "With eight, nine, ten players competing, industry dynamics require various forms of cooperation," he added.

Despite all the predictions and Hype, 4G or LTE is far away. WiMAX will be rolled out but in chunks and there are already too many people in WiMAX. What Nortel needs and is looking for is some significant partner or perhaps a merger (takeover?). In the meantime it maybe some time before its investors hears any good news from Nortel.

Friday 12 September 2008

eHRPD: Stopgap between EV-DO and LTE

Interesting article from TMCnet.

As LTE is picking up steam, more and more operators opting for this technology. It is but natural that some CDMA2000 operators would like to joing the camp as well. Since there is no clear evolution path available from CDMA2000 to LTE, a soft option is required so that there is no immediate need to change the complete infrastructure and in case of any problems suffer.

The transition for CDMA operators from High Rate Packet Data (HRPD) to LTE will be over a period of several years, as is the case still with the transition from 1xRTT to HRPD. As a result, mobile operators must look for a migration path that will enhance their existing HRPD networks, while addressing LTE deployment requirements and will not require a ‘forklift’ upgrade.

The choice of migration path depends on many factors including radio access strategy, network resource strategy, services enabled, timing and cost. A key goal of LTE is to enhance service provisioning while simplifying interworking with non-3GPP mobile networks. This is essential for CDMA operators that have chosen to migrate to LTE.

Evolved HRPD is a method that allows the mobile operator to upgrade their existing HRPD packet core network using elements of the SAE/EPC architecture. Additionally, eHRPD is a more evolutionary path to LTE while also allowing for seamless service mobility — including seamless hand-offs — between the eHRPD and LTE networks.


One of the main advantages of eHRPD is the ability to provide seamless service mobility between HRPD and LTE access networks with a single mobility management protocol. Moreover, with eHRPD, the operator can leverage the benefit of optimized handover – no dropped sessions and reduced handover latency — between LTE and eHRPD. The benefit of seamless and optimized mobility for data is highly dependant on the mobile operator business model for adding new services. As new applications emerge, the requirement for seamless service mobility becomes greater. Since SAE is an all-IP network infrastructure, the network will quickly move to mobile VoIP for voice. Moreover, with the introduction of eHRPD, the operator can leverage the benefit of optimized intra eHRPD handover when the user crosses the HSGW boundaries. This capability does not exist in current HRPD systems.

You can read the complete article here.

Wednesday 10 September 2008

Japan to trial its own 4G Technology

While we were focussing on the battle between LTE and WiMAX having already forgotten about UMB, Japan has been working on its Next G of PHS called the XGP.


The news came to light in ITU Telecom Asia, which concluded recently.


PHS was popular in Japan earlier on because it was very cheap and easy to deploy in the old days when other technologies were expensive. The main drawback it has is that it is not easy to perform handovers so the calls may drop while in the subway.

PHS operator WillCom has won, one of the spectrum block in 2.5GHz band and is going to start trials next April in Tokyo, Nagoya and Osaka and offer 20Mbps of symmetrical data speeds using a 10MHz spectrum block. A full commercial service is scheduled for August 2009.
The service will be known as WILLCOM CORE (Communication Of Revolution and Evolution)
The technology behind is based on the PHS architecture of numerous microcells offering limited coverage, but will incorporate a new air radio interface based on OFDMA/TDMA/TDD methodologies. Kyocera and UTStarcom will manufacture the radio access equipment for XGP while NEC Infrontia and NetIndex are developing the data card modules for the service. Canada’s Wavesat and Israel’s Altair is supplying the baseband chips for XGP. Like LTE and WiMAX, XGP will support viable spectrum blocks.

But while LTE and WiMAX are based on increments of 1.6MHz for its carrier size, XGP has aligned itself with CDMA and supports increments of 1.25MHz carriers.

With a basic 10MHz carrier system, XGP will offer data speeds of 20Mbps, but future systems incorporating MIMO and SDMA (space division multiple access) will be capable of supporting maximum symmetrical data speeds of 100Mbps. At the same time, the technical description for XGP will support handoffs between base stations for users travelling at up to 300 km/h.

A good presentation from Willcom on XGP is available here.

PHS = Personal Handyphone System

Friday 22 August 2008

802.11n and 4G...

IEEE 802.11n is a proposed amendment to the IEEE 802.11-2007 wireless networking standard to significantly improve network throughput over previous standards, such as 802.11b and 802.11g, with a significant increase in raw (PHY) data rate from 54 Mbit/s to a maximum of 600 Mbit/s. Most devices today support a PHY rate of 300 Mbit/s, with the use of 2 Spatial Streams at 40 MHz. Depending on the environment, this may translate into a user throughput (TCP/IP) of 100 Mbit/s.

