5G Spectrum Discussions

While most people are looking at 5G from the point of new technologies, innovative use cases and even lumping everything under sun as part of 5G, many are unaware of the importance of spectrum and the recently concluded ITU World Radio Conference 2015 (WRC-15).

As can be seen in the picture above, quite a few bands above 24GHz were identified for 5G. Some of these bands have an already existing allocation for mobile service on primary basis. What this means is that mobile services can be deployed in these bands. For 3G and 4G, the spectrum used was in bands below 4GHz, with 1800MHz being the most popular band. Hence there was never a worry for those high frequency bands being used for mobile communication.

As these bands have now been selected for study by ITU, 5G in these bands cannot be deployed until after WRC-19, where the results of these studies will be presented. There is a small problem though. Some of the bands that were initially proposed for 5G, are not included in this list of bands to be studied. This means that there is a possibility that some of the proponent countries can go ahead and deploy 5G in those bands.

For three bands that do not already have mobile services as primary allocation, additional effort will be required to have mobile as primary allocation for them. This is assuming that no problems are identified as a result of studies going to be conducted for feasibility of these bands for 5G.

To see real benefits of 5G, an operator would need to use a combination of low and high frequency bands as can be seen in the picture above. Low frequencies for coverage and high frequencies for capacity and higher data rates.


As I mentioned in an earlier blog post, 5G will be coming in two phases. Phase 1 will be Rel-15 in H2, 2018 and Phase 2, Rel-16, in Dec. 2019. Phase 1 of 5G will generally consist of deployment in lower frequency bands as the higher frequency bands will probably get an approval after WRC-19. Once these new bands have been cleared for 5G deployment, Phase 2 of 5G would be ready for deployment of these high frequency bands.

This also brings us to the point that 5G phase 1 wont be significantly different from LTE-A Pro (or 4.5G). It may be slightly faster and maybe a little bit more efficient.

One thing I suspect that will happen is start of switching off of 3G networks. The most commonly used 3G (UMTS) frequency is 2100MHz (or 2.1GHz). If a network has to keep some 3G network running, it will generally be this frequency. This will also allow other international users to roam onto that network. All other 3G frequencies would soon start migrating to 4G or maybe even 5G phase 1.

Anyway, 2 interesting presentations on 5G access and Future of mmWave spectrum are embedded below. They are both available to download from the UK Spectrum Policy Forum (SPF) notes page here.

Further reading:

• WRC-2015 and the impossible task of achieving a delicate balance

End to end and top to bottom network design…

A good way to start 2016 is by a lecture delivered by Andy Sutton, EE at the IET conference 'Towards 5G Mobile Technology – Vision to Reality'. The slides and the video are both embedded below. The video also contains Q&A at the end which people may find useful.

Videos of all other presentations from the conference are available here for anyone interested.

Top 10 posts for 2015

Here are the top 10 posts for 2015:

1. Voice over WiFi (VoWiFi) technical details
2. LTE-Hetnet (LTE-H) a.k.a. LTE Wi-Fi Link Aggregation (LWA)
3. New LTE UE Categories: 11, 12, 13 and 14 in 3GPP Rel-12
4. LTE Category-0 low power M2M devices
5. VoLTE Roaming: LBO, S8HR or HBO
6. M2M embedded UICC (eSIM) Architecture and Use Cases
7. The path from 4.5G to 5G
8. Quick Summary of LTE Voice Summit 2015 (#LTEVoice)
9. 5G and Evolution of the Inter-connected Network
10. Cellular IoT (CIoT) or LoRa?

Its interesting to see that Voice (VoLTE, VoWiFi, etc.) and M2M dominated most of the searches followed by 5G

ADS-B to enable global flight tracking

One of the things that the World Radio Conference 2015 (WRC-15) enabled was to provide a universal spectrum allocation for flight tracking. What this means in simple terms is that once completely implemented, flights will hopefully no longer be lost, like MH370. It will now be possible to accurately track flights with satellites across nearly 100% of the globe, up from 30% today, by 2018.

