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Showing posts with label Spectrum. Show all posts
Showing posts with label Spectrum. Show all posts

Friday, 21 November 2014

In-flight broadband connectivity service with speeds up to 75Mbps


Came across the following Inmarsat press release:

The new network represents two world-beating achievements for Inmarsat and its partners. It will be the world’s first truly hybrid aviation network, consisting of an S-band satellite (Europasat), constructed by Thales Alenia Space, and a Europe-wide S-band ground network. Over the integrated network, based on state-of-the-art LTE technology and access to sufficient spectrum resources, Inmarsat will be offering airlines the world’s fastest in-flight broadband connectivity service with speeds up to 75Mbps, far in excess of the limited capabilities of North American ATG systems.
Alcatel-Lucent and Inmarsat will work together to develop the ground infrastructure component of the new Europe-wide network. Alcatel-Lucent has proven expertise in the development of 4G LTE-based air-to-ground technology and was the world’s first company to field trial this technology in 2011. The initial contract awarded to Alcatel-Lucent will see the global telecommunications equipment company adapting their existing 4G LTE technology to support the S-band spectrum.
Recently Christophe WILHELM, Senior VP Strategy & Innovation, Thales Alenia Space gave a presentation in the Digiworld Summit 2014.



His presentation is above and the video is as follows. Please forward to 1:36:00 to watch his part



Tuesday, 11 November 2014

New Spectrum Usage Paradigms for 5G

Sometime back I wrote a post that talked about Dynamic Spectrum Access (DSA) techniques for Small Cells and WiFi to work together in a fair way. The Small Cells would be using the ISM bands and Wi-Fi AP's would also be contending for the same spectrum. For those who may not know, this is commonly referred to as LTE-U but the correct term that is being used in standards is LA-LTE, see here for details.

IEEE Comsoc has just published a whitepaper that details how the spectrum should be handled in 5G to make sure of efficient utilisation. The whitepaper covers the following:

Chapter 2 – Introduction, the traditional approach of repurposing spectrum and allocating it to Cellular Wireless systems is reaching its limits, at least below the 6GHz threshold. For this reason, novel approaches are required which are detailed in the sequel of this White Paper.

Chapter 3 - Spectrum Scarcity - an Alternate View provides a generic view on the spectrum scarcity issue and discusses key technologies which may help to alleviate the problem, including Dynamic Spectrum Management, Cognitive Radios, Cognitive Networks, Relaying, etc. 

Chapter 4 – mmWave Communications in 5G addresses a first key solution. While spectrum opportunities are running out at below 6 GHz, an abundance of spectrum is available in mmWave bands and the related technology is becoming mature. This chapter addresses in particular the heterogeneous approach in which legacy wireless systems are operated jointly with mmWave systems which allows to combine the advantages of both technologies. 

Chapter 5 – Dynamic Spectrum Access and Cognitive Radio: A Current Snapshot gives a detailed overview on state-of-the-art dynamic spectrum sharing technology and related standards activities. The approach is indeed complementary to the upper mmWave approach, the idea focuses on identifying unused spectrum in time, space and frequency. This technology is expected to substantially improve the usage efficiency of spectrum, in particular below the 6GHz range. 

Chapter 6 – Licensed Shared Access (LSA) enables coordinated sharing of spectrum for a given time period, a given geographic area and a given spectrum band under a license agreement. In contract to sporadic usage of spectrum on a secondary basis, the LSA approach will guarantee Quality-of-Service levels to both Incumbents and Spectrum Licensees. Also, a clear business model is available through a straightforward license transfer from relevant incumbents to licensees operating a Cellular Wireless network in the concerned frequency bands. 

Chapter 7 – Radio Environment Map details a technology which allows to gather the relevant (radio) context information which feed related decision making engines in the Network Infrastructure and/or Mobile Equipment. Indeed, tools for acquiring context information is critical for next generation Wireless Communication systems, since they are expected to be highly versatile and to constantly adapt. 