According to the book "WI-Fi, Bluetooth, Zigbee and Wimax":

802.11n is the 4th generation of wireless lan technology.
  • First generation (IEEE 802.11) since 1997 (WLAN/1G)
  • Second generation (IEEE 802.11b) since 1998 (WLAN/2G)
  • Third generation (802.11a/g) since 2000 (WLAN/3G)
  • Fourth generation (IEEE 802.11n) (WLAN/4G)

The distinguishing features of 802.11n are:

  • Very high throughput (some hundreds of Mbps)
  • Long distances at high data rates (equivalent to IEEE 802.11b at 500 Mbps)
  • Use of robust technologies (e.g. multiple-input multiple-output [MIMO]and space time coding).

In the N option, the real data throughput is estimated to reach a theoretical 540 Mbps (which may require an even higher raw data rate at the physical layer), and should be up to 100 times faster than IEEE 802.11b, and well over ten times faster than IEEE 802.11a or IEEE 802.11g. IEEE 802.11n will probably offer a better operating distance than current networks. IEEE 802.11n builds upon previous IEEE 802.11 standards by adding MIMO. MIMO uses multiple transmitter and receiver antennae to allowfor increased data throughput through spatial multiplexing and increased range by exploiting the spatial diversity and powerful coding schemes. The N system is strongly based on the IEEE 802.11e QoS specification to improve bandwidth performance. The system supports basebands width of 20 or 40MHz.

Note that there is 802.11n PHY and 802.11n MAC that will be required to acheive 540Mbps.

To achieve maximum throughput a pure 802.11n 5 GHz network is recommended. The 5 GHz band has substantial capacity due to many non-overlapping radio channels and less radio interference as compared to the 2.4 GHz band. An all-802.11n network may be impractical, however, as existing laptops generally have 802.11b/g radios which must be replaced if they are to operate on the network. Consequently, it may be more practical to operate a mixed 802.11b/g/n network until 802.11n hardware becomes more prevalent. In a mixed-mode system, it’s generally best to utilize a dual-radio access point and place the 802.11b/g traffic on the 2.4 GHz radio and the 802.11n traffic on the 5 GHz radio.


A lot of phones are coming with inbuilt WiFi (or 802.11 a/b/g) and this WiFi is a must on Laptops or they wont sell. The main difference in 802.11n, compared to previous generation of 802.11 is that there is a presence of MIMO. 802.11 family uses OFDM which is the same technology being adopted by LTE. The new LTE handsets will have advantage of easily integrating this 802.11n technology and the same antennas can be reused. In fact the same is applicable for WiMAX as it supports MIMO and OFDM. Ofcourse we will have problems if they are using quite different frequencies as the antennas ore optimised to range of frequencies, this is something that has to be seen.

In the news:

MIT and a medical center based in Alabama are beginning to deploy faster wireless 802.11n access points from Cisco Systems Inc. In more than 100 buildings on MIT's Cambridge, Mass., campus, as many as 3,200 access points running older 802.11a/b/g protocols will be replaced with 802.11n devices in the next 12 to 16 months, said Chris Murphy, a networking engineer at the university. Murphy said MIT, with more than 10,000 students and 11,000 staff members, has a "very, very wide variety" of client devices, from handhelds to laptops. Many of the laptops probably support the 802.11n protocol, he said. Some MIT staffers have been using voice-over-IP wireless handsets and have experienced poor coverage with the older Wi-Fi technology, but they said they have had full signal strength within the range of the new 802.11n access points, he added. With 802.11n, the university could eventually provide IP television, which requires a lot of bandwidth, Murphy said.

Using 802.11n technology, Lapham said he was able to transmit a gigabyte of data in less than two minutes. Currently, the 370-bed medical center has about 450 access points on older protocols. Devices used on the wireless network include 180 laptops, which are used primarily for transmitting bedside patient data. The hospital also supports 100 VoIP wireless phones and a various medical devices.

Wi-Fi is expected to be available in 99 per cent of North American universities by 2013, according to research released by industry analyst ABI Research this week. Much of that penetration will be in the form of 802.11n equipment: higher education is clearly the number one market for early adopters of 802.11n, the company said.

