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Latest news and information on 3G, 4G, 5G wireless and technologies in general.
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    The 5G NR (New Radio) plan was finalised in March (3GPP press release) and as a result Non-StandAlone (NSA) 5G NR will be finalised by March 2018. The final 3GPP Release-15 will nevertheless include NR StandAlone (SA) mode as well.

    NSA is based on Option 3 (proposed by DT). If you dont know much about this, then I suggest listening to Andy Sutton's lecture here.


    3GPP TR 38.804: Technical Specification Group Radio Access Network; Study on New Radio Access Technology; Radio Interface Protocol Aspects provides the overall architecture as shown above

    Compared to LTE the big differences are:

    • Core network control plane split into AMF and SMF nodes (Access and Session Management Functions). A given device is assigned a single AMF to handle mobility and AAA roles but can then have multiple SMF each dedicated to a given network slice
    • Core network user plane handled by single node UPF (User Plane Function) with support for multiple UPF serving the same device and hence we avoid need for a common SGW used in LTE. UPF nodes may be daisy chained to offer local breakout and may have parallel nodes serving the same APN to assist seamless mobility.

    Hat tip Alistair Urie.
    Notice that like eNodeB (eNB) in case of LTE, the new radio access network is called gNodeB (gNB). Martin Sauter points out in his excellent blog that 'g' stands for next generation.

    3GPP TS 23.501: Technical Specification Group Services and System Aspects; System Architecture for the 5G System; Stage 2 provides architecture model and concepts including roaming and non-roaming architecture. I will probably have to revisit as its got so much information. The QoS table is shown above. You will notice the terms QFI (QoS Flow Identity) & 5QI (5G QoS Indicator). I have a feeling that there will be a lot of new additions, especially due to URLLC.

    Finally, here are the specifications (hat tip Eiko Seidel for his excellent Linkedin posts - references below):
    5G NR will use 38 series (like 25 series for 3G & 36 series for 4G).

    RAN3 TR 38.801 v2.0.0 on Study on New Radio Access Technology; Radio Access Architecture and Interfaces

    RAN1 TR 38.802 v2.0.0 on Study on New Radio (NR) Access Technology; Physical Layer Aspects

    RAN4 TR 38.803 v2.0.0 on Study on New Radio Access Technology: RF and co-existence aspects

    RAN2 TR 38.804 v1.0.0 on Study on New Radio Access Technology; Radio Interface Protocol Aspects

    38.201 TS Physical layer; General description
    38.211 TS Physical channels and modulation
    38.212 TS Multiplexing and channel coding
    38.213 TS Physical layer procedures
    38.214 TS Physical layer measurements
    38.21X TS Physical layer services provided to upper layer
    38.300 TS Overall description; Stage-2
    38.304 TS User Equipment (UE) procedures in idle mode
    38.306 TS User Equipment (UE) radio access capabilities
    38.321 TS Medium Access Control (MAC) protocol specification
    38.322 TS Radio Link Control (RLC) protocol specification
    38.323 TS Packet Data Convergence Protocol (PDCP) specification
    38.331 TS Radio Resource Control (RRC); Protocol specification
    37.3XX TS [TBD for new QoS]
    37.3XX TS Multi-Connectivity; Overall description; Stage-2
    38.401 TS Architecture description
    38.410 TS NG general aspects and principles
    38.411 TS NG layer 1
    38.412 TS NG signalling transport
    38.413 TS NG Application Protocol (NGAP)
    38.414 TS NG data transport
    38.420 TS Xn general aspects and principles
    38.421 TS Xn layer 1
    38.422 TS Xn signalling transport
    38.423 TS Xn Application Protocol (XnAP)
    38.424 TS Xn data transport
    38.425 TS Xn interface user plane protocol
    38.101 TS User Equipment (UE) radio transmission and reception
    38.133 TS Requirements for support of radio resource management
    38.104 TS Base Station (BS) radio transmission and reception
    38.307 TS Requirements on User Equipments (UEs) supporting a release-independent frequency band
    38.113 TS Base Station (BS) and repeater ElectroMagnetic Compatibility (EMC)
    38.124 TS Electromagnetic compatibility (EMC) requirements for mobile terminals and ancillary equipment
    38.101 TS User Equipment (UE) radio transmission and reception
    38.133 TS Requirements for support of radio resource management
    38.104 TS Base Station (BS) radio transmission and reception
    38.141 TS Base Station (BS) conformance testing

    Note that all specifications are not in place yet. Use this link to navigate 3GPP specs: http://www.3gpp.org/ftp/Specs/archive/38_series/

    Further reading:




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    I have seen many people wondering if so many different types of IoT technologies are needed, 3GPP or otherwise. The story behind that is that for many years 3GPP did not focus too much on creating an IoT variant of the standards. Their hope was that users will make use of LTE Cat 1 for IoT and then later on they created LTE Cat 0 (see here and here).

    The problem with this approach was that the market was ripe for a solution to a different types of IoT technologies that 3GPP could not satisfy. The table below is just an indication of the different types of technologies, but there are many others not listed in here.


    The most popular IoT (or M2M) technology to date is the humble 2G GSM/GPRS. Couple of weeks back Vodafone announced that it has reached a milestone of 50 million IoT connections worldwide. They are also adding roughly 1 million new connections every month. The majority of these are GSM/GPRS.

    Different operators have been assessing their strategy for IoT devices. Some operators have either switched off or are planning to switch off they 2G networks. Others have a long term plan for 2G networks and would rather switch off their 3G networks to refarm the spectrum to more efficient 4G. A small chunk of 2G on the other hand would be a good option for voice & existing IoT devices with small amount of data transfer.

    In fact this is one of the reasons that in Release-13 GSM is being enhanced for IoT. This new version is known as Extended Coverage – GSM – Internet of Things (EC-GSM-IoT ). According to GSMA, "It is based on eGPRS and designed as a high capacity, long range, low energy and low complexity cellular system for IoT communications. The optimisations made in EC-GSM-IoT that need to be made to existing GSM networks can be made as a software upgrade, ensuring coverage and accelerated time to-market. Battery life of up to 10 years can be supported for a wide range use cases."

    The most popular of the non-3GPP IoT technologies are Sigfox and LoRa. Both these technologies have gained significant ground and many backers in the market. This, along with the gap in the market and the need for low power IoT technologies that transfer just a little amount of data and has a long battery life motivated 3GPP to create new IoT technologies that were standardised as part of Rel-13 and are being further enhanced in Rel-14. A summary of these technologies can be seen below


    If you look at the first picture on the top (modified from Qualcomm's original here), you will see that these different IoT technologies, 3GPP or otherwise address different needs. No wonder many operators are using the unlicensed LPWA IoT technologies as a starting point, hoping to complement them by 3GPP technologies when ready.

    Finally, looks like there is a difference in understanding of standards between Ericsson and Huawei and as a result their implementation is incompatible. Hopefully this will be sorted out soon.


    Market Status:

    Telefonica has publicly said that Sigfox is the best way forward for the time being. No news about any 3GPP IoT technologies.

    Orange has rolled outLoRa network but has said that when NB-IoT is ready, they will switch the customers on to that.

    KPN deployed LoRa throughout the Netherlands thereby making it the first country across the world with complete coverage. Haven't ruled out NB-IoT when available.

    SK Telecom completed nationwide LoRa IoT network deployment in South Korea last year. It sees LTE-M and LoRa as Its 'Two Main IoT Pillars'.

    Deutsche Telekom has rolled out NarrowBand-IoT (NB-IoT) Network across eight countries in Europe (Germany, the Netherlands, Greece, Poland, Hungary, Austria, Slovakia, Croatia)

    Vodafone is fully committed to NB-IoT. Their network is already operational in Spain and will be launching in Ireland and Netherlands later on this year.

    Telecom Italia is in process of launching NB-IoT. Water meters in Turin are already sending their readings using NB-IoT.

    China Telecom, in conjunction with Shenzhen Water and Huawei launched 'World's First' Commercial NB-IoT-based Smart Water Project on World Water Day.

    SoftBank is deploying LTE-M (Cat-M1) and NB-IoT networks nationwide, powered by Ericsson.