Chapter 8 – D2DWRAN: A 5G Network Proposal based on IEEE 802.22 and TVWS discusses the efficient exploitation of TV White Space spectrum bands building on the available IEEE 802.22 standard. TV White Spaces are indeed located in highly appealing spectrum bands below 1 GHz with propagation characteristics that are perfectly suited to the need of Wireless Communication systems. 

Chapter 9 – Conclusion presents some final thoughts. 

The paper is embedded as follows:



Sunday, 19 October 2014

What is (pre-5G) 4.5G?

Before we look at what 4.5G is, lets look at what is not 4.5G. First and foremost, Carrier Aggregation is not 4.5G. Its the foundation for real 4G. I keep on showing this picture on Twitter


I am sure some people much be really bored by this picture of mine that I keep showing. LTE, rightly referred to as 3.9G or pre-4G by the South Korean and Japanese operators was the foundation of 'Real' 4G, a.k.a. LTE-Advanced. So who has been referring to LTE-A as 4.5G (and even 5G). Here you go:


So lets look at what 4.5G is.
Back in June, we published a whitepaper where we referred to 4.5G as LTE and WiFi working together. When we refer to LTE, it refers to LTE-A as well. The standards in Release-12 allow simultaneous use of LTE(-A) and WiFi with selected streams on WiFi and others on cellular.


Some people dont realise how much spectrum is available as part of 5GHz, hopefully the above picture will give an idea. This is exactly what has tempted the cellular community to come up with LTE-U (a.k.a LA-LTE, LAA)

In a recent event in London called 5G Huddle, Alcatel-Lucent presented their views on what 4.5G would mean. If you look at the slide above, it is quite a detailed view of what this intermediate step before 5G would be. Some tweets related to this discussion from 5G Huddle as follows:

Finally, in a recent GSMA event, Huawei used the term 4.5G to set out their vision and also propose a time-frame as follows:



While in Alcatel-Lucent slide, I could visualise 4.5G as our vision of LTE(-A) + WiFi + some more stuff, I am finding it difficult to visualise all the changes being proposed by Huawei. How are we going to see the peak rate of 10Gbps for example?

I have to mention that I have had companies that have told me that their vision of 5G is M2M and D2D so Huawei is is not very far from reality here.

We should keep in mind that this 4G, 4.5G and 5G are the terms we use to make the end users aware of what new cellular technology could do for them. Most of these people understand simple terms like speeds and latency. We may want to be careful what we tell them as we do not want to make things confusing, complicated and make false promises and not deliver on them. 

Saturday, 9 August 2014

Multi-Frequency Band Indicator (MFBI)

I am sure we all know that LTE bands have been growing, every few months. All the 32 bands for FDD have now been defined. The 33rd band is where TDD bands start. What if we now want to have more FDD bands? Well, we will have to wait to fix that problem.

Picture Source: LG Space

Anyway, as can be seen in the above picture, some of the frequency bands overlap with each other. Now you may have a UE thats camped onto one frequency that is overlapping in different bands. Wouldn't it be useful to let the UE know that you are camped in more than one band and you can change it to another frequency which may be a different band but you were already on it in the first place (it may sound confusing).

Here is a much simpler table from the specs that show that when a UE is camped on band 5, it may also be camped on bands 18, 19 and 26. Remember the complete bands may not be overlapping but may only be partially overlapping.

An example could be Sprint that used Band 38 TDD (BW 50MHz) for its legacy devices but is now able to use Band 41 (BW 194MHz) as well. The legacy devices may not work on Band 41 but the new devices can use much wider band 41. So the transmission would still say Band 38 but the new devices can be informed of Band 41 using the System Information Block Type 1. AT&T has a similar problem with Band 12 and 17.

Even though this was implemented in Release-8, it came as a part of Late Non-critical extensions. Its a release independent feature but not all UE's and Network have implemented it. The UE indicates the support for MFBI using the FGI (Feature Group Indicator) bits. 