To make you better understand this, see this video below:


Automatic Dependent Surveillance (ADS) is a surveillance technique in which aircraft automatically provide, via a data link, data derived from on-board navigation and position-fixing systems, including aircraft identification, four-dimensional position and additional data as appropriate. ADS data is displayed to the controller on a screen that replicates a radar screen. ICAO Doc 4444 PANS-ATM notes that air traffic control service, may be predicated on the use of ADS provided that identification of the aircraft involved is unambiguously established. Two main versions of ADS are currently in use:

• Automatic Dependent Surveillance-Broadcast (ADS-B) is a function on an aircraft or surface vehicle that broadcasts position, altitude, vector and other information for use by other aircraft, vehicles and by ground facilities. It has become the main application of the ADS principle.
• Automatic Dependent Surveillance-Contract (ADS-C) functions similarly to ADS-B but the data is transmitted based on an explicit contract between an ANSP and an aircraft. This contract may be a demand contract, a periodic contract, an event contract and/or an emergency contract. ADS-C is most often employed in the provision of ATS over transcontinental or transoceanic areas which see relatively low traffic levels. 

The ITU press release on this topic:

The frequency band 1087.7-1092.3 MHz has been allocated to the aeronautical mobile-satellite service (Earth-to-space) for reception by space stations of Automatic Dependent Surveillance-Broadcast (ADS-B) emissions from aircraft transmitters.

The frequency band 1087.7-1092.3 MHz is currently being utilized for the transmission of ADS-B signals from aircraft to terrestrial stations within line-of-sight. The World Radiocommunication Conference (WRC-15) has now allocated this frequency band in the Earth-to-space direction to enable transmissions from aircraft to satellites. This extends ADS-B signals beyond line-of-sight to facilitate reporting the position of aircraft equipped with ADS-B anywhere in the world, including oceanic, polar and other remote areas.

WRC-15 recognized that as the standards and recommended practices (SARP) for systems enabling position determination and tracking of aircraft are developed by the International Civil Aviation Organization (ICAO), the performance criteria for satellite reception of ADS-B signals will also need to be addressed by ICAO.

This agreement follows the disappearance and tragic loss of Malaysian Airlines Flight MH370 in March 2014 with 239 people on board, which spurred worldwide discussions on global flight tracking and the need for coordinated action by ITU and other relevant organizations.

For more details see: globalflightsafety.org

LTE-Advanced Pro (a.k.a. 4.5G)

3GPP announced back in October that the next evolution of the 3GPP LTE standards will be known as LTE-Advanced Pro. I am sure this will be shortened to LTE-AP in presentations and discussions but should not be confused with access points.

3GPP Approves LTE-Advanced Pro as New Marker for LTE Evolution System (4.5G) - https://t.co/J3H7lhqAeZ pic.twitter.com/rQmAeooQqd

— Zahid Ghadialy (@zahidtg) October 28, 2015

The 3GPP press release mentioned the following:

LTE-Advanced Pro will allow mobile standards users to associate various new features – from the Release’s freeze in March 2016 – with a distinctive marker that evolves the LTE and LTE-Advanced technology series.

The new term is intended to mark the point in time where the LTE platform has been dramatically enhanced to address new markets as well as adding functionality to improve efficiency.

The major advances achieved with the completion of Release 13 include: MTC enhancements, public safety features – such as D2D and ProSe - small cell dual-connectivity and architecture, carrier aggregation enhancements, interworking with Wi-Fi, licensed assisted access (at 5 GHz), 3D/FD-MIMO, indoor positioning, single cell-point to multi-point and work on latency reduction. Many of these features were started in previous Releases, but will become mature in Release 13.

LTE-evolution timelinea 350pxAs well as sign-posting the achievements to date, the introduction of this new marker confirms the need for LTE enhancements to continue along their distinctive development track, in parallel to the future proposals for the 5G era.

Some vendors have been exploring ways of differentiating the advanced features of Release-13 and have been using the term 4.5G. While 3GPP does not officially support 4.5G (or even 4G) terminology, a new term has been welcomed by operators and vendors alike.

I blogged about Release-13 before, here, which includes a 3GPP presentation and 4G Americas whitepaper. Recently Nokia (Networks) released a short and sweet video and a whitepaper. Both are embedded below:

The Nokia whitepaper (table of contents below) can be downloaded from here.

ITU Workshop on VoLTE and ViLTE Interoperability

ITU recently held a workshop on "Voice and Video Services Interoperability Over Fixed-Mobile Hybrid Environments,Including IMT-Advanced (LTE)" in Geneva, Switzerland on 1st December 2015.