    Orange Belgium plans to roll-out nationwide NB-IoT& LTE-M IoT Networks in 2017

    China Mobile is committed to 3GPP based IoT technologies. It has conducted outdoor trials of NB-IoT with Huawei and ZTE and is also trialing LTE-M with Ericsson and Qualcomm.

    Verizon has launched Industry’s firstLTE-M Nationwide IoT Network.

    AT&Twill be launchingLTE-M network later on this year in US as well as Mexico.


    Further reading:


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    I made an attempt to place the different cellular and non-cellular LPWA technologies together in a picture in my last post here. Someone pointed out that these pictures above, from LoRa alliance whitepaper are even better and I agree.

    Most IoT technologies lists their battery life as 10 years. There is an article in Medium rightly pointing out that in Verizon's LTE-M network, IoT devices battery may not last very long.

    The problem is that 10 years battery life is headline figure and in real world its sometimes not that critical. It all depends on the application. For example this Iota Pet Tracker uses Bluetooth but only claims battery life of  "weeks". I guess ztrack based on LoRa would give similar results. I have to admit that non-cellular based technologies should have longer battery life but it all depends on applications and use cases. An IoT device in the car may not have to worry too much about power consumption. Similarly a fleet tracker that may have solar power or one that is expected to last more than the fleet duration, etc.


    So coming back to the power consumption. Martin Sauter in his excellent Wireless Moves blog post, provided the calculation that I am copying below with some additions:

    The calculation can be found in 3GPP TR 45.820, for NB-IoT in Chapter 7.3.6.4 on ‘Energy consumption evaluation’.

    The battery capacity used for the evaluation was 5 Wh. That’s about half or even only a third of the battery capacity that is in a smartphone today. So yes, that is quite a small battery indeed. The chapter also contains an assumption on how much power the device draws in different states. In the ‘idle’ state the device is in most often, power consumption is assumed to be 0.015 mW.

    How long would the battery be able to power the device if it were always in the idle state? The calculation is easy and you end up with 38 years. That doesn’t include battery self-discharge and I wondered how much that would be over 10 years. According to the Varta handbook of primary lithium cells, self-discharge of a non-rechargable lithium battery is less than 1% per year. So subtract roughly 4 years from that number.

    Obviously, the device is not always in idle and when transmitting the device is assumed to use 500 mW of power. Yes, with this power consumption, the battery would not last 34 years but less than 10 hours. But we are talking about NB-IoT so the device doesn’t transmit for most of the time. The study looked at different transmission patterns. If 200 bytes are sent once every 2 hours, the device would run on that 5 Wh battery for 1.7 years. If the device only transmits 50 bytes once a day the battery would last 18.1 years.

    So yes, the 10 years are quite feasible for devices that collect very little data and only transmit them once or twice a day.

    The conclusions from the report clearly state:

    The achievable battery life for a MS using the NB-CIoT solution for Cellular IoT has been estimated as a function of reporting frequency and coupling loss. 

    It is important to note that these battery life estimates are achieved with a system design that has been intentionally constrained in two key respects:

    • The NB-CIoT solution has a frequency re-use assumption that is compatible with a stand-alone deployment in a minimum system bandwidth for the entire IoT network of just 200 kHz (FDD), plus guard bands if needed.
    • The NB-CIoT solution uses a MS transmit power of only +23 dBm (200 mW), resulting in a peak current requirement that is compatible with a wider range of battery technologies, whilst still achieving the 20 dB coverage extension objective.  

    The key conclusions are as follows:

    • For all coupling losses (so up to 20 dB coverage extension compared with legacy GPRS), a 10 year battery life is achievable with a reporting interval of one day for both 50 bytes and 200 bytes application payloads.
    • For a coupling loss of 144 dB (so equal to the MCL for legacy GPRS), a 10 year battery life is achievable with a two hour reporting interval for both 50 bytes and 200 bytes application payloads. 
    • For a coupling loss of 154 dB, a 10 year battery life is achievable with a 2 hour reporting interval for a 50 byte application payload. 
    • For a coupling loss of 154 dB with 200 byte application payload, or a coupling loss of 164 dB with 50 or 200 byte application payload, a 10 year battery life is not achievable for a 2 hour reporting interval. This is a consequence of the transmit energy per data bit (integrated over the number of repetitions) that is required to overcome the coupling loss and so provide an adequate SNR at the receiver. 
    • Use of an integrated PA only has a small negative impact on battery life, based on the assumption of a 5% reduction in PA efficiency compared with an external PA.

    Further improvements in battery life, especially for the case of high coupling loss, could be obtained if the common assumption that the downlink PSD will not exceed that of legacy GPRS was either relaxed to allow PSD boosting, or defined more precisely to allow adaptive power allocation with frequency hopping.

    I will look at the technology aspects in a future post how 3GPP made enhancements in Rel-13 to reduce power consumption in CIoT.

    Also have a look this GSMA whitepaper on 3GPP LPWA lists the applications requirements that are quite handy.

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  • 05/12/17--01:15: 5G – Beyond the Hype
  • Dan Warren, former GSMA Technology Director who created VoLTE and coined the term 'Phablet' has been busy with his new role as Head of 5G Research at Samsung R&D in UK. In a presentation delivered couple of days back at Wi-Fi Global Congress he set out a realistic vision of 5G really means.

    A brief summary of the presentation in his own words below, followed by the actual presentation:
    "I started with a comment I have made before – I really hate the term 5G.  It doesn’t allow us to have a proper discussion about the multiplicity of technologies that have been throw under the common umbrella of the term, and hence blurs the rationale for one why each technology is important in its own right.  What I have tried to do in these slides is talk more about the technology, then look at the 5G requirements, and consider how each technology helps or hinders the drive to meet those requirements, and then to consider what that enables in practical terms.

    The session was titled ‘5G – beyond the hype’ so in the first three slides I cut straight to the technology that is being brought in to 5G.  Building from the Air Interface enhancements, then the changes in topology in the RAN and then looking at the ‘softwarisation’ on the Core Network.  This last group of technologies sets up the friction in the network between the desire to change the CapEx model of network build by placing functions in a Cloud (both C-RAN and an NFV-based Core, as well as the virtualisation of transport network functions) and the need to push functions to the network edge by employing MEC to reduce latency.  You end up with every function existing everywhere, data breaking out of the network at many different points and some really hard management issues.

    On slide 5 I then look at how these technologies line up to meeting 5G requirements.  It becomes clear that the RAN innovations are all about performance enhancement, but the core changes are about enabling new business models from flexibility in topology and network slicing.  There is also a hidden part of the equation that I call out, which is that while technology enables the central five requirements to be met, they also require massive investment by the Operator.  For example you won’t reach 100% coverage if you don’t build a network that has total coverage, so you need to put base stations in all the places that they don’t exist today.

    On the next slide I look at how network slicing will be sold.  There are three ways in which a network might be sliced – by SLA or topology, by enterprise customer and by MVNO.  The SLA or topology option is key to allowing the co-existence of MEC and Cloud based CN.  The enterprise or sector based option is important for operators to address large vertical industry players, but each enterprise may want a range of SLA’s for different applications and devices, so you end up with an enterprise slice being made up of sub-slices of differing SLA and topology.  Then, an MVNO may take a slice of the network, but will have it’s own enterprise customers that will take a sub-slice of the MVNO slice, which may in turn be made of sub-sub-slices of differing SLAs.  Somewhere all of this has be stitched back together, so my suggestion is that ‘Network Splicing’ will be as important as network slicing.

    Slide illustrates all of this again and notes that there will also be other networks that have been sliced as well, be that 2G, 3G, 4G, WiFi, fixed, LPWA or anything else.  There is also going to be an overarching orchestration requirement both within a network and in the Enterprise customer (or more likely in System Integrator networks who take on the ‘Splicing’ role).  The red flags are showing that Orchestration is both really difficult and expensive, but the challenge for the MNO will also exist in the RAN.  The RRC will be a pinch point that has to sort out all of these device sitting in disparate network topologies with varying demands on the sliced RAN.