ABI Research expects 802.11n uptake – which is today fairly small in the education market – to ramp up steeply to quite a high rate of penetration," said ABI Research vice president Stan Schatt. There are several reasons for this. ABI said many students now assume a campus Wi-Fi network as a given, and many of their shiny new laptops will be 'n'-compatible. Universities also have great bandwidth demands, as lecture halls may need to serve a large number of users with multimedia contention at any given time and 802.11n's greater speed and capacity can address that need. Moreover, said Schatt, "Universities are breaking new ground by using video over Wi-Fi in a number innovative ways. This is driving the adoption of high speed 802.11n. Students in the near future (at least the diligent ones) will be just as likely to watch their favourite professor's lectures on their laptops as they will be to view 'America's Next Top Model'."

You may also be interested in reading:

Thursday 21 August 2008

Revised paper on “4G” by 3G Americas

3G Americas have published a revised paper on Defining “4G”: Understanding the ITU Process for IMT-Advanced.

3G Americas initially created this white paper one year ago to provide clear understanding regarding the work-in-progress by the ITU, the sole organization responsible for determining the specifications for IMT-Advanced. The current paper updates the considerable progress made by the ITU, establishing a basis for what should be included in an IMT-Advanced system.


While speculation has been going on about 4G technologies, ITU is close to releasing a full set of documentation for this definition. It has held ongoing consultations with the global community over many years on this topic in Working Party 8F under the scope of a work item known as Question ITU-R 229-1/8 “Future development of IMT-2000 and systems beyond IMT-2000.” Following a year-end 2007 restructure in ITU-R, this work is being addressed under the new Study Group 5 umbrella (replacing the former Study Group 8) by Working Party 5D which is the new name for the former WP 8F.

This work in WP 8F, and now WP 5D, has woven together a definition, recipe, and roadmap for the future beyond 3G that is comprised of a balance among a Market and Services View, a Technology View, and a Spectrum View. These, along with Regulatory aspects, are the key elements for business success in wireless.

By mid-2008, ITU-R advanced beyond the vision and framework and developed a set of requirements by which technologies and systems can, in the near future, be determined as a part of IMT- Advanced and in doing so, earn the right to be considered 4G.

During 2008 and though 2009, ITU-R will hold an open call for the “first invitation” of 4G (IMTAdvanced) candidates. Subsequent to the close of the submission period for the “first invitation” an assessment of those candidates' technologies and systems will be conducted under the established ITU-R process, guidelines, and timeframes for this IMT-Advanced ‘first invitation.” The culmination of this open process will be a 4G, or IMT-Advanced family. Such a 4G family, in adherence to the principles defined for acceptance into this process, is globally recognized to be one which can grow to include all aspects of a marketplace that will arrive beyond 2010, thus complementing and building upon an expanding and maturing 3G business.

The paper is available to download from here.

The ITU-R Radiocommunication Bureau has established an “IMT-Advanced” web page (http://www.itu.int/ITU-R/go/rsg5-imt-advanced/) to facilitate the development of proposals and the work of the evaluation groups. The IMT-Advanced web page provides details of the process for the submission of proposals, and will include the RIT and SRIT submissions, evaluation group registration and contact information, evaluation reports and other relevant information on the development of IMTAdvanced.

Monday 18 August 2008

4G: Where are we now.

Last month i read this news about WiMAX leading the world of 4G and last week I read about an American carrier selecting LTE as its choice of 4G technology. Since ITU has decided that they wont be using the term 4G in future and rather use IMT-Advanced or LTE-Advanced, I guess 4G is up for grabs.
The main driver for '4G' is data. Recently carriers have become agressive and started offering some decently priced 'Wireless Broadband' data plans. Rather than confuse people with HSDPA, etc., they have decided to use the term 'Wireless Broadband' or 'Mobile Broadband'. Personally both the terms have managed to confuse some people who associate Mobile Broadband with Internet access on Mobile and Wireless Broadband as broadband on WiFi.

Andrew Seybold makes some valid points in an article in Fierce Wireless. One of the things that he points out is that LTE may tout on higher data rates as compared to others, that is only possble in 20MHz of spectrum. In real world this kind of spectrum is near impossible to obtain. If the spectrum flexibility is removed than HSPA+, LTE, EV-DO Rev B and WiMAX have nearly the same data rates and performance.

For HSPA+ the existing infrastructure can be reused and a software upgrade would suffice whereas for LTE new infrastructure would be required. NTT DoCoMo has fully committed to being the first LTE network operator and others are raising their hands. He thinks that nationwide LTE networks would only be available around 2014.

While I agree with this analysis completely, I think what is going to dictate this transformation from 3G+ to LTE for the operators will be the uptake of data on a network. The biggest advantage of LTE is that it is able to operate in TDD and FDD mode. Operators that have been traditionally using FDD mode of operation will change their loyalty to TDD mode so that they can use asymmetric data transfer. This can provide more capacity in case of some special event taking place (Football finals, Reality show results, etc.) where the users are just interested in receiving information rather than sending any. For operators with paired spectrums, they can use both the band seperately in TDD modes.