Sunday, 20 July 2014

LA-LTE and LAA


Recently came across a presentation by Ericsson where they used the term LA-LTE. I asked a few colleagues if they knew or could guess what it means and they all drew blank. I have been blogging about Unlicensed LTE (a.k.a. LTE-U) on the Small Cells blog here. This is a re-branding of LTE-U

LA-LTE stands for 'Licensed Access' LTE. In fact the term that has now been adopted in a recent 3GPP workshop (details below) is Licensed Assisted Access (LAA).

Couple of months back I blogged in detail about LTE-U here. Since then, 3GPP held a workshop where some of the things I mentioned got officially discussed. In case you want to know more, details here. I have to mention that the operator community is quite split on whether this is a better approach or aggregating Wi-Fi with cellular a better approach.

The Wi-Fi community on the other hand is unhappy with this approach. If cellular operators start using their spectrum than it means less spectrum for them to use. I wrote a post on the usage of Dynamic Spectrum Access (DSA) Techniques that would be used in such cases to make sure that Wi-Fi and cellular usage does not happen at the same time, leading to interference.

Here is a presentation from the LTE-U workshop on Use cases and scenarios, not very detailed though.



Finally, the summary presentation of the workshop. As it says on the final slide "The current SI proposal focuses on carrier aggregation operations and uses the acronym LAA (Licensed Assisted Access)", you would be seeing more of LAA.


Friday, 4 July 2014

Cell capacity and Opportunistic Use of Unlicensed and Shared Spectrum

One very interesting presentation from the LTE World Summit was about Improving the cell capacity by using unlicensed and shared spectrum opportunistically. Kamran Etemad is a senior advisor to FCC & UCMP and even though he was presenting this in his personal capacity, it reflected some interesting views that are quite prevalent in the USA.

If you don't know about Dynamic Spectrum Access Schemes, I wrote a post on the Small Cells blog here. The slide above is quite interesting as it shows the possibility of a 'Generalized' Carrier Aggregation in 3GPP Release-13. Personally, we believe that LTE + WiFi working together will be far more successful than LTE + LTE-U (unlicensed). As the blog readers would be aware, we have been pushing our vision of LTE + Wi-Fi working together; which we are calling as 4.5G. In case if you have not seen, our whitepaper is here.

The presentation is embedded below for reference:


Wednesday, 2 July 2014

Case Study: Migrating from WiMAX to TD-LTE



I was glad to hear this case study by Mike Stacey where they have a WiMAX network already deployed and are in process of moving to TD-LTE. Along with the technical issues there are also business and customer issues that need to be taken into account while doing this technology swap. Surprisingly 3.5GHz is also not a very popular band because there are very few deployments in this spectrum. On the other hand, most of the companies worldwide that have been able to get their hands on this spectrum, generally got a big chunk (60-100MHz) so they would be able to do CA easily (bar the technical issues of Intra-band interference).

Anyway, the presentation is embedded below. Hope you find it useful. If you know of similar experiences, please feel free to add them in the comments.


Wednesday, 21 May 2014

Connected and Autonomous Car Revolution

Last week we had the Automotive and Transport SIG event in Cambridge Wireless. There is already some good writeup on that event here and here. In this post my interest in looking at the technologies discussed.

R&S (who were the sponsors) gave their introduction presentation quite well highlighting the need and approaches for the connected car. He also introduced the IEEE 802.11p to the group.

As per Wikipedia, "IEEE 802.11p is an approved amendment to the IEEE 802.11 standard to add wireless access in vehicular environments (WAVE), a vehicular communication system. It defines enhancements to 802.11 (the basis of products marketed as Wi-Fi) required to support Intelligent Transportation Systems (ITS) applications. This includes data exchange between high-speed vehicles and between the vehicles and the roadside infrastructure in the licensed ITS band of 5.9 GHz (5.85-5.925 GHz). IEEE 1609 is a higher layer standard based on the IEEE 802.11p."