    Then, in the next four slides I look at the business model around this.  Operators will need to deal with the realities of B2B or B2B2C business models, where they are the first B. The first ‘B’s price is the second ‘B’s cost, so the operator should expect considerable pressure on what it charges, and to be held contractually accountable for the performance of the network.  If 5G is going to claim 100% coverage, 5 9’s reliability, 50Mbps everywhere and be sold to enterprise customers on that basis, it is going to have to deliver it else there will be penalties to pay.  On the flip side to this, if all operators do meet the 5G targets, then they will become very much the same so the only true differentiation option will be on price.  With the focus on large scale B2B contracts, this has all the hallmarks of a race downwards and commoditisation of connectivity, which will also lead to disintermediation of operators from the value chain on applications.

    So to conclude I pondered on what the real 5G justification is.  Maybe operators shouldn’t be promising everything, since there will be healthy competition on speed, coverage and reliability while those remain as differentiators.  Equally, it could just be that operators will fight out the consumer market share on 5G, but then that doesn’t offer any real uplift in market size, certainly not in mature developed world markets.  The one thing that is sure is that there is a lot of money to be spent getting there."



    Let me know what do you think?

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    A startup on kickstarter is touting world's first voice mask for smartphones. Having said that Hushme has been compared to Bane from Batman and Dr. Hannibal Lecter. Good detail of Hushme at Engadget here.

    This is an interesting concept and has come back in the news after a long gap. Even though we are well past the point of 'Peak Telephony' because we now use text messages and OTT apps for non-urgent communications. Voice will always be around though for not only urgent communications but for things like audio/video conference calls.


    Back in 2003 NTT Docomo generated a lot of news on this topic. Their research paper "Unvoiced speech recognition using EMG - mime speech recognition" was the first step in trying to find a way to speak silently while the other party can hear voice. This is probably the most quoted paper on this topic. (picture source).


    NASA was working on this area around the same time. They referred to this approach as 'Subvocal Speech'. While the original intention of this approach was for astronauts suits, the intention was that it could also be available for other commercial use. Also, NASA was effectively working on limited number of words using this approach (picture source).

    For both the approaches above, there isn't a lot of recent updated information. While it has been easy to recognize certain characters, it takes a lot of effort to do the whole speech. Its also a challenge to play your voice rather than a robotic voice to the other party.

    To give a comparison of how big a challenge this is, look at the Youtube videos where they do an automatic captions generation. Even though you can understand what the person is speaking, its always a challenge for the machine. You can read more about the challenge here.

    A lot of research in similar areas has been done is France and is available here.


    Motorola has gone a step further and patented an e-Tattoo that can be emblazoned over your vocal cords to intercept subtle voice commands — perhaps even subvocal commands, or even the fully internal whisperings that fail to pluck the vocal cords when not given full cerebral approval. One might even conclude that they are not just patenting device communications from a patch of smartskin, but communications from your soul. Read more here.


    Another term used for research has been 'lip reading'. While the initial approaches to lip reading was the same as other approaches of attaching sensors to facial muscles (see here), the newer approaches are looking at exploiting smartphone camera for this.

    Many researchers have achieved reasonable success using cameras for lip reading (see here and here) but researchers from Google’s AI division DeepMind and the University of Oxford have used artificial intelligence to create the most accurate lip-reading software ever.
    Now the challenge with smartphones for using camera for speech recognition will be high speed data connectivity and ability to see lip movement clearly. While in indoor environment this can be solved with Wi-Fi connectivity and looking at the camera, it may be a bit tricky outdoors or not looking at the camera while driving. Who knows, this may be a killer use-case for 5G.

    By the way, this is not complete research in this area. If you have additional info, please help others by adding it in the comments section.

    Related links:




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    Every few years I add Mary Meeker's Internet Trends slides on the blog. Interested people can refer to 2011 and  2014 slide pack to see how world has changed.


    One of the initial slide highlights that the number of smartphones are reached nearly 3 billion by end of 2016. If we looked at this excellent recent post by Tomi Ahonen, there were 3.2 billion smartphones at the end of Q1 2017. Here is a bit of extract from that.

    SMARTPHONE INSTALLED BASE AT END OF MARCH 2017 BY OPERATING SYSTEM

    Rank . OS Platform . . . . Units . . . . Market share  Was Q4 2016
    1 . . . . All Android . . . . . . . . . . . . 2,584 M . . . 81 % . . . . . . ( 79 %)  
    a . . . . . . Pure Android/Play . . . . 1,757 M . . . 55%
    b . . . . . . Forked Anroid/AOSP . . . 827 M . . . 26%
    2 . . . . iOS  . . . . . . . . . . . . . . . . . . 603 M . . . 19 % . . . . . . ( 19 %) 
    Others . . . . . . . . . . . . . . . . . . . . . . 24 M  . . . . 1 % . . . . . . (   1 %)
    TOTAL Installed Base . 3,211 M smartphones (ie 3.2 Billion) in use at end of Q1, 2017

    Source: TomiAhonen Consulting Analysis 25 May 2017, based on manufacturer and industry data


    BIGGEST SMARTPHONE MANUFACTURERS BY UNIT SALES IN Q1 2017

    Rank . . . Manufacturer . Units . . . Market Share . Was Q4 2016 
    1 (2) . . . Samsung . . . .  79.4 M . . 22.7% . . . . . . . ( 17.9% ) 
    2 (1) . . . Apple  . . . . . . . 50.8 M . . 14.5% . . . . . . . ( 18.0% ) 
    3 (3) . . . Huawei  . . . . . . 34.6 M . . . 9.9% . . . . . . . (10.4% ) 
    4 (4) . . . Oppo . . . . . . . . 28.0 M . . . 8.0% . . . . . . . (   7.1% ) 
    5 (5) . . . Vivo . . . . . . . . . 22.0 M . . . 6.3% . . . . . . . (   5.6% ) 
    6 (9) . . . LG  . . . . . . . .  . 14.8 M . . . 4.2% . . . . . . . (   3.3% ) 
    7 (7) . . . Lenovo .  . . . . . 13.2 M . . . 3.8% . . . . . . . (   3.8% )
    8 (8) . . . Gionee . . . . . . . .9.6 M . . . 2.7% . . . . . . .  (   3.5% )
    9 (6) . . . ZTE  . . . . . . . . . 9.2 M . . . 2.6% . . . . . . . (   5.2% ) 
    10 (10) . TCL/Alcatel . . .  8.7 M . . . 2.5% . . . . . . . (  2.4% ) 
    Others . . . . . . . . . . . . . . 80.2 MTOTAL . . . . . . . . . . . . . 350.4 M

    Source: TomiAhonen Consulting Analysis 25 May 2017, based on manufacturer and industry data


    This year, the number of slides have gone up to 355 and there are some interesting sections like China Internet, India Internet, Healthcare, Interactive games, etc. The presentation is embedded below and can be downloaded from slideshare




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    The CEO of UK mobile network operator EE recently announced on twitter that they have achieved 429 Mbps in live network. The following is from their press release:

    EE, the UK’s largest mobile network operator and part of the BT Group, has switched on the next generation of its 4G+ network and demonstrated live download speeds of 429Mbps in Cardiff city centre using Sony’s Xperia XZ Premium, which launched on Friday 2 June. 
    The state of the art network capability has been switched on in Cardiff and the Tech City area of London today. Birmingham, Manchester and Edinburgh city centres will have sites upgraded during 2017, and the capability will be built across central London. Peak speeds can be above 400Mbps with the right device, and customers connected to these sites should be able to consistently experience speeds above 50Mbps. 
    Sony’s Xperia XZ Premium is the UK’s first ‘Cat 16’ smartphone optimised for the EE network, and EE is the only mobile network upgrading its sites to be able to support the new device’s unique upload and download capabilities. All devices on the EE network will benefit from the additional capacity and technology that EE is building into its network. 
    ... 
    The sites that are capable of delivering these maximum speeds are equipped with 30MHz of 1800MHz spectrum, and 35MHz of 2.6GHz spectrum. The 1800MHz carriers are delivered using 4x4 MIMO, which sends and receives four signals instead of just two, making the spectrum up to twice as efficient. The sites also broadcast 4G using 256QAM, or Quadrature Amplitude Modulation, which increases the efficiency of the spectrum.

    Before proceeding further you may want to check out my posts 'Gigabit LTE?' and 'New LTE UE Categories (Downlink & Uplink) in Release-13'

    If you read the press release carefully, EE are now using 65MHz of spectrum for 4G. I wanted to provide a calculation for whats possible in theory with this much bandwidth.