Gigaom has list of American operators that are involved in 4G and the list is quite interesting:
  • AT&T: USA's largest network in terms of subscribers, AT&T plans to use LTE to upgrade to 4G, but not for a long, long time. For now it’s content with its current 3G network. It will upgrade to HSPA+ in 2009 and 2010. Eventually it will go to LTE, but won’t begin testing until 2010 or 2011 with full deployment coming after that.
  • Verizon Wireless: Verizon is already testing LTE equipment from several vendors, with plans to roll out the network in 2010 and have most of the country covered by 2012; Verizon’s would likely be the first full U.S. deployment of the LTE technology.
  • Sprint-Nextel: The outlier in the whole transition to 4G, Sprint is going with WiMAX rather than LTE. After a number of delays, the company is set to launch its network in September. By the end of the year it will join with Clearwire to operate a nationwide WiMAX network under the Clearwire brand.
  • T-Mobile: T-Mobile is still launching its 3G coverage, so its 4G networks may take a while to come to fruition. The carrier’s German parent appears to favor LTE.
  • Metro PCS: This budget carrier plans to use LTE but it doesn’t yet have a time frame for deployment, pointing out that its customers aren’t heavy data users yet.
  • U.S. Cellular: The company is unsure of its deployment plans but it would likely choose to follow the rest of the industry with LTE. As for deployment, the time frame isn’t set.
  • Leap Wireless: Recently said it had not made a decision or public comment about its 4G plans.

The picture is a bit different here in UK because all the operators are going to LTE. There may be some ISP's that may be tempted to move to WiMAX as they would get economy of scale. There is also the news of BT (the largest landline phone provider) planning to roll out nationwide WiMAX network in the 2.6GHz spectrum. If BT is able to fulfil its ambition that it could be a big win for the people.

Tuesday 22 April 2008

LTE-Advanced = IMT-Advanced = 4G(or 5G?)

The 3GPP TSG RAN workshop on IMT-Advanced was held (in the week after the RAN WG meetings) on April 7-8, 2008 in Shenzhen, China hosted by ZTE Corporations. The main conclusions from the workshop are:
  • LTE Advanced shall be an evolution of LTE.
    o LTE terminal shall be supported in LTE-advanced networks.
    o An LTE-Advanced terminal can work in an LTE part of the network.
    o Primary focus of LTE-Advanced is low mobility users.
  • All requirements/targets in TR25.913 apply to LTE-Advanced.LTE-Advanced requirements shall fulfill IMT-Advanced requirements within the ITU-R time plan
  • For LTE-Advanced:
    o Same inter-RAT interworking capability with at least same performance as in LTE Release 8
    o Intra-RAT handover performance shall be same or better than LTE Release 8
  • As a way forward for LTE-Advanced it was agreed:
    o TSG RAN email reflector for LTE-Advanced will be established (the new reflector is called 3GPP_TSG_RAN_LTE_ADVANCED and it is available since 21.04.2008)
    § Email discussions on LTE-Advanced requirements will be started on this reflector (moderator: Takehiro Nakamura, NTT DoCoMo, LTE-Advanced SI rapporteur).
    o A new TR will be created (after the workshop it was decided to create TR 36.913 "Requirements for LTE-Advanced") to include LTE-Advanced requirements and updated by RAN WG meetings in May 2008 referring to structure of 25.913 and outcome of the workshop.(note: Allocation of the TR number 36.xyz was done after the workshop.)
    o Review of the outcome of this workshop and kick-off of discussions about LTE-Advanced requirements and technical solutions in RAN WG meetings in May 2008 in Kansas City.The goal is to complete LTE-Advanced requirements at RAN #40 in Prague end of May 2008 according to agreed work plan (i.e. TR 36.913 will be provided to RAN #40).

Monday 3 March 2008

How to sell report using the numbers game



Came across this press release by Research and Markets with title, "4Q07 Global 3G/4G Deployments & Subscribers Tracker ". In this it seems that they have indicated LTE as 4G. LTE standards has not yet been finalised and the technology is not in operation anywhere but this makes the report sound better. Good way of sexing up the report ;)


By the way, if you want to know the bottomline:

3G/4G subscribers (i.e., those subscribers to WCDMA/HSPA, EV-DO, TD-SCDMA, Mobile WiMAX, and LTE networks) grew 91% over the course of 2007, and we expect a 63% growth rate over the course of 2008, with subscribers expected to rise from 230 million in 2007, to 375 million in 2008.