Back in December, Dr. Paul Martin did an equally useful presentation in the Mobile Broadband SIG and his presentation is equally relevant here as he introduced the different terms live V2X, V2i, V2V, V2P, etc. I have embedded his presentation below:



Roger Lanctot from Strategy Analytics, gave us some interesting facts and figures. Being based in the US, he was able to give us the view of both US as well as Europe. According to him, “LTE is the greatest source of change in value proposition and user experience for the customer and car maker. Bluetooth, Wi-Fi, NFC and satellite connectivity are all playing a role, but LTE deployment is the biggest wave sweeping the connected car, creating opportunities for new technologies and applications.” His officially released presentation is embedded below (which is much smaller than his presentation on that day.



There were also interesting presentations that I have not embedded but other may find useful. One was from Mike Short, VP of Telefonica and the other was from Dr. Ireri Ibarra of MIRA.


The final presentation by Martin Green of Visteon highlighted some interesting discussions regarding handovers that may be required when the vehicle (and the passengers inside) is moving between different access networks. I for one believe that this will not be an issue as there may be ways to work the priorities of access networks out. Anyway, his presentation included some useful nuggets and its embedded below:


Monday, 3 February 2014

5G and the ‘Millimeter-Wave' Radios


There were quite a few interesting talks in the Cambridge Wireless Radio Technology SIG event last week. The ones that caught my attention and I want to highlight here are as follows.

The mobile operator EE and 5GIC centre explained the challenges faced during the Practical deployments. Of particular interest was the considerations during deployments. The outdoor environments can change in no time with things like foliage, signage or even during certain festivals. This can impact the radio path and may knock out certain small cells or backhaul. The presentation is available to view and download here.


Another interesting presentation was from Bluwireless on the 60GHz for backhaul. The slide that was really shocking was the impact of regulation in the US and the EU. This regulation difference means that a backhaul link could be expensive and impractical in certain scenarios in the EU while similar deployments in the US would be considerably cheaper. This presentation is available here.


Finally, the presentation from Samsung highlighted their vision and showed the test results of their mmWave prototype. The presentation is embedded below and is available here.



Finally, our 5G presentation summarising our opinion and what 5G may contain is available here. Dont forget to see the interesting discussion in the comments area.

Monday, 3 June 2013

New Carrier Type (NCT) in Release-12 and Band 29

One of the changes being worked on and is already available in Release-11 is the Band 29. Band 29 is a special FDD band which only has a downlink component and no uplink component. The intention is that this band is available an an SCell (Secondary cell) in CA (Carrier Aggregation). 

What this means is that if this is only available as an SCell, any UE that is pre-Rel-11 should not try to use this band. It should not read the system information, reference information, etc. In fact the System Information serves little or no purpose as in CA, the PCell will provide the necessary information for this SCell when adding it using the RRC Reconfiguration message. This gives rise to what 3GPP terms as New Carrier Type for LTE as defined here. An IEEE paper published not long back is embedded below that also describes this feature in detail. 

The main thing to note from the IEEE paper is what they have shown as the unnecessary information being removed to make the carrier lean.

China Mobile, in their Rel-12 workshop presentation, have suggested 3 different types/possibilities for the NCT for what they call as LTE-Hi (Hi = Hotspot and Indoor).

Ericsson, in their Rel-12 whitepaper mention the following with regards to NCT:

Network energy efficiency is to a large extent an implementation issue. However, specific features of the LTE technical specifications may improve energy efficiency. This is especially true for higher-power macro sites, where a substantial part of the energy consumption of the cell site is directly or indirectly caused by the power amplifier.

The energy consumption of the power amplifiers currently available is far from proportional to the power-amplifier output power. On the contrary, the power amplifier consumes a non-negligible amount of energy even at low output power, for example when only limited control signaling is being transmitted within an “empty” cell.