    Going back to basics (detailed calculation for basics in slideshare below), in LTE/LTE-A, the maximum bandwidth possible is 20MHz. Any more bandwidth can be used with Carrier Aggregation. So as per the EE announcement, its 20 + 10 MHz in 1800 band and 20 + 15 MHz in 2600 band

    So for 1800 MHz band:

    50 resource blocks (RBs) per 10MHZ, 150 for 30MHz.
    Each RB has 12x7x2=168 symbols per millisecond in case of normal modulation support cyclic prefix (CP).
    For 150 RBs, 150 x 168 = 25200 symbols per ms or 25,200,000 symbols per second. This can also be written as 25.2 Msps (Mega symbols per second)
    256 QAM means 8 bits per symbol. So the calculation changes to 25.2 x 8 = 201.6 Mbps. Using 4 x 4 MIMO, 201.6 x 4 = 806.4Mbps
    Removing 25% overhead which is used for signalling, this gives 604.80 Mbps


    Repeating the same exercise for 35MHz of 2600 MHz band, with 2x2 MIMO and 256 QAM:

    175 x 168 = 29400 symbols per ms or 29,400,000 symbols per second. This can be written as 29.4 Msps
    29.4 x 8 = 235.2 Mbps
    Using 2x2 MIMO, 235.2 x 2 = 470.4 Mbps
    Removing 25% overhead which is used for signalling, this gives 352.80 Mbps

    The combined theoretical throughput for above is 957.60 Mbps

    For those interested in revisiting the basic LTE calculations, here is an interesting document:




    Further reading:


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    5G is becoming a case of 'damned if you do damned if you don't'. Behind the headlines of new achievements and faster speeds lies the reality that many operators are struggling to keep afloat. Indian and Nigerian operators are struggling with heavy debt and it wont be a surprise if some of the operators fold in due course.

    With increasing costs and decreasing revenues, its no surprise that operators are looking at ways of keeping costs down. Some operators are postponing their 5G plans in favour of Gigabit LTE. Other die hard operators are pushing ahead with 5G but looking at ways to keep the costs down. In Japan for example, NTT DOCOMO has suggested sharing 5G base stations with its two rivals to trim costs, particularly focusing efforts in urban areas.


    In this post, I am looking to summarise an old but brilliant post by Dr. Kim Larsen here. While it is a very well written and in-depth post, I have a feeling that many readers may not have the patience to go through all of it. All pictures in this post are from the original post by Dr. Kim Larsen.


    Before embarking on any Network sharing mission, its worthwhile asking the 5W's (Who, Why, What, Where, When) and 2H's (How, How much).

    • Why do you want to share?
    • Who to share with? (your equal, your better or your worse).
    • What to share? (sites, passives, active, frequencies, new sites, old sites, towers, rooftops, organization, ,…).
    • Where to share? (rural, sub-urban, urban, regional, all, etc..).
    • When is a good time to start sharing? During rollout phase, steady phase or modernisation phase. See picture below. For 5G, it would make much more sense that network sharing is done from the beginning, i.e., Rollout Phase


    • How to do sharing?. This may sound like a simple question but it should take account of regulatory complexity in a country. The picture below explains this well:



    • How much will it cost and how much savings can be attained in the long term? This is in-fact a very important question because the end result after a lot of hard work and laying off many people may result in an insignificant amount of cost savings. Dr. Kim provides detailed insight on this topic that I find it difficult to summarise. Best option is to read it on his blog.


    An alternative approach to network sharing is national roaming. Many European operators are dead against national roaming as this means the network loses its differentiation compared to rival operators. Having said that, its always worthwhile working out the savings and seeing if this can actually help.

    National Roaming can be attractive for relative low traffic scenarios or in case were product of traffic units and national roaming unit cost remains manageable and lower than the Shared Network Cost.

    The termination cost or restructuring cost, including write-off of existing telecom assets (i.e., radio nodes, passive site solutions, transmission, aggregation nodes, etc….) is likely to be a substantially financial burden to National Roaming Business Case in an area with existing telecom infrastructure. Certainly above and beyond that of a Network Sharing scenario where assets are being re-used and restructuring cost might be partially shared between the sharing partners.

    Obviously, if National Roaming is established in an area that has no network coverage, restructuring and termination cost is not an issue and Network TCO will clearly be avoided, Albeit the above economical logic and P&L trade-offs on cost still applies.

    If this has been useful to understand some of the basics of network sharing, I encourage you to read the original blog post as that contains many more details.

    Futher Reading:




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    3GPP has published an overview of what has been achieved so far in the Mission Critical and also provides an outlook of what can be expected in the near future. A more detailed paper summarizing the use cases and functional aspects of Rel-13, Rel-14 and upcoming Rel-15 will be published later this year.

    Mission Critical Services – Detailed List of Rel-13, Rel-14 and Rel-15 Functionalities

    Rel-13 MCPTT (completed 2016)
    • User authentication and service authorization
    • Configuration
    • Affiliation and de-affiliation
    • Group calls on-network and off-network (within one system or multiple systems, pre-arranged or chat model, late entry, broadcast group calls, emergency group calls, imminent peril group calls, emergency alerts)
    • Private calls on-network and off-network (automatic or manual commencement modes, emergency private calls)
    • MCPTT security
    • Encryption (media and control signalling)
    • Simultaneous sessions for call
    • Dynamic group management (group regrouping)
    • Floor control in on-network (within one system or across systems) and in off-network
    • Pre-established sessions
    • Resource management (unicast, multicast, modification, shared priority)
    • Multicast/Unicast bearer control, MBMS (Multimedia Broadcast/Multicast Service) bearers
    • Location configuration, reporting and triggering
    • Use of UE-to-network relays
    Rel-14 MC Services (completed 2017)
    MC Services Common Functionalities:
    • User authentication and service authorization
    • Service configuration
    • Affiliation and de-affiliation
    • Extended Location Features
    • (Dynamic) Group Management
    • Identity management
    • MC Security framework
    • Encryption (media and control signalling)
    MCPTT Enhancements:
    • First-to-answer call setup (with and without floor control)
    • Floor control for audio cut-in enabled group
    • Updating the selected MC Service user profile for an MC Service
    • Ambient listening call
    • MCPTT private call-back request
    • Remote change of selected group
    MCVideo, Common Functions plus:
    • Group Call (including emergency group calls, imminent peril group calls, emergency alerts)
    • Private Call (off-network)
    • Transmission Control
    MCData, Common Functions plus:
    • Short Data Service (SDS)
    • File Distribution (FD) (on-network)
    • Transmission and Reception Control
    • Handling of Disposition Notifications
    • Communication Release
    Rel-15 MC Services (in progress)

    MC Services Common Functionalities Enhancements:
    • Enhanced MCPTT group call setup procedure with MBMS bearer
    • Enhanced Location management, information and triggers
    • Interconnection between 3GPP defined MC systems
    • Interworking with legacy systems

    MCPTT Enhancements:
    • Remotely initiated MCPTT call
    • Enhanced handling of MCPTT Emergency Alerts
    • Enhanced Broadcast group call
    • Updating pre-selected MC Service user profile
    • Temporary group call - user regroup
    • Functional alias identity for user and equipment
    • Multiple simultaneous users
    MCVideo Additions:
    • Video push
    • Video pull
    • Private call (on-network)
    • Broadcast Group Call
    • Ambient Viewing Call
    • Capability information sharing
    • Simultaneous Sessions
    • Use of MBMS transmission
    • Emergency and imminent peril private communications
    • Primary and Partner MC system interactions for MCVideo communications
    • Remote video parameters control capabilities

    MCData Additions:
    • MCData specific Location
    • Enhanced Status
    • Accessing list of deferred communications
    • Usage of MBMS
    • Emergency Alert
    • Data streaming
    • File Distribution (FD) (off-network)
    • IP connectivity

    Release-14 features will be available by end of September 2017 and many Release-15 features, that is being hurried due to 5G will be available by June 2018.