Monday 11 February 2008

Nortel's 4G cocktail at MWC 08

Nortel is busy demo-ing 4G technologies at the Mobile World Congress (MWC ... formerly 3GSM) 2008.

"Today, at home or at the office, your network is just there - putting the world at your fingertips. But if you are out on the move, whether it be for meetings, running errands, or traveling around the world, your communications experience becomes very, very complicated," said Scott Wickware, vice president of marketing and strategy for Carrier Networks, Nortel. "You can e-mail, but you can't send or open certain files. You can surf the net, but you have to wait ages for pages to load and forget about watching a video. Your other option is to search out a WiFi hot spot where you'll then have to pay yet another connection fee. When you go mobile, all of a sudden you are forced to pay attention to the network and you shouldn't have to."
The demand for better connections and the need for the experience to be simple are what drive the next level of innovation in our networks. For wireless networks, that next level of innovation is 4G mobile broadband, which includes LTE and WiMAX. 4G can extend the quality experience that users get from their fixed connections into the mobile world. Nortel has all the elements needed to bring carriers successfully into the 4G world: innovation in WiMAX and LTE, a strong ecosystem, all IP-core, and a deep understanding of what consumer and business users are looking for from their wireless experience.

Nortel's 4G Mobile Broadband website says:
4G delivers true mobile broadband for the masses with a superior user experience. Nortel is boosting the adoption of mobile multimedia and the delivery of a true mobile broadband experience through our leadership in 4G-enabled technologies (WiMAX, LTE (Long Term Evolution), UMB (Ultra Mobile Broadband), and IMS (IP Multimedia Subsystem). 4G mobile broadband provides improved performance, lower total cost of ownership and enables a new era of personalized services. 4G networks are IP-based and flatter with fewer nodes to manage. The benefits are significant and can make 4G mobile broadband a truly disruptive and game-changing technology.
If Nortel calls this 4G then this is 4G ;)

Thursday 13 December 2007

In 4G we trust


So we have this again, LTE is being referred to as 4G. Firstly, this is not really news because i mentioned this in September. Check the post here. Also Verizon is not the first operator to commit to LTE future. AT&T has said the same before them. Regarding the terminology i said earlier that LTE is 3.9G, see here. But 4G sounds better than 3.9G and will confuse ordinary people less so...

Anyway, an article titled "3G bad; 4G better be better" came to my attention:

Not surprisingly, tech-savvy young adults are frustrated by the speed and connectivity limitations of 3G networks and expect both better speed and more reliable connectivity when 4G arrives, according to focus groups in the U.S. and Japan queried by Nortel and the consultant firm CSMG ADVENTIS.

“There was uniform dissatisfaction with today’s UMTS or 3G networks, whether that was because the feeds just weren’t good enough, the applications that they were running, like video, just weren’t good enough.
They look forward in the next generation of technologies to something that can deliver their expectations for these applications in ways that are easy, friendly and useful,” said Scott Wickware, vice president of wireless networks for Nortel.

Wickware said that the focus groups, based in New York City, Seattle and Washington, D.C. in the U.S. and Tokyo and Osaka in Japan, had similar unhappy feelings about their 3G wireless services.

“We expected the Japanese to have a different perspective on this because they’re perceived to be the most tech-savvy nation on the planet, but 25-year-old businesspeople in both countries seem to want the same thing,” Wickware said.

Not coincidentally, what they want is what Nortel has been preaching: “this hyper-trend called mega-connectivity that says everything that could be connected to the network and would be beneficial to the network will be connected to the network,” Wickware said. “We couldn’t have scripted it any better because the feedback came back almost universally saying the same thing.”

The feedback also indicated that users did not necessarily want a single multi-use device but preferred multiple devices connected to the network.
“They don’t want just the mobile phone connected to the network or their PC, they want their camera, their MP3 player, their vehicle, they want everything. I think the trending is a single or dual-purpose device is what a lot of people want,” he said.

Overall, he said, respondents are looking for more from future network services.

“We asked them a wide variety of questions about what they wanted from 4G. We didn’t define 4G for them and lead them down the path to see what they had to say, but left it pretty wide open so we were getting top-of-mind stuff that wasn’t influenced by our views,” he said.

Long time back i remember being so happy with Dial up Internet Connection but now i am not too happy with my 8M broadband. So i suppose the same goes for other technologies.

Monday 27 August 2007

WiMAX on display


Vodafone has deployed WiMAX technology in Malta. The island (population 400,000) is one of Vodafone's smallest markets.