The following is the summary of that workshop:

I also like this presentation by R&S:

All the presentations from the workshop are available online from ITU website here.

Mobility challenges in Future Cities

I got an opportunity this week to attend an interesting 'Sir Henry Royce Memorial Lecture 2015' organised by The IET. The topic of the presentation was "Mobility for the 21st Century".

Professor John Miles reflected upon the reasons why the car dominates our urban environments and explored the challenges of freeing our cities from the log-jam of traffic congestion and associated pollution which currently seems inevitable. He proposition that, to be successful, future public transport and shared ridership systems must simply represent a better journey option than taking the car. The question is, as engineers, how we might meet this challenge and deliver success in the coming decades?

Some reactions from twitter:

Doesn’t make sense to kick people out of cars but to offer public transport systems that are _simply the best_ – Prof John Miles #IETroyce

— Nico Macdonald (@Nico_Macdonald) December 1, 2015

Idle capacity is the reason why public transportation emissions are not much better than cars... #IETroyce pic.twitter.com/Apr5IJsi9i

— Maria Shiao (@mariashiao) December 1, 2015

This is the scalable bus : minimises parasitic mass! #IETroyce pic.twitter.com/k5hZ7dSAFu

— Maria Shiao (@mariashiao) December 1, 2015

Anyway, the video of the presentation is as follows:





Related news:

• Could Driverless cars be heading to Cambridge thanks to UK Autodrive project?

5G, NFV and Network Slicing

5G networks have multifaceted requirements where the network needs to be optimised for data rate, delay and connection numbers. While some industry analysts suspect that these requirements cannot be met by a single network, vendors suggest that Network Slicing will allow all these requirements to be met by a single network.

Ericsson's whitepaper provides a good definition of what network slicing means:

A logical instantiation of a network is often called a network slice. Network slices are possible to create with both legacy platforms and network functions, but virtualization technologies substantially lower barriers to using the technology, for example through increased flexibility and decreased costs.

...

Another aspect of management and network slicing is setting up separate management domains for different network slices. This may allow for completely separate management of different parts of the network that are used for different purposes. Examples of use cases include mobile virtual network operators (MVNOs) and enterprise solutions. This kind of network slice would, in current Evolved Packet Core (EPC) networks, only cover the PDN gateway (PGW) and the policy control resource function (PCRF). However, for machine type communication (MTC) and machine-tomachine (M2M) solutions, it is likely that it would also cover the Mobile Management Entities (MMEs) and Serving Gateways (SGWs).

NGMN came out with the 5G whitepaper which touched on this subject too: 

Figure above illustrates an example of multiple 5G slices concurrently operated on the same infrastructure. For example, a 5G slice for typical smartphone use can be realized by setting fully-fledged functions distributed across the network. Security, reliability and latency will be critical for a 5G slice supporting automotive use case. For such a slice, all the necessary (and potentially dedicated) functions can be instantiated at the cloud edge node, including the necessary vertical application due to latency constraints. To allow on-boarding of such a vertical application on a cloud node, sufficient open interfaces should be defined. For a 5G slice supporting massive machine type devices (e.g., sensors), some basic C-plane functions can be configured, omitting e.g., any mobility functions, with contentionbased resources for the access. There could be other dedicated slices operating in parallel, as well as a generic slice providing basic best-effort connectivity, to cope with unknown use cases and traffic. Irrespective of the slices to be supported by the network, the 5G network should contain functionality that ensures controlled and secure operation of the network end-to-end and at any circumstance.

Netmanias has a detailed article on this topic which is quite interesting too, its available here.

Recently, South Korean operator SK Telecom and Ericsson concluded a successful trial of this technology, see here. Ericsson is also working with NTT Docomo on 5G including network slicing, see here.

'Mobile Edge Computing' (MEC) or 'Fog Computing' (fogging) and 5G & IoT

Picture Source: Cisco

The clouds are up in the sky whereas the fog is low, on the ground. This is how Fog Computing is referred to as opposed to the cloud. Fog sits at the edge (that is why edge computing) to reduce the latency and do an initial level of processing thereby reducing the amount of information that needs to be exchanged with the cloud.

The same paradigm is being used in case of 5G to refer to edge computing, which is required when we are referring to 1ms latency in certain cases.

