MCPTT Off-network and UE to UE/Network Relays

3GPP SA6 recently held a workshop on Mission Critical Push To Talk (MCPTT) stage 3 development in Canada. You can look at the meeting report here and download any presentations from here.

An interesting presentation that caught my attention was one on "MCPTT Off-network Architecture". The presentation is embedded below where it is described technically what is meant by Off-network. From my understanding an off-network from MCPTT point of view is one where the UE does not have network coverage.

In such a situation a UE can connect to another UE that can connect to UE/network (if available) to relay the message. Its similar to another technology that I have talked about, Multihop Cellular Networks and ODMA. Anyway, here is the presentation:

Sometimes the standards can take too long to develop a feature and apps can come and deliver a similar service at a very short notice. One such App that does something similar is called Firechat, which played a big role in many protests worldwide. The video explaining it below is worth watching.


The problem with Apps is that they cannot be used by the emergency services or other governmental organisations, unless a standard feature is available. This is the expectation from this Off-network relays. It would work in combination with D2D/ProSe.


For anyone interested in the latest Public Safety (PS), here is a presentation by SA6 chairman from July

New LTE UE Categories: 11, 12, 13 and 14 in 3GPP Rel-12

While checking 3GPP TS 36.306, I noticed some new LTE categories have been defined. We now have all the way up to category 14. I also noticed that Wikipedia page has up to Category 15, not sure how/where they got it from. 

The LG Space page has some more details for anyone interested in exploring further.

A Qualcomm demo from MWC for LTE Category 11, if interested.



Finally, other related posts:

• LTE Category-0 low power M2M devices 
• New LTE-A UE Category 9 and 10 in Rel-11
• LTE-Advanced (Rel-10) UE Categories
• 1200Mbps DL with LTE-Advanced

LTE-Hetnet (LTE-H) a.k.a. LTE Wi-Fi Link Aggregation (LWA)

We have talked about the unlicensed LTE (LTE-U), re-branded as LTE-LAA many times on this blog and the 3G4G Small Cells blog. In fact some analysts have decided to call the current Rel-12 non-standardised Rel-12 version as LTE-U and the standardised version that would be available as part of Release-13 as LTE-LAA.

There is a lot of unease in the WiFi camp because LTE-LAA may hog the 5GHz spectrum that is available as license-exempt for use of Wi-Fi and other similar (future) technologies. Even though LAA may be more efficient as claimed by some vendors, it would reduce the usage for WiFi users in that particular spectrum.

As a result, some vendors have recently proposed LTE/WiFi Link Aggregation as a new feature in Release-13. Alcatel-Lucent, Ruckus Wireless and Qualcomm have all been promoting this. In fact Qualcomm has a pre-MWC teaser video on Youtube. The demo video is embedded as follows:



The Korean operator KT was also involved in demoing this in MWC along with Samsung and Qualcomm. They have termed this feature as LTE-Hetnet or LTE-H.

The Korean analyst firm Netmanias have more detailed technical info on this topic.

Link aggregation by LTE-H demonstrated at MWC 2015 (Source: Netmanias)

As can be seen the data is split/combined in PDCP layer. While this example above shows the practical implementation using C-RAN with Remote Radio Head (RRH) and BaseBand Unit (BBU) being used, the picture at the top shows LTE Anchor in eNodeB. There would be a need for an ideal backhaul to keep latency in the eNodeB to minimum when combining cellular and WiFi data.

Comparison of link level Carrier Aggregation technologies (Source: Netmanias)

The above table shows comparison between the 3 main techniques for increasing data rates through aggregation; CA, LTE-U/LAA and LTE-H/LWA. While CA has been part of 3GPP Release-10 and is available in more of less all new LTE devices, LTE-U and LTE-H is new and would need modifications in the network as well as in the devices. LTE-H would in the end provide similar benefits to LTE-U but is a safer option from devices and spectrum point of view and would be a more agreeable solution by everyone, including the WiFi community.

A final word; last year we wrote a whitepaper laying out our vision of what 4.5G is. I think we put it simply that in 4.5G, you can use WiFi and LTE at the same time. I think LTE-H fulfills that vision much better than other proposals.