The supplier of the network, Airspan, announced in June that Vodafone Malta had deployed its HiperMAX 80216d 'fixed' WiMAX base stations and CPE to offer bundled mobile, fixed voice, and data services to residential and business customers. Since that announcement was made, Vodafone has joined the lead industry organisation promoting and steering WiMAX development, the WiMAX Forum.

According to Pyramid research, "Vodafone, owing to its scale, is an agent of change in the operator community and we expect others to follow its trajectory. With operators present in different markets and looking for new revenue sources, there is no 'one-size-fits-all' technology, but the wrong technology can set an operator back years."

The research firm adds that "in catering to the needs of different markets and customer segments, operator networks will comprise diverse access technologies, each optimised for certain geographies, demographics, and services. For the WiMAX champions this is good news; for LTE backers it is a strong warning that should lead to increased R&D budgets for the next few years—in both camps.


In other news, Samsung Electronics will demonstrate the next generation telecommunications technologies at its annual international forum, which will shed light on what they call as global 4G technologies and gadgets.

This year’s Samsung 4G Forum will draw more than 130 influential industry leaders and service providers from 26 countries. It will mark the first time that all three candidate 4G technology _ IEEE 802.16m (Mobile WiMAX), 3GPP2 Ultra Mobile Broadband (UMB) and 3GPP Long Term Evolution (LTE) _ will be seen with each other.Each of the 4G technologies has a head cheerleader, with Intel supporting WiMAX, Ericsson touting LTE and Qualcomm preferring UMB. IEEE 802.16m WiMAX, UMB and LTE are expected to be initially implemented in 2010.

I think for companies like Samsung to break into new markets, its very important to use the term 4G. Lets hope that they all succeed.

Saturday 25 August 2007

Is UMB the same as LTE



Recently i have come across press releases trying to sell UMB (Ultra Mobile Broadband) as 4G technology. This is the same as trying to sell LTE and mobile -WiMAX as a 4G technology.

IMT has taken a clever approach and instead of calling the successor of 3G as 4G, they are calling it IMT-Advanced.

The main requirements for 4G are as follows:

  • Peak data rate of 100Mbps for high mobility applications such as mobile access
  • Approx. 1Gbps for low mobility applications such as nomadic/local wireless access

Doing some digging on the UMB topic, i realised that it is the same as LTE but an evolution from CDMA2000. This is being standardised by 3GPP2.

Some of the key features (and comparing it with LTE) includes:

  • It used OFDMA based air interface (same as LTE)
  • It supports FDD (LTE supports FDD and TDD and a combination of them so i am not sure if UMB only supports FDD)
  • Scalable b/w of 1.25MHz to 20MHz (same as LTE)
  • MIMO and Beamforming (Same as LTE but UMB also supports 4x4 antennas whereas LTE supports 2x2)
  • Data speeds upto 275Mbps in DL and 75Mbps in UL (LTE has 144Mbps in DL and 57Mbps in UL but that is because of 2x2 MIMO)

Since the term 4G is already being abused so much, one option is to let people use 4G as they wish and then when IMT-Advanced is available, start calling it 5G. What do you think?

Tuesday 21 August 2007

Prepare for WiMAX 2.0



I was completely unaware of IEEE 802.16m which is promising speeds upto 1Gbps. Only when someone asked me what my opinion was on this i did some digging in this.


IEEE 802.16m promises to deliver speeds up to 1Gbps and be backward compatible with 802.16e-2005 (mobile WiMAX) solutions. The 802.16m group should wrap up the technology development phase in 2007. Similar to existing mobile WiMAX, 802.16m will use multiple-input/multiple-output (MIMO) antenna technology. The idea with 802.16m, though, is to increase bandwidth by using larger MIMO antenna arrays.


The 802.1m group is targeting ratification and finalization of the standard by late 2009. So, we’re still a couple of years (or more) from having a gigabit version of WiMAX. As compared to other IEEE 802 standards development, such as 802.11, this is an aggressive schedule. In my opinion, these will be difficult dates to hit, especially with the requirement for being backward compatible with 802.16e-2005.


The advantage of 802.11m to cellular companies is that it could allow the convergence of 3G and 802.16 into a single 4G technology for mobile and fixed applications. This would enable cellular companies to offer service, such as IPTV and VoIP, as effectively over wireless connections as they are today on wired networks. This would lead to competition with existing fixed wireless broadband services currently delivered over cable and telephone lines.