As this whitepaper from Ovum & Eblink explains:

Mobile Edge Computing (MEC): Where new processing capabilities are introduced in the base station for new applications, with a new split of functions and a new interface between the baseband unit (BBU) and the remote radio unit (RRU).
...
Mobile Edge Computing (MEC) is an ETSI initiative, where processing and storage capabilities are placed at the base station in order to create new application and service opportunities. This new initiative is called “fog computing” where computing, storage, and network capabilities are deployed nearer to the end user.

MEC contrasts with the centralization principles discussed above for C-RAN and Cloud RAN. Nevertheless, MEC deployments may be built upon existing C-RAN or Cloud RAN infrastructure and take advantage of the backhaul/fronthaul links that have been converted from legacy to these new centralized architectures.

MEC is a long-term initiative and may be deployed during or after 5G if it gains support in the 5G standardization process. Although it is in contrast to existing centralization efforts, Ovum expects that MEC could follow after Cloud RAN is deployed in large scale in advanced markets. Some operators may also skip Cloud RAN and migrate from C-RAN to MEC directly, but MEC is also likely to require the structural enhancements that C-RAN and Cloud RAN will introduce into the mobile network.

The biggest challenge facing MEC in the current state of the market is its very high costs and questionable new service/revenue opportunities. Moreover, several operators are looking to invest in C-RAN and Cloud RAN in the near future, which may require significant investment to maintain a healthy network and traffic growth. In a way, MEC is counter to the centralization principle of Centralized/Cloud RAN and Ovum expects it will only come into play when localized applications are perceived as revenue opportunities.

And similarly this Interdigital presentation explains:

Extends cloud computing and services to the edge of the network and into devices. Similar to cloud, fog provides network, compute, storage (caching) and services to end users. The distinguishing feature of Fog reduces latency & improves QoS resulting in a superior user experience

Here is a small summary of the patents with IoT and Fog Computing that has been flied.

Cellular IoT (CIoT) or LoRa?

Back in September, 3GPP reached a decision to standardise NarrowBand IOT (NB-IOT). Now people familiar with the evolution of LTE-A UE categories may be a bit surprised with this. Upto Release-11, the lowest data rate device was UE Cat-1, which could do 10Mbps in DL and 5Mbps in UL. This was power hungry and not really that useful for low data rate sensor devices. Then we got Cat-0 as part of Release-12 which simplified the design and have 1Mbps in DL & UL.

Things start to become a bit complex in Release-13. The above picture from Qualcomm explains the evolution and use cases very well. However, to put more details to the above picture, here is some details from the 4G Americas whitepaper (embedded below)

In support of IoT, 3GPP has been working on all several related solutions and generating an abundance of LTE-based and GSM-based proposals. As a consequence, 3GPP has been developing three different cellular IoT standard- solutions in Release-13:

• LTE-M, based on LTE evolution
• EC-GSM, a narrowband solution based on GSM evolution, and
• NB-LTE, a narrowband cellular IoT solution, also known as Clean Slate technologies

However, in October 2015, the 3GPP RAN body mutually agreed to study the combination of the two different narrowband IoT technical solutions, EC-GSM and NB-LTE, for standardization as a single NB-IoT technology until the December 2015 timeframe. This is in consideration of the need to support different operation modes and avoid divided industry support for two different technical solutions. It has been agreed that NB-IoT would support three modes of operation as follows:

• ‘Stand-alone operation’ utilizing, for example, the spectrum currently being used by GERAN systems as a replacement of one or more GSM carriers,
• ‘Guard band operation’ utilizing the unused resource blocks within a LTE carrier’s guard-band, and
• ‘In-band operation’ utilizing resource blocks within a normal LTE carrier.

Following is a brief description of the various standard solutions being developed at 3GPP by October 2015:

LTE-M: 3GPP RAN is developing LTE-Machine-to-Machine (LTE-M) specifications for supporting LTE-based low cost CIoT in Rel-12 (Low-Cost MTC) with further enhancements planned for Rel-13 (LTE eMTC). LTE-M supports data rates of up to 1 Mbps with lower device cost and power consumption and enhanced coverage and capacity on the existing LTE carrier.