    For more details, follow the links below:




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    We have just created a (nearly) live IoT tracker for anyone interested in tracking the IoT deployments. The updated version will be available on Slideshare on a regular basis



    Further reading:




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    While we have been discussing IoT these last few weeks, here is another one that I came across. This picture above from a recent Rethink research shows that Wi-SUN is going to enjoy more growth than LoRaWAN or Sigfox. Another recent report by Mobile Experts also makes a mention of this IoT technology.

    I am sure most of the readers have not heard of Wi-SUN, so what exactly is Wi-SUN technology?


    From Rethink Research, The Wi-SUN Alliance was formed in 2011 to form an organization to push adoption of the IEEE 802.15.4g standard, which aimed to improve utility networks using a narrowband wireless technology. The peer-to-peer self-healing mesh has moved from its initial grid focus to encompass smart city applications (especially street lighting), and we spoke to its Chairman, Phil Beecher, to learn more.

    Beecher explained that the non-profit Alliance set about defining subsets of the open standards, testing for interoperability, and certifying compatible products, and soon developed both a Field Area Network (FAN) and a Home Area Network (HAN), which allowed it to move into Home Energy Management Systems (HEMS) in Japan – a country that is leading the curve in HEMS deployments and developments.


    As can be seen in the picture above:

    • Develops technical specifications of Physical Layer (PHY) and Medium Access Control (MAC) layers, with Network layer as required
    • Develop Interoperability test programs to ensure implementations are interoperable
    • Physical layer specification is based on IEEE802.15.4g/4u/4v
    • MAC layer may use different options depending on the application
    • Profile specifications are categorized based on application types

    Picture source for the last three pics, Wi-SUN presentation here.


    A new whitepaper from Wi-SUN Alliance provides comparison of Wi-SUN, LoRaWAN and NB-IoT.

    A recent presentation by Dr. Simon Dunkley in Cambridge Wireless is embedded below:



    Further reading:




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    Today's post is inspired by two things. One of them being my most popular answer on Quora. As you can see, its gathered over 19K upvotes.


    The other being #EEGoldenSIM competition started by Marc Allera, CEO of UK mobile operator, EE,. The users were required to find a mast, take a picture and share it. This led to a lot of people asking how do masts look like and also generated.

    Below is a presentation prepared by my 3G4G colleagues on how different types of antennas and mobile masts look like. Hope you like it.




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    Its been a while since I wrote about LTE-U / LAA on this blog. I have written a few posts on the small cells blog but they seem to be dated as well. For anyone needing a quick refresher on LTE-U / LAA, please head over to IoTforAll or ShareTechNote. This post is not about the technology per se but the overall ecosystem with LTE-U / LAA (and even Multefire) being part of that.

    Lets recap the market status quickly. T-Mobile US has already got LTE-U active and LAA was tested recently. SK Telecom achieved 1Gbps in LAA trials with Ericsson. AT&T has decided to skip the non-standard LTE-U and go to standards based LAA. MTN & Huawei have trialled LAA for in-building in South Africa. All these sound good and inspires confidence in the technology however some observations are worrying me.


    Couple of years back when LTE-U idea was conceived, followed by LAA, the 5GHz channels were relatively empty. Recently I have started to see that they are all filling up.

    Any malls, hotels, service stations or even big buildings I go to, they all seem to be occupied. While supplemental downlink channels are 20MHz each, the Wi-Fi channels could be 20MHz, 40MHz, 80MHz or even 160MHz.

    On many occasions I had to switch off my Wi-Fi as the speeds were so poor (due to high number of active users) and go back to using 4G. How will it impact the supplemental downlink in LTE-U / LAA? How will it impact the Wi-Fi users?

    On my smartphone, most days I get 30/40Mbps download speeds and it works perfectly fine for all my needs. The only reason we would need higher speeds is to do tethering and use laptops for work, listen to music, play games or watch videos. Most people I know or work with dont require gigabit speeds at the moment.

    Once a user that is receiving high speeds data on their device using LTE-U / LAA creates a Wi-Fi hotspot, it may use the same 5GHz channels as the ones that the network is using for supplemental downlink. How do you manage this interference? I am looking forward to discussions on technical fora where users will be asking why their download speeds fall as soon as they switch Wi-Fi hotspot on.

    The fact is that in non-dense areas (rural, sub-urban or even general built-up areas), operators do not have to worry about the network being overloaded and can use their licensed spectrum. Nobody is planning to deploy LTE-U / LAA in these areas. In dense and ultra-dense areas, there are many users, many Wi-Fi access points, ad-hoc Wi-Fi networks and many other sources of interference. In theory LTE-U / LAA can help significantly but as there are many sources of interference,its uncertain if it would be a win-win for everyone or just more interference for everyone to deal with.

    Further reading:


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    Its been nearly 2 years since I last blogged about ETSI Security workshop. A lot has changed since then, especially as 5G is already in the process of being standardised. This is in addition to NFV / SDN that also applied to 4G networks.

    ETSI Security Week (12 - 16 June) covered lot more than 5G, NFV, SDN, etc. Security specialists can follow the link to get all the details (if they were not already aware of).

    I want to quickly provide 3 links so people can find all the useful information:

    NFV Security Tutorialdesigned to educate attendees on security concerns facing operators and providers as they move forward with implementing NFV. While the topics are focused on security and are technical in nature we believe any individual responsible for designing, implementing or operating a NFV system in an organization will benefit from this session. Slides here.

    NFV Security: Network Functions Virtualization (NFV), leveraging cloud computing, is set to radically change the architecture, security, and implementation of telecommunications networks globally. The NFV Security day will have a sharp focus on the NFV security and will bring together the world-wide community of the NFV security leaders from the industry, academia, and regulators. If you want to meet the movers and shakers in this field, get a clear understanding of the NFV security problems, challenges, opportunities, and the state of the art development of security solutions, this day is for you. Slides here.



    5G Security: The objectives of this event are to:
    • Gather different actors involved in the development of 5G, not only telecom, and discuss together how all their views will shape together in order to understand the challenges, threats and the security requirements that the 5G scenarios will be bringing.
    • Give an update of what is happening in:
      • 5G security research: Lot of research is on-going on 5G security and several projects exist on the topic.
      • 5G security standards: Standardization bodies have already started working 5G security and their work progress will be reviewed. Also any gap or additional standardization requirements will be discussed.
      • Verticals and business (non-technical) 5G security requirements: 5G is playground where different verticals besides the telecom industry is playing a role and their requirements will be key for the design of 5G security. In addition 5G is where "security" will become the business driver.
    • Debate about hot topics such as: IoT security, Advances in lightweight cryptography, Slicing security. Privacy. Secure storage and processing. Security of the interconnection network (DIAMETER security). Relevance of Quantum Safe Cryptography for 5G, Authorization concepts....
    Slides for 5G Security here.

    In addition, Jaya Baloo, CISO, KPN Telecom talks about 5G network security at TechXLR8 2017. Embedded is a video of that:



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    I came across this interesting article in WSJ, courtesy of the Benedict Evans newsletter, which discusses how Indians are using their smartphones even more and consuming far more data than they previously did. Due to low incomes, spending money on mobile top-up is to the detriment of other sectors. To quote the article:
    “There was a time when kids would come here and blow their pocket money on chips and chocolate,” said Anup Kapoor, who runs a mom-and-pop grocery shop in New Delhi. These days, “they spend every last rupee on a data recharge instead.”

    United Nations have created 17 very ambitious Sustainable Development Goals (SDGs) that universally apply to all, countries will mobilize efforts to end all forms of poverty, fight inequalities and tackle climate change, while ensuring that no one is left behind.
    The SDGs, also known as Global Goals, build on the success of the Millennium Development Goals (MDGs) and aim to go further to end all forms of poverty. The new Goals are unique in that they call for action by all countries, poor, rich and middle-income to promote prosperity while protecting the planet. They recognize that ending poverty must go hand-in-hand with strategies that build economic growth and addresses a range of social needs including education, health, social protection, and job opportunities, while tackling climate change and environmental protection.
    I have talked about Rural connectivity on this blog and a lot more on small cells blog. In fact the heart touching end user story from Rural England was shared multiple times on different platforms. GSMA has done a good amount of work with the rural communities with their mobile for development team and have some interesting videos showing positive impacts of bringing connectivity to rural communities in Tanzania (see here and here).