Detailed whitepaper on Carrier Aggregation by 4G Americas

4G Americas has published a detailed whitepaper on Carrier Aggregation (CA). Its a very good detailed document for anyone wishing to study CA.

Two very important features that have come as part of CA enhancements were the multiple timing advance values that came as a part of Release-11 and TDD-FDD joint operation that came part of Release-12

While its good to see that up to 3 carriers CA is now possible as part of Rel-12 and as I mentioned in my last post, we need this to achieve the 'Real' 4G. We have to also remember at the same time that these CA makes the chipsets very complex and may affect the sensitivity of the RF receivers.

Anyway, here is the 4G Americas whitepaper.

LTE Carrier Aggregation Technology Development and Deployment Worldwide from Zahid Ghadialy

You can read more about the 4G Americas whitepaper in their press release here.

Observed Time Difference Of Arrival (OTDOA) Positioning in LTE

Its been a while I wrote anything on Positioning. The network architecture for the positioning entities can be seen from my old blog post here. 

Qualcomm has recently released a whitepaper on the OTDOA (Observed Time Difference Of Arrival) positioning. Its quite a detailed paper with lots of technical insights.

There is also signalling and example of how reference signals are used for OTDOA calculation. Have a look at the whitepaper for detail, embedded below.

Observed Time Difference Of Arrival (OTDOA) Positioning in 3GPP LTE from Zahid Ghadialy

HSPA+ Carrier Aggregation

Came across Qualcomm's HSPA+ Carrier aggregation video (above) and whitepaper. Interesting to see that HSPA/HSPA+ is still growing. As per my earlier post, half of the connections in 2018 would be HSPA/HSPA+.

As can be seen in the picture above, there are quite a few features that may be of interest to the operators. Scalable UMTS is one such feature as I have put in the blog before.

You will notice that upto 4 bands can be aggregated. It would be interesting to see which operators have these bands available and if they would be willing to use HSPA+ CA with upto 4 bands. The presentation by Qualcomm is embedded below and is available to download from here.

Related posts:

• Multipoint HSDPA / HSPA
• HSDPA multiflow data transmission

Quick summary on LTE and UMTS / HSPA Release-12 evolution by 3GPP

A quick summary from 3GPP about the Release-12 progress (Jun. 2014 release planned) from the recent ETSI Future Mobile Summit. Presentation and video embedded below

LTE TDD - universal solution for unpaired spectrum?

TDD deployments are gathering pace. An earlier GSA report I posted here, highlighted the many devices that are TD-LTE ready.

The main thing that is being emphasised is that from the standards point of view, not much additional efforts are required for a TDD device as compared to an FDD device. Of course in practice the physical layer would be different and that could be a challenge in itself.

Qualcomm published a presentation on this topic that is embedded below. Available to download from here.

Our World Without Mobile :-)

Present and Future Technologies for Internet of Things (IoT)

An Interesting presentation from our Future of Wireless Conference (#FWIC2013) in Cambridge earlier this month. A question being asked is what technology will be used for Internet of Things (IoT) or Internet of Everything (IoE) as its also referred to nowadays. These 3 slides below summarises what technologies are see applicable to which scenarios.

Complete slides are embedded below and if you like to see the video, its available here.

Mapping the Future of the Internet of (Every)Thing(s) from Zahid Ghadialy

eMBMS rollouts gathering steam in 2013

Its been a while since I last posted something on eMBMS. Its been even longer that we saw anything official from 3GPP on eMBMS. Recently I have seen some operators again starting to wonder if eMBMS makes business sense, while the vendors and standards are still working hard on the technology.

Not so long back, HEVC/H.265 codec was standardised. This codec helps transmission of the video using half the bandwidth. This means that it would be economical to use this for broadcast technologies. No wonder Nokia, Thompson and NTT Docomo are excited.

Interesting picture from a Qualcomm presentation (embedded in the end) shows how different protocols fit in the eMBMS architecture. My guess would be that the HEVC  may be part of the Codecs.

On the operators front, Korea Telecom (KT) has intentions for countrywide rollout. Korea is one of the very few countries where end users have embraced watching video on small form factors. Verizon wireless has already signalled the intention to rollout eMBMS in 2014; its working out a business case. Telenor Sweden is another player to join the band with the intention of adopting Ericsson's Multi screen technology.