Minimizing the transmission activity of such “always-on” signals is essential, as it allows base stations to turn off transmission circuitry when there is no data to transmit. Eliminating unnecessary transmissions also reduces interference, leading to improved data rates at low to medium load in both homogeneous as well as heterogeneous deployments.

A new carrier type is considered for Release 12 to address these issues. Part of the design has already taken place within 3GPP, with transmission of cell-specific reference signals being removed in four out of five sub frames. Network energy consumption can be further improved by enhancements to idle-mode support.

The IEEE paper I mentioned above is as follows:



Saturday, 23 March 2013

LTE for Public Safety Networks

The last presentation on this topic couple of months back has reached nearly 7K views so here is another one from a recent article on the same topic from IEEE Communications Magazine



Thursday, 14 February 2013

Scalable UMTS (S-UMTS) to accelerate GSM Refarming


Looks like a good idea from LTE will possibly be applied to UMTS/HSPA and it will also help accelerate the re-farming of GSM spectrum. A recent presentation from Qualcomm below:



Available to download from here.

Saturday, 15 December 2012

Spectrum auction results from The Netherlands



The result of the auction: 

8009001800210019002600
KPN2x102x102x202x5
 30
Vodafone2x102x102x202x5

T-Mobile
2x152x30
4,9+9,7 25
 Tele22x10




The total price of the auction:
  • Vodafone 1,380,800,000 euro (1.381 billion)
  • KPN 1,351,852,000 euros (1.352 billion)
  • T-Mobile 910,681,000 euro (910.8 million)
  • Tele2 euro 160,813,000 (160.8 million)
After the auction is the distribution of the main bands is as follows:
 800900 no  900 new 1800 no 1800 new 2100 no 2100 new 2600
 KPN2x10  2x12,4 2x10 2x18,4 2x20 2x15 2x20 2x10
 Vodafone2x10 2x12,4 2x10 2x4,8 2x20 2x15 2x20 2x10
 T-Mobile 2x10 2x15 2x30,6 2x30 2x20 2x20 2x5
 Tele22x10 - - - - - - 2x20
 TO - - - - - 2x20

Sources:

LTE Rollouts planned:
Vodafone - Summer 2013
KPN - February 2013

Added 15/12/12:11.48

You can also see it visually as in the slide below:




Wednesday, 12 September 2012

UK: Spectrum, Operators, Vendors and LTE

So LTE (or '4G') is about to be launched in the UK as announced yesterday. Its going to be branded as 4GEE.

Here is a summary of the Spectrum in the UK that will be used for LTE and would be auctioned by Ofcom.


Here is the current allocation of Spectrum in the UK

The above pics are from a presentation by Ofcom in LTE World Summit 2012 in Barcelona, available here.



The last table is from an Ofcom document here. Its very interesting read. For example I didnt know that The L-band was the first major part of Ofcom spectrum awards programme relevant to mobile services. It consists of 40MHz between 1452MHz and 1492MHz. The auction took place in May 2008, in which Qualcomm won the entirety of the available spectrum.

Here is the summary of the operators working on LTE:


Everything Everywhere (EE = Orange + T-Mobile) - They are calling their '4G' service as EE, covering up to 70% of the UK by the end of 2013. Network kit provided by Huawei.

Three - Samsung will provide the Radio Access Network, and the core infrastructure, for Three's LTE (4G) network. That includes the base stations, and radio core. 3 UK has agreed to purchase 2 x 15 MHz of 1800 MHz spectrum from Everything everywhere, and plans commercial launch of LTE service in 2013.

Telefonica (O2) trial network - Equipment supplied by Nokia Siemens Networks (NSN) for both the Radio and Core network elements. Backhaul for the 4G trial network has been provided using Microwave Radio Equipment from Cambridge Broadband Networks Limited, NEC and Nokia Siemens Networks.