    While you will always hear about the challenges in bringing connectivity to these rural communities, all technological challenges can be solved. There are many highly ambitious projects using balloons, drones, creating droneways, Helikites, Satellite backhaul, drone based backhaul, mmWave backhaul, etc. The real problem to solve here are the costs (spectrum, infrastructure, etc.) and the end-user pricing.

    Coming back to the first story of this post about India, when given an option about selecting mobile data or shampoo, people will probably choose mobile data. What about mobile data vs food? While there are some innovative young companies that can help bring the costs down, there is still a big hurdle to leap in terms of convincing the operators mindsets, bureaucracy, etc.

    To help explain my point lets look at an excerpt from this article in Wired:
    It’s the kind of problem that Vanu Bose, the founder of the small cell network provider CoverageCo, has been trying to solve with a new, ultra-energy-efficient mobile technology. Bose chose two places to pilot this tech: Vermont and Rwanda. “We picked these two locations because we knew they would be challenging in terrain and population density,” he says. “What we didn’t expect was that many of the problems were the same in Rwanda and Vermont—and in fact the rollout has been much easier in Africa.
    The good news is that things are changing. Parallel Wireless (see disclosure at the bottom) is one such company trying to simplify network deployment and at the same time bring the costs down. In a recent deployment with Ice Wireless in Canada, this was one of the benefit to the operator. To quote from MobileSyrup:
    A radio access network is one of the key components in the architecture of any wireless network. RANs sit between consumer-facing devices like smartphones and computers and the core network, helping connect those devices to the larger network.  
    Essentially where the likes of Nokia and Huawei ask clients to buy an expensive hardware component for their RAN needs, Parallel Wireless offers allows companies like Ice Wireless to use off-the-shelf computer and server components to emulate a RAN. The company also sells wireless base stations like the two pictured above that are smaller than the average cell tower one sees in cities and less remote parts of the country.  
    Besides reducing the overall price of a network deployment, Parallel’s components present several other advantages for a company like Ice Wireless.  
    For instance, small base stations make it easier for the company to build redundancies into its network, something that’s especially important when a single arctic snowstorm can knock out wireless service for thousands of people.
    These kind of benefits allow operators to pass on the cost reduction thereby allowing the price reduction for end users. In case of Ice Wireless, they have already got rid of roaming charges and have started offering unlimited data plans for the communities in Canada's North.

    Finally, to quote David Nabarro, Special Adviser of the United Nations Secretary-General on the 2030 Agenda for Sustainable Development from the GSMA 2016 Mobile Industry Impact Report: Sustainable Development Goals:
    Achieving the SDGs demands new technologies, innovations, and data collection that can integrate and complement traditional statistics. A driving force behind this data revolution is mobile technology. 
    Mobile phone technology has already transformed societies around the globe, even the poorest countries and communities. It is helping to empower women, create jobs, spur financial independence, improve education, boost agriculture production, and promote better health. Mobile phones have enabled communities to monitor elections, hold governments accountable, and save lives in natural disasters. 
    As we focus on implementing the Sustainable Development Goals, the mobile industry has a critical role in working with governments and the international community to expand connectivity, to lower barriers to access, and to ensure that tools and applications are developed with vulnerable communities in mind. 

    With 5G just round the corner, I hope that the operators and vendors will be able to get their costs down, resulting in lower end-user prices. That would be a win-win for everyone.

    *Full Disclosure: I work for Parallel Wireless as a Senior Director, Strategic Marketing. This blog is maintained in my personal capacity and expresses my own views, not the views of my employer or anyone else. Anyone who knows me well would know this.

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    A recent AT&T blog post looks at how the fake cactus antennas are manufactured. I also took a closeup of a fake cactus antenna when I went to a Cambridge Wireless Heritage SIG event as can be seen in tweet below.

    The blog says:
    To make a stealth site look as real as possible, our teams use several layers of putty and paint. Our goal is to get the texture and color just right, but also ensure it can withstand natural elements – from snowy Colorado to blistering Arizona. 
    Tower production takes 6-8 weeks and starts with constructing a particular mold. The molds quickly become 30-foot tall saguaro cacti or 80-foot tall redwood trees.But these aren’t just steel giants. 
    The materials that cover the stealth antennas, like paint or faux-leaves, must be radio frequency-friendly. Stealth antennas designed to look like church steeples or water towers are mostly made of fiberglass. This lets the signal from the antennas penetrate through the casing. 
    These stealth deployments are just one of the many unique ways we provide coverage to our customers. So take a look outside, your connection may be closer than you think—hidden in plain sight!
    This videos gives a good idea


    If this is a topic of interest, then have a look at this collection of around 100 antennas:



    See also:




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    IMSI Catchers can be a real threat. It doesn't generally affect anyone unless someone is out to get them. Nevertheless its a security flaw that is even present in LTE. This presentation here is a good starting point on learning about IMSI Catcher and the one here about privacy and availability attacks.


    This article by Ericsson is a good starting point on how 5G will enhance security by IMSI encryption. From the article:
    The concept we propose builds on an old idea that the mobile device encrypts its IMSI using home network’s asymmetric key before it is transmitted over the air-interface. By using probabilistic asymmetric encryption scheme – one that uses randomness – the same IMSI encrypted multiple times results in different values of encrypted IMSIs. This makes it infeasible for an active or passive attacker over the air-interface to identify the subscriber. Above is a simplified illustration of how a mobile device encrypts its IMSI. 
    Each mobile operator (called the ‘home network’ here) has a public/private pair of asymmetric keys. The home network’s private asymmetric key is kept secret by the home network, while the home network’s public asymmetric key is pre-provisioned in mobile devices along with subscriber-specific IMSIs (Step 0). Note that the home network’s public asymmetric key is not subscriber-specific. 
    For every encryption, the mobile device generates a fresh pair of its own public/private asymmetric keys (Step 1). This key pair is used only once, hence called ephemeral, and therefore provide probabilistic property to the encryption scheme. As shown in the figure, the mobile device then generates a new key (Step 2), e.g., using Diffie–Hellman key exchange. This new key is also ephemeral and is used only once to encrypt the mobile device’s IMSI (Step 3) using symmetric algorithm like AES. The use of asymmetric and symmetric crypto primitives as described above is commonly known as integrated/hybrid encryption scheme. The Elliptic Curve Integrated Encryption Scheme (ECIES) is a popular scheme of such kind and is very suitable to the use case of IMSI encryption because of low impact on radio bandwidth and mobile device’s battery. 
    The nicest thing about the described concept is that no public key infrastructure is necessary, which significantly reduces deployment complexity, meaning that mobile operators can start deploying IMSI encryption for their subscribers without having to rely on any external party or other mobile operators.

    '3GPP TR 33.899: Study on the security aspects of the next generation system' lists one such approach.


    The Key steps are as follows:

    1. UE is configured with 5G (e)UICC with ‘K’ key, the Home Network ID, and its associated public key.
    2. SEAF send Identity Request message to NG-UE. NG-UE considers this as an indication to initiate Initial Authentication.
    3. NG-UE performs the following:
      1. Request the (e)UICC application to generate required security material for initial authentication, RANDUE, , COUNTER, KIARenc, and KIARInt.
      2. NG-UE builds IAR as per MASA. In this step NG-UE includes NG-UE Security Capabilities inside the IAR message. It also may include its IMEI. 
      3. NG-UE encrypts the whole IAR including the MAC with the home network public key.
      4. NG-UE sends IAR to SEAF.
    4. Optionally, gNB-CP node adds its Security Capabilities to the transposrt message between the gNB-CP and the SEAF (e.g., inside S1AP message as per 4G).
    5. gNB-CP sends the respective S1AP message that carries the NG-UE IAR message to the SEAF.
    6. SEAF acquirs the gNB-CP security capabilities as per the listed options in clause 5.2.4.12.4.3and save them as part of the temporary context for the NG-UE.
    7. SEAF follows MASA and forward the Authentication and Data Request message to the AUSF/ARPF.
    8. When AUSF/ARPF receives the Authentication and Data Request message, authenticates the NG-UE as per MASA and generates the IAS respective keys. AUSF/ARPF may recover the NG-UE IMSI and validate the NG-UE security capabilities.
    9. AUSF/ARPF sends Authentication and Data Response to the SEAF as per MASA with NG-UE Security Capabilities included.
    10. SEAF recovers the Subscriber IMSI, UE security Capabilities, IAS keys, RANDHN, COUNTER and does the following:
      1. Examine the UE Security Capabilities and decides on the Security parameters.
      2. SEAF may acquire the UP-GW security capabilities at this point after receiving the UP-GW identity from AUSF/ARPF or allocate it dynamically through provisioning and load balancing.
    11. SEAF builds IAS and send to the NG-UE following MASA. In addition, SEAF include the gNB-CP protocol agreed upon security parameters in the S1AP message being sent to the gNB-CP node.
    12. gNB-CP recovers gNB-CP protocol agreed upon security parameters and save it as part of the NG-UE current context.
    13. gNB-CP forwards the IAS message to the NG-UE.
    14. NG-UE validates the authenticity of the IAS and authenticates the network as per MASA. In addition, the UE saves all protocols agreed upon security parameters as part of its context. NG-UE sends the Security and Authentication Complete message to the SEAF.
    15. SEAF communicates the agreed upon UP-GW security parameters to the UP-GW during the NG-UE bearer setup.