One of the main reasons for the lack of support for the 3G MBMS technology was not a compelling business case. Qualcomm has a whitepaper that outlines some of the potential of LTE Broadcast technology here. A picture from this whitepaper on the business case below:

Finally, a presentation from Qualcomm research on eMBMS embedded below:

LTE eMBMS Technology Overview from Zahid Ghadialy

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.

Videos from the CES 2013

Gorilla glass (above) is made by a company called Corning that is much more well known for its futuristic video, see here.











Finally, this Sony Xperia Z has got over 2 million hits, not exactly sure why so I have added the video for this as well

CSFB Performance

Here is another presentation from Qualcomm from the '4G World'.

CSFB Performance from Zahid Ghadialy

With regards to SI Tunneling mentioned in the presentation, I found the following in another Qualcomm whitepapers:


With Release 9 Enhanced Release with Redirection—SI Tunneling, the device follows 3GPP release 9, where SIB information can be tunneled from the target Radio Access Network (RAN) via the core network to the source RAN and be included in the redirection message sent to the device. This can avoid reading any SIBs on the target cell. 

The predominant solutions deployed today are based on Release 8 Release with Redirection — SIB Skipping, in order to achieve good call setup times, good reliability, and simplify deployments. It is anticipated that Release 9 Enhanced Release with Redirection will be deployed in the near future. At this time, there is not as much push for handover-based CSFB since both Release 8 Release with Redirection—SIB Skipping and Release 9 Enhanced Release with Redirection—SI Tunneling have largely addressed any call setup time issues that may have existed with the Basic Release with Redirection solution.

I have blogged on this topic before, here.

More on Dual Radio here and SVLTE here.

17 LTE Voice Modes

No wonder why LTE chipsets are complicated.

From Qualcomm's presentation in 4G World, available here.

Intelligent Devices and Smart Journeys

Couple of days back, I posted some videos that show technology advancements for the mobile phones. Here is a presentation by Peter Whale from Qualcomm in a recent Cambridge Wireless event about how Sensors and Context-engine will make the future devices much more intelligent then they already are.

Intelligent Devices and Smart Journeys from Zahid Ghadialy

A shameless plug for my presentation on the similar topic from the LTE World Summit 2012, that has now crossed 6000 views, available here.

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?

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.

The 1000x Mobile Data Challenge from Qualcomm Wireless Evolution

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

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

A Twitter discussion on eMBMS

@zahidtg: Samsung has demoed eMBMS using Anritsu RTD system - http://bit.ly/PCGb99  - But is any operator interested?

Korean consumer electronics giant Samsung has successfully demonstrated the clear delivery of television broadcast signals over an LTE 4G wireless network. 

Samsung is using evolved Multimedia Broadcast Multicast Service (eMBMS) technology and has tapped test & measurement specialist Anritsu's Rapid Test Designer (RTD) and MD8430A to simulate the LTE network environment used for the demonstration. 

eMBMS technology allows carriers to adjust coverage and capacity as needed, allowing for more efficient use of network resources in order to better handle the heavy traffic load that broadcast video would present. 

Samsung is actively looking to add more content to the value proposition for its phones. It has deployed its own Hub strategy for its Galaxy line of smartphones, which includes a Music Hub, Movies Hub and Games Hub, all of which give the handset-maker a new incremental revenue stream. A TV Hub that could support live TV content in addition to on-demand episode downloads could add a compelling new wrinkle in that pseudo-walled garden approach. 

Samsung is also instrumental in bringing mobile TV to market via the Dyle initiative for mobile DTV—a service that offers live broadcast feeds from local TV affiliates over separate, dedicated broadcast spectrum. No. 5 U.S. wireless carrier MetroPCS just went live with Dyle service and a Samsung mobile DTV-compatible smartphone.

@KimKLarsen: Depends on whether an operator believes in the broadcast over mobile model. Mobile User trends seems not in favor at least in WEU.

@zahidtg: I agree and thats why I dont think broadcast will work in the short term. Would be different is Apple were to create biz model:)

@KimKLarsen: though the question is whether they (Apple/Google) really need eMBMS for executing such a business model ... I guess not really?!