EC-GSM: In the 3GPP GERAN #62 study item “Cellular System Support for Ultra Low Complexity and Low Throughput Internet of Things”, narrowband (200 kHz) CIoT solutions for migration of existing GSM carriers sought to enhance coverage by 20 dB compared to legacy GPRS, and achieve a ten year battery life for devices that were also cost efficient. Performance objectives included improved indoor coverage, support for massive numbers of low-throughput devices, reduced device complexity, improved power efficiency and latency. Extended Coverage GSM (EC-GSM) was fully compliant with all five performance objectives according to the August 2015 TSG GERAN #67 meeting report. GERAN will continue with EC-GSM as a work item within GERAN with the expectation that standards will be frozen by March 2016. This solution necessarily requires a GSM network.

NB-LTE: In August 2015, work began in 3GPP RAN Rel-13 on a new narrowband radio access solution also termed as Clean Slate CIoT. The Clean Slate approach covers the Narrowband Cellular IoT (NB-CIoT), which was the only one of six proposed Clean Slate technologies compliant against a set of performance objectives (as noted previously) in the TSG GERAN #67 meeting report and will be part of Rel-13 to be frozen in March 2016. Also contending in the standards is Narrowband LTE Evolution (NB-LTE) which has the advantage of easy deployment across existing LTE networks.

Rel-12 introduces important improvements for M2M like lower device cost and longer battery life. Further improvements for M2M are envisioned in Rel-13 such as enhanced coverage, lower device cost and longer battery life. The narrowband CIoT solutions also aim to provide lower cost and device power consumption and better coverage; however, they will also have reduced data rates. NB CleanSlate CIoT is expected to support data rates of 160bps with extended coverage.

Table 7.1 provides some comparison of the three options to be standardized, as well as the 5G option, and shows when each release is expected to be finalized.

Another IoT technology that has been giving the cellular IoT industry run for money is the LoRa alliance. I blogged about LoRa in May and it has been a very popular post. A extract from a recent article from Rethink Research as follows:

In the past few weeks, the announcements have been ramping up. Semtech (the creator of the LoRa protocol itself, and the key IP owner) has been most active, announcing that The Lace Company, a wireless operator, has deployed LoRa network architecture in over a dozen Russian cities, claiming to cover 30m people over 9,000km2. Lace is currently aiming at building out Russian coverage, but will be able to communicate to other LoRa devices over the LoRa cloud, as the messages are managed on cloud servers once they have been transmitted from end-device to base unit via LoRaWAN.

“Our network allows the user to connect to an unlimited number of smart sensors,” said Igor Shirokov, CEO of Lace Ltd. “We are providing connectivity to any device that supports the open LoRaWAN standard. Any third party company can create new businesses and services in IoT and M2M market based on our network and the LoRaWAN protocol.”

Elsewhere, Saudi Arabian telco Du has launched a test LoRa network in Dubai, as part of a smart city test project. “This is a defining moment in the UAE’s smart city transformation,” said Carlos Domingo, senior executive officer at Du. “We need a new breed of sensor friendly network to establish the smart city ecosystem. Thanks to Du, this capability now exists in the UAE Today we’ve shown how our network capabilities and digital know-how can deliver the smart city ecosystem Dubai needs. We will not stop in Dubai; our deployment will continue country-wide throughout the UAE.”

But the biggest recent LoRa news is that Orange has committed itself to a national French network rollout, following an investment in key LoRa player Actility. Orange has previously trialed a LoRa network in Grenoble, and has said that it opted for LoRa over Sigfox thanks to its more open ecosystem – although it’s worth clarifying here that Semtech still gets a royalty on every LoRa chip that’s made, and will continue to do so until it chooses not to or instead donates the IP to the non-profit LoRa Alliance itself.

It would be interesting to see if this LoRa vs CIoT ends up the same way as WiMAX vs LTE or not.

Embedded below is the 4G Americas whitepaper as well as a LoRa presentation from Semtech:

Further reading:

• Sigfox and LoRa march onwards as Weightless releases dev kit; the race to gain a foothold before the arrival of the LTE equivalents - Rethink Research
• The LoRa® Alliance Launches the LoRaWAN™ Certification Program
• Semtech LoRa Community Overview
• Consortium including Orange and Foxconn backs LoRa IoT startup Actility
• Harmonizing the industry on a narrowband IoT (NB-IoT) specification
• New LTE standard for Internet of Things gets push from 3GPP