    ARPF - Authentication Credential Repository and Processing Function 
    AUSF - Authentication Server Function 
    SCMF - Security Context Management Function
    SEAF - Security Anchor Function
    NG-UE - NG UE
    UP - User Plane 
    CP - Control Plane
    IAR - Initial Authentication Request 
    IAS - Initial Authentication Response
    gNB - Next Generation NodeB

    You may also want to refer to the 5G Network Architecture presentation by Andy Sutton for details.

    See also:


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  • 08/27/17--09:31: Bluetooth 5 for IoT

  • Bluetooth 5 (not 5.0 - to simplify marketing messages and communication) was released last year. The main features being 2x Faster, 4x Range (Bluetooth 4 - 50m outdoors, 10m Indoors; Bluetooth 5 - 200m outdoors, 40m indoors) & 8x Data.
    I like this above slide by Robin Heydon, Qualcomm from a presentation he gave in CW (Cambridge Wireless) earlier this year. What is highlights is that Bluetooth 5 is Low Energy (LE) like its predecessor 4.0.For anyone interested, a good comparison of 5 vs 4.2 is available here.

    In addition, Mesh support is now available for Bluetooth. I assume that this will work with Bluetooth 4.0 onwards but it would probably only make sense from Bluetooth 5 due to support for reasonable range.

    The Bluetooth blog has a few posts on Mesh (see here, here and here). I like this simple introductory video below.


    This recent article by Geoff Varral on RTT says the following (picture from another source):

    Long distance Bluetooth can also be extended with the newly supported mesh protocol.

    This brings Bluetooth into direct competition with a number of other radio systems including 802.15,4 based protocols such as Zigbee, LoRa, Wireless-M (for meter reading), Thread and 6 LowPAN (IPV6 over local area networks. 802.11 also has a mesh protocol and long distance ambitions including 802.11ah Wi-Fi in the 900 MHz ISM band. It also moves Bluetooth into the application space targeted by LTE NB IOT and LTE M though with range limitations.

    There are some interesting design challenges implied by 5.0. The BLE specification is inherently less resilient to interference than Classic or EDR Bluetooth. This is because the legacy seventy eight X 1 MHz channels within the 20 MHz 2.4 GHz pass band are replaced with thirty nine two MHz channels with three fixed non hopping advertising channels in the middle and edge of the pass band.

    These have to withstand high power 20 MHz LTE TDD in Band 40 (below the 2.4 GHz pass band) and high power 20 MHz LTE TDD in band 41 above the pass band (and Band 7 LTE FDD). This includes 26 dBm high power user equipment.

    The coexistence of Bluetooth, Wi-Fi and LTE has been intensively studied and worked on for over ten years and is now managed with surprising effectiveness within a smart phone through a combination of optimised analogue and digital filtering (SAW and FBAR filters) and time domain interference mitigation based on a set of  industry standard wireless coexistence protocols.

    The introduction of high power Bluetooth however implies that this is no longer just a colocation issue but potentially a close location issue. Even managing Bluetooth to Bluetooth coexistence becomes a non-trivial task when you consider that +20 dBm transmissions will be closely proximate to -20 dBm or whisper mode -30 dBm transmissions and RX sensitivity of -93 dBm, potentially a dynamic range of 120dB. Though Bluetooth is a TDD system this isolation requirement will be challenging and vulnerable to ISI distortion. 

    More broadly there is a need to consider how ‘5G Bluetooth’ couples technically and commercially with 5G including 5G IOT

    Ericsson has a whitepaper on Bluetooth Mesh Networking. The conclusion of that agrees that Bluetooth may become a relevant player in IoT:

    Bluetooth mesh is a scalable, short-range IoT technology that provides flexible and robust performance. The Bluetooth Mesh Profile is an essential addition to the Bluetooth ecosystem that enhances the applicability of Bluetooth technology to a wide range of new IoT use cases. Considering the large Bluetooth footprint, it has the potential to be quickly adopted by the market. 

    With proper deployment and configuration of relevant parameters of the protocol stack, Bluetooth mesh is able to support the operation of dense networks with thousands of devices. The building automation use case presented in this white paper shows that Bluetooth mesh can live up to high expectations and provide the necessary robustness and service ratio. Furthermore, the network design of Bluetooth mesh is flexible enough to handle the introduction of managed operations on top of flooding, to further optimize behavior and automate the relay selection process.


    Moreover, another Ericsson article says that "smartphones with built-in Bluetooth support can be part of the mesh, may be used to configure devices and act as capillary gateways."

    A capillary network is a LAN that uses short-range radio-access technologies to provide groups of devices with wide area connectivity. Capillary networks therefore extend the range of the wide area mobile networks to constraint devices. Figure above illustrates the Bluetooth capillary gateway concept.

    Once there are enough smartphones and Bluetooth devices with Bluetooth 5 and Mesh support, It would be interesting to see how developers use it. Would also be interesting to see if it will start encroaching LoRa and Sigfox markets as well.

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    Picture Source: Cnet

    Bell Labs, which has played a significant role in telecoms history and has a very glorious list of achievements created a collection of short films highlighting the brilliant minds who created the invisible nervous system of our society. Some of you may be aware that Bell Labs is now a part of Nokia but was previously part of Alcatel-Lucent, Lucent and AT&T before that.

    The playlist with 5 videos is embedded below and short details of the videos follows that.


    Video 1: Introduction

    Introducing 'Future Impossible', a collection of short films highlighting the brilliant minds who created the invisible nervous system of our society, a fantastic intelligent network of wires and cables undergirding and infiltrating every aspect of modern life.


    Video 2: The Shannon Limit

    In 1948, father of communications theory Claude Shannon developed the law that dictated just how much information could ever be communicated down any path, anywhere, using any technology. The maximum rate of this transmission would come to be known as the Shannon Limit.  Researchers have spent the following decades trying to achieve this limit and to try to go beyond it.


    Video 3: The Many Lives of Copper

    In the rush to find the next generation of optical communications, much of our attention has moved away from that old standby, copper cabling. But we already have miles and miles of the stuff under our feet and over our heads. What if instead of laying down new optical fiber cable everywhere, we could figure out a way to breathe new life into copper and drive the digital future that way?


    Video 4: The Network of You

    In the future, every human will be connected to every other human on the planet by a wireless network. But that’s just the beginning. 

    Soon the stuff of modern life will all be part of the network, and it will unlock infinite opportunities for new ways of talking, making and being. The network will be our sixth sense, connecting us to our digital lives. In this film, we ponder that existence and how it is enabled by inventions and technologies developed over the past 30 years, and the innovations that still lie ahead of us.


    Video 5: Story of Light

    When Alexander Graham Bell discovered that sound could be carried by light, he never could have imagined the millions of written text and audio and video communications that would one day be transmitted around the world every second on a single strand of fiber with the dimensions of a human hair.

    Follow the journey of a single text message zipping around the globe at the speed of light, then meet the researchers that have taken up Bell’s charge.


    For anyone interested, Wikipedia has a good detailed info on Bell Labs history here.