Updated 13/09/12 - 11:25

UK Broadband rolled out the first commercial TD-LTE network in London back in February (available to customers since May 2012). The equipment is provided by Huawei. They have 40MHz in Band 42 (3.5GHz) and 84MHz in band 43 (3.6GHz).

Vodafone - No news.


Anything else I missed?

Tuesday, 11 September 2012

New Carrier-Aggregation Proposed Bands

Carrier Aggregation (CA) the promised feature of LTE-A that will make it compatible to IMT-A is not fully exploited in Rel-10. There are only 2 bands supported for CA in Rel-10 and the same for Rel-11. The following are the bands for Rel-10

And the following for Rel-11

Unfortunately these are not enough for all the operators launching LTE/LTE-A. As a result there is currently a study on lots of other bands ongoing within 3GPP. Here is my understanding of the bands that would be needed and the region where they would be needed. Interested in knowing if there are other operators/regions where other bands need to be included.
 

Wednesday, 5 September 2012

Qualcomm's 1000x Challenge

Qualcomm has been promoting the '1000x' challenge and has recently held a webinar to make everyone aware of how 1000 times efficiency may be achieved. I think there is always a scope of achieving a better efficiency but putting a figure may not necessarily give the desired results. Anyway, here are the slides.



You can listen to the webinar here. The promotional video is available here.

A writeup on this topic by Steven Crowley is available here.

Tuesday, 8 May 2012

WiFi: Standards, Spectrum and Deployment

Yesterday, IEEE published its fourth revision to 802.11. The updates include faster throughput, improved cellular hand-offs, and better communication between vehicles in addition to other improvements.The following from IEEE website:

The new IEEE 802.11-2012 revision1 has been expanded significantly by supporting devices and networks that are faster, more secure, while offering improved Quality of Service and, improved cellular network hand-off. IEEE 802.11 standards, often referred to as “Wi-Fi®,” already underpin wireless networking applications around the world, such as wireless access to the Internet from offices, homes, airports, hotels, restaurants, trains and aircraft around the world. The standard’s relevance continues to expand with the emergence of new applications, such as the smart grid, which augments the facility for electricity generation, distribution, delivery and consumption with a two-way, end-to-end network for communications and control.

IEEE 802.11 defines one MAC and several PHY specifications for wireless connectivity for fixed, portable and mobile stations. IEEE 802.11-2012 is the fourth revision of the standard to be released since its initial publication in 1997. In addition to incorporating various technical updates and enhancements, IEEE 802.11-2012 consolidates 10 amendments to the base standard that were approved since IEEE 802.11’s last full revision, in 2007. IEEE 802.11n™, for example, defined MAC and PHY modifications to enable much higher throughputs, with a maximum of 600Mb/s; other amendments that have been incorporated into IEEE 802.11-2012 addressed direct-link setup, “fast roam,” radio resource measurement, operation in the 3650-3700MHz band, vehicular environments, mesh networking, security, broadcast/multicast and unicast data delivery, interworking with external networks and network management.

“The new IEEE 802.11 release is the product of an evolutionary process that has played out over five years and drawn on the expertise and efforts of hundreds of participants worldwide. More than 300 voters from a sweeping cross-section of global industry contributed to the new standard, which has roughly doubled in size since its last published revision,” said Bruce Kraemer, chair of the IEEE 802.11 working group. “Every day, about two million products that contain IEEE 802.11-based technology for wireless communications are shipped around the world. Continuous enhancement of the standard has helped drive technical innovation and global market growth. And work on the next generation of IEEE 802.11 already has commenced with a variety of project goals including extensions that will increase the data rate by a factor of 10, improve audio/video delivery, increase range and decrease power consumption.”

1 IEEE 802.11™-2012 “Standard for Information technology--Telecommunications and information exchange between systems Local and metropolitan area networks--Specific requirements Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications”


The following is from a presentation by Agilent in LTE World Summit last year. It summarises the 802.11 standards, the Spectrum available and deployment use cases.