@KimKLarsen: I have a couple of beautiful white papers on satellite (w & wo terrestrial component) eMBMS using S-band together w Apple or Google

@zahidtg: True. My point is that they are the ones who can create a new biz model on it, operators cant be bothered. Too much hassle.

@KimKLarsen: too much hassle, too little new revenue, risky ROI, insufficient scale, etc.. an Apple or alike might overcome due to shear scale!

@KimKLarsen: though w a satellite (w. city based terrestrial component) based eMBMS system you cover large landmass & pop & get the Scale!

@Qualcomm_Tech: I think the best initial use case for #eMBMS is to selectivley use it as venue casting at stadiums/exhibitons etc.

@kitkilgour: "ClipCasting" has been the main eMBMS use case - stadia, or catching up on your 1min news at stations

@Qualcomm_Tech: True, Any content destined to venue users, incl. live/real-time can leverage eMBMS- huge capacity increase

@KimKLarsen: I agree! Might be interesting! But can this really justify eMBMS as a service for mass adaption?

@KimKLarsen: when will eMBMS be supported in Gobi? & when can we expect this to be standard in all LTE terminal devices?

@kitkilgour: It's networks as well as devices. MBMS has always been hampered by needing to reach the cell edge ...

@kitkilgour: ... with limited / no power control whilst minimising interference to others

@KimKLarsen: great feedback! Thanks! Do you see a need for denser networks to deliver a uniform MBMS service than for standard data services?

@KimKLarsen: one of the challenges we have had in nominal terrestrial MBMS designs have been link budget requirements! Any good sources?

@Qualcomm_Tech: challenge’s been having enough penetration of multicast devices. Venue cast solves that problem #1000x

@KimKLarsen: Sounds like Venue Cast is The Main Driver for eMBMS adoptation? (hmmm?) What's the Revenue Source? #42x

@KimKLarsen: I don't understand how Venue Cast can Drive MC Device Uptake? The other way around more reasonable! #42x

@Qualcomm_Tech: Target specific groups, eg season ticket holders & offer attractive device/content/plan bundles #1000x

Participants:

@zahidtg = Zahid Ghadialy
@KimKLarsen = Dr. Kim Larsen
@Qualcomm_Tech = Qualcomm_Tech
@kitkilgour = Kit Kilgour



In other news, Huawei Launches eMBMS Innovation Center to Develop LTE Solutions:

Huawei, a leading global information and communications technology (ICT) solutions provider, today announced the launch of an enhanced Multimedia Broadcast Multicast Service (eMBMS) innovation center in Shenzhen in order to develop end-to-end eMBMS solutions and LTE applications. 

eMBMS is a 3GPP R9 standard for mobile video that enables a higher transfer capacity over typical MBMS technologies. Huawei's eMBMS innovation center will focus on on-demand video services and broadcast information based on eMBMS. This will enrich LTE applications and accelerate the development of the eMBMS industry chain, which includes chipsets, devices, and network equipment.

In addition to developing solutions, the innovation center will also serve as an experience center for operators. Video, mobile TV, and advertisements will be showcased via mobile smart devices employing Huawei's eMBMS solution. Global operators from Europe, Asia, the South Pacific and other regions have already visited the center to experience its LTE demonstrations.

Huawei has been committed to the growing mobile video market since 2006. According to the Global mobile Supplier Association's (GSA) “Mobile Broadband Status Report”, over four billion people watch videos on YouTube every day. This large-scale usage is leading to increased revenue. According to a report from Global Industry Analysts, revenue from the mobile video market will reach USD30 billion by 2017. Huawei's eMBMS research team works closely with operators, chipset and device manufactures and other partners to further the development of the industry for the benefit of all end users.

Huawei's LTE division has been committed to providing the best commercially performing network, the best end user experience through devices and innovative services, as well as end-to-end convergent solutions for helping operators with their business success. Huawei's eMBMS innovation center will push the development of mobile video well into the future.

Heterogeneous Networks 3G and 4G / LTE-A

There is an excellent presentation and video on Hetnets by Qualcomm that is embedded below:

Heterogeneous Networks 3G and 4G from Zahid Ghadialy