Many vendor sources however, have expressed some skepticism about the speed with the work can be completed (the end of 2009 is being mooted as a baked date) and the chances of maintaining backwards compatibility with mobile 802.16 technology. Some folks worry that carriers have unrealistic expectations on how fast new WiMax profiles and interfaces can be developed. "They just walk in, snap their fingers, and expect it to happen," one industry source told us on the show floor yesterday. After all, it took several years for the IEEE to arrive at a satisfactory fixed broadband wireless specification in the form of 802.16d and even longer for the WiMAX Forum to certify interoperability between products using the technology.


Martin has some interesting analysis on his Mobile technology page:


Between today and WiMAX II, there's systems such as WiMAX and LTE which promise faster data rates than those available today by mainly doing the following:
  • Increase the channel bandwidth: HSDPA uses a 5 MHz channel today. WiMAX and LTE have flexible channel bandwidths from 1.25 to 20 MHz (Note: The fastest WiMAX profile currently only uses a 10 MHz channel today for the simple reason that 20 MHz of spectrum is hard to come by). So by using a channel that is four times as broad as today, data rates can be increased four times.
  • Multiple Input, Multiple Output (MIMO): Here, multiple antennas at both the transmitting and receiving end are used to send independent data streams over each antenna. This is possible as signals bounce of buildings, trees and other obstacles and thus form independent data paths. Both LTE and WiMAX currently foresee 2 transmitting and 2 receiving antennas (2x2 Mimo). In the best case this doubles data rates.
  • Higher Order Modulation: While HSDPA uses 16QAM modulation that packs 4 bits into a single transmission step, WiMAX and LTE will use 64QAM modulation under ideal transmission conditions which packs 6 bits into a single transmission step.
By using the techniques above, LTE and WIMAX will be able to increase today's 2 MBit/s to about 20-25 MBit/s. That's still far away from the envisaged 1.000 GBit/s. To see how to get there let's take a look at what NTT DoCoMo is doing in their research labs, as they have already achieved 5 GBit/s on the air interface and have been a bit more open at what they are doing (see

here and especially here):
  • Again increase of the channel bandwidth: They use a 100 MHz channel for their system. That's 4 times wider than the biggest channel bandwidth foreseen for LTE and 20 times wider than used for today's HSDPA. Note that in practice it might be quite difficult to find such large channels in the already congested radio bands.
  • 12x12 MIMO: Instead of 2 transmit and receive antennas, DoCoMo uses 12 for their experiments. Current designers of mobile devices already have a lot of trouble finding space for 2 antennas so a 12x12 system should be a bit tricky to put into small devices.
  • A new modulation scheme: VSF spread OFDM. This one's a bit mind bogelling using CDMA and OFDM in combination. Wikipedia contains a description of something called VSF-OFCDM which might be a close brother.


More Information available at IEEE 802.16 Task Group m (TGm) page.

Tuesday 24 July 2007

China trying to catch up on 4G


In a move to improve the nation's research and development (R&D) capability, top mobile phone operator China Mobile will promote more self-developed next-generation mobile network technologies that match international standards, an official at its research institute disclosed.

The Research Institute of China Mobile has started several projects for the next generation of mobile network technology.

Wireless internet protocol on internet service environment (WIISE), a technology designed to let mobile networks better manage their bandwidth capacity, is among the institute's key research projects. It is funded by the State.

"We do want to do more on this WIISE technology in the next two years with our proprietary intellectual property rights. We do also want to push this self-developed technology internationally," said Wang Xiaoyun, a deputy manager of the institute yesterday.

Ms Wang explained that the WIISE technology is not designed for present mobile technology but will be applicable to so-called 4G technology or technology even more advanced. "We do want to increase the network management power, which could lead to better use of our network resources," she said.
The Chinese government, in the form of its Ministry of Science and Technology, is also reported to be collaborating with its Swedish counterpart, in the form of the VINNOVA agency for innovation, in a 4G research project initially funded at nearly US$8mn. Public details of that collaboration are minimal (that is, none at this juncture).

China Mobile will host a conference jointly with the government later this year to discuss the issue of advanced technology.

The 4G mobile technology is expected to be in the market by 2010, with Japanese mobile operator NTT DoCoMo having taken the lead in its development. The 4G systems are expected to be able to handle a wide range of data-supported rates of up to about 100 megabits per second for high mobility networks.

China Mobile would like to strengthen its network management system in the next-generation network as demand for bandwidth is increasing.
"The new mobile technology will be more compatible with the use of the internet on the move, whereas the existing 3G technologies still have some weakness with internet applications," Ms Wang said.
Some internet-based applications that occupy a lot of network capacity, such as the peer-to-peer (P2P) network, will be migrated to the mobile network in the future, she said.

As the world's largest mobile operator, China Mobile is bent on developing technology to enhance the mobile internet experience with a cost advantage.
Source: China Daily

Thursday 19 July 2007

Defining 4G (I mean IMT-Advanced)

3G Americas published a new white paper entitled "Defining 4G: Understanding the ITU Process for the Next Generation of Wireless Technology". The white paper provides the factual description of how IMT-Advanced or 4G will someday be defined by the International Telecommunications Union (ITU). ITU is the internationally recognized authority that will produce the official definition of the next generation of wireless technologies beyond IMT-2000 or 3G.

Chris Pearson, President of 3G Americas, stated, "The ITU is currently establishing criteria for IMT-Advanced and will be screening various technologies for inclusion in the IMT-Advanced family. Only then will we understand what is and can be rightly and credibly called 4G.” He continued, "Any claim today that a particular technology is a so-called ‘4G technology’, in reality, is simply a marketing spin, creating market confusion and deflating the importance of the telecommunications industry standards. Technologies should be verified against a set of agreed-upon requirements in order to qualify as 4G, and this will happen in the future when the requirements are outlined by the ITU."

Significant progress has been made by the Radiocommunication Sector of the ITU (ITU-R) in establishing an agreed and globally accepted definition of 4G wireless systems, and ITU-R is close to releasing a full set of documentation for this definition. Working under a mandate to address systems beyond 3G, ITU-R has progressed from delivering a vision of 4G in 2002 to establishing a name for 4G in 2005 (IMT-Advanced). In 2006, ITU-R set out the principles for the process of the development of IMT-Advanced. The work of the ITU encompasses the important elements of business success in the wireless industry, especially the balance of a market and services view, a technology view, a spectrum view and regulatory aspects. In early 2008, ITU-R will translate the vision into a set of requirements by which technologies and systems can, in the near future, be determined a part of IMT-Advanced and in doing so, earn the credible right to be considered 4G.

During 2008 and 2009, ITU-R will hold an open call for 4G (IMT-Advanced) candidates as well as an assessment of those candidates' technologies and systems. The culmination of this open process will be a 4G, or IMT-Advanced family of technologies. Such a 4G family of technologies, in adherence to the principles defined for acceptance into this ITU process, is globally recognized to be one which can grow to include all aspects of a marketplace that will arrive beyond 2010.

“Third generation technologies are growing immensely in the marketplace, but they too once started out with a vision and requirements from ITU,” stated Pearson. “The evolving wireless marketplace and its customers will be well served by the current ITU process for the next generation of wireless services.”



As can be seen in the picture above, the main requirements for 4G are as follows:
  • Peak data rate of 100Mbps for high mobility applications such as mobile access
  • Approx. 1Gbps for low mobility applications such as nomadic/local wireless access
A very important point in the report is what i have been saying for years:

The communications industry is witnessing significant posturing about wireless technologies and systems that are claiming to be “4G.” Any claim that a particular technology is a 4G technology or system today is, in reality, simply
a market positioning statement by the respective technology advocate. Such claims must be verified and substantiated against a set of requirements in order to qualify as 4G.

Monday 16 July 2007

300 Mbps with 'Super-FOMA'


NTT DoCoMo, Inc. announced that this month it began testing an experimental Super 3G system for mobile communications. With this experiment, DoCoMo will seek to achieve a downlink transmission rate of 300Mbps over a high-speed wireless network.
For people who are unaware, LTE is being branded as Super-3G as this term is more appealing as compared to LTE which would mean nothing to ordinary people.
DoCoMo will begin with an indoor experiment to test transmission speed using one transmitting and one receiving antenna. The company will then expand the experiment to examine downlink transmission by employing up to four Multiple-Input Multiple-Output (MIMO) antennas for both the base station (transmission side) and mobile station (receiving side); the goal is to achieve a downlink transmission speed of 300Mbps. MIMO is an antenna technology for wireless communications in which different data streams are spatially multiplexed using multiple antennas for both transmission and reception on the same frequency. Also to be examined is the "handover function" — switching of the connection between two base stations.
NTT DoCoMo's Super-3G timetable is available here
The reason i am calling this setup as Super-FOMA is because going back to when 3G was being introduced, DoCoMo wanted to be the first with 3G. As a result, they adopted a 3GPP Release version that wasnt stable and released it as FOMA. Now they are doing the same with LTE. LTE wont be stable in that timeframe so they might end up with Super-FOMA instead of Super-3G.
The company has also been aggressively pursuing 4G system development. In late December, the carrier came close to hitting a 5Gbit/sec. data transmission speed from an experimental 4G system to a receiver moving at 10 kilometers per hour.
Possibly it may be the first one with a 4G system and it might end up as Hyper-FOMA :)