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    The 5G System architecture (based on 3GPP TS 23.501: System Architecture for the 5G System; Stage 2) consists of the following network functions (NF). The functional description of these network functions is specified in clause 6.
    -Authentication Server Function (AUSF)
    -Core Access and Mobility Management Function (AMF)
    -Data network (DN), e.g. operator services, Internet access or 3rd party services
    -Structured Data Storage network function (SDSF)
    -Unstructured Data Storage network function (UDSF)
    -Network Exposure Function (NEF)
    -NF Repository Function (NRF)
    -Network Slice Selection Function (NSSF)
    -Policy Control function (PCF)
    -Session Management Function (SMF)
    -Unified Data Management (UDM)
    -Unified Data Repository (UDR)
    -User plane Function (UPF)
    -Application Function (AF)
    -User Equipment (UE)
    -(Radio) Access Network ((R)AN)

    As you can see, this is slightly more complex than the 2G/3G/4G Core Network Architecture.

    Alan Carlton, Vice President, InterDigital and Head of InterDigital International Labs Organization spanning Europe and Asia provided a concise summary of the changes in 5G core network in ComputerWorld:

    Session management is all about the establishment, maintenance and tear down of data connections. In 2G and 3G this manifested as the standalone General Packet Radio Service (GPRS). 4G introduced a fully integrated data only system optimized for mobile broadband inside which basic telephony is supported as just one profile.

    Mobility management as the name suggests deals with everything that needs doing to support the movement of users in a mobile network. This encompasses such functions as system registration, location tracking and handover. The principles of these functions have changed relatively little through the generations beyond optimizations to reduce the heavy signaling load they impose on the system.

    The 4G core network’s main function today is to deliver an efficient data pipe. The existence of the service management function as a dedicated entity has been largely surrendered to the “applications” new world order. Session management and mobility management are now the two main functions that provide the raison d’etre for the core network.

    Session management in 4G is all about enabling data connectivity and opening up a tunnel to the world of applications in the internet as quickly as possible. This is enabled by two core network functions, the Serving Gateway (SGW) and Packet Data Gateway (PGW). Mobility management ensures that these data sessions can be maintained as the user moves about the network. Mobility management functions are centralized within a network node referred to as Mobility Management Entity (MME). Services, including voice, are provided as an “app” running on top of this 4G data pipe. The keyword in this mix, however, is “function”. It is useful to highlight that the distinctive nature of the session and mobility management functions enables modularization of these software functions in a manner that they can be easily deployed on any Commercial-Off-The-Shelf (COTS) hardware.

    The biggest change in 5G is perhaps that services will actually be making a bit of a return...the plan is now to deliver the whole Network as a Service. The approach to this being taken in 3GPP is to re-architect the whole core based on a service-oriented architecture approach. This entails breaking everything down into even more detailed functions and sub-functions. The MME is gone but not forgotten. Its former functionality has been redistributed into precise families of mobility and session management network functions. As such, registration, reachability, mobility management and connection management are all now new services offered by a new general network function dubbed Access and Mobility Management Function (AMF). Session establishment and session management, also formerly part of the MME, will now be new services offered by a new network function called the Session Management Function (SMF). Furthermore, packet routing and forwarding functions, currently performed by the SGW and PGW in 4G, will now be realized as services rendered through a new network function called the User Plane Function (UPF).

    The whole point of this new architectural approach is to enable a flexible Network as a Service solution. By standardizing a modularized set of services, this enables deployment on the fly in centralized, distributed or mixed configurations to enable target network configurations for different users. This very act of dynamically chaining together different services is what lies at the very heart of creating the magical network slices that will be so important in 5G to satisfy the diverse user demands expected. The bottom line in all this is that the emphasis is now entirely on software. The physical boxes where these software services are instantiated could be in the cloud or on any targeted COTS hardware in the system. It is this intangibility of physicality that is behind the notion that the core network might disappear in 5G.


    3GPP TS 23.502: Procedures for the 5G System; Stage 2, provides examples of signalling for different scenarios. The MSC above shows the example of registration procedure. If you want a quick refresher of LTE registration procedure, see here.

    I dont plan to expand on this procedure here. Checkout section "4.2.2 Registration Management procedures" in 23.502 for details. There are still a lot of FFS (For further studies😉) in the specs that will get updated in the coming months.


    Further Reading:


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    I have discussed this problem in past, based on questions asked on various fora (example). Here is a video I made some weeks back. Will be interested to know what other reasons people can come up with 😊.



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    Back in 2013, I spoke about Smart Batteries. Still waiting for someone to deliver on that. In the meantime I noticed that you can use an Android phone to charge another phone, via cable though. See the pic below:


    You are probably all aware of the Samsung Galaxy Note 7 catching fires. In case you are interested in knowing the reasons, Guardian has a good summary here. You can also see the pic below that summarises the issue.


    Lithium-ion batteries have always been criticized for its abilities to catch fire (see here and here) but researchers have been working on ways to reduce the risk of fire. There are some promising developments.


    The electrochemical masterminds at Stanford University have created a lithium-ion battery with built-in flame suppression. When the battery reaches a critical temperature (160 degrees Celsius in this case), an integrated flame retardant is released, extinguishing any flames within 0.4 seconds. Importantly, the addition of an integrated flame retardant doesn't reduce the performance of the battery.

    Researchers at the University of Maryland and the US Army Research Laboratory have developed a safe lithium-ion battery that uses a water-salt solution as its electrolyte. Lithium-ion batteries used in smartphones and other devices are typically non-aqueous, as they can reach higher energy levels. Aqueous lithium-ion batteries are safer as the water-based electrolytes are inflammable compared to the highly flammable organic solvents used in their non-aqueous counterparts. The scientists have created a special gel, which keeps water from reacting with graphite or lithium metal and setting off a dangerous chain reaction.


    Bloomberg has a good report as to why we’re going to need more Lithium.

    Starting about two years ago, fears of a lithium shortage almost tripled prices for the metal, to more than $20,000 a ton, in just 10 months. The cause was a spike in the market for electric vehicles, which were suddenly competing with laptops and smartphones for lithium ion batteries. Demand for the metal won’t slacken anytime soon—on the contrary, electric car production is expected to increase more than thirtyfold by 2030, according to Bloomberg New Energy Finance.

    Even if the price of lithium soars 300 percent, battery pack costs would rise only by about 2 percent.

    University of Washington researchers recently demonstrated the world's first battery-free cellphone, created with funding from the U.S. National Science Foundation (NSF) and a Google Faculty Research Award for mobile research.

    The battery-free technology harvests energy from the signal received from the cellular base station (for reception) and the voice of the user (for transmission) using a technique called backscattering. Backscattering for battery-free operation is best known for its use in radio frequency identification (RFID) tags, typically utilized for applications such as locating products in a warehouse and keeping track of high-value equipment. An RFID base station (called a reader) "pings" the tag with an RF pulse, which allows the tag to harvest microwatts of energy from it—enough to return a backscattered RF signal modulated with the identity of the item.



    Unfortunately, harvesting generates very little energy; so little, that you really need a new standard. For instance, Wi-Fi signals transmit continuously, but harvesting that energy constantly will only enable transmissions of about 10 feet today. Range will be the big challenge for making this technology successful.

    So we wont be seeing them anytime soon unfortunately.

    Recycling of materials is always a concern, especially now that the use of Lithium-ion is increasing. Financial Times (FT) recently did a good summary of all the companies trying to recycle Lithium, Cobalt, etc.

    Mr Kochhar estimates over 11m tonnes of spent lithium-ion batteries will be discarded by 2030. The company is looking to process 5,000 tonnes a year to start with and eventually 250,000 tonnes — a similar amount to a processing plant for mined lithium, he said.

    The battery industry currently uses 42 percent of global cobalt production, a critical metal for Lithium-ion cells. The remaining 58 percent is used in diverse industrial and military applications (super alloys, catalysts, magnets, pigments…) that rely exclusively on the material.

    According to Wikipedia, The purpose of the Cobalt (Co) within the LIBs is to act as a sort of bridge for the lithium ions to travel on between the cathode (positive end of the battery) and the anode (the negative end). During the charging of the battery, the cobalt is oxidized from Coᶾ⁺ to Co⁴⁺. This means that the transition metal, cobalt, has lost an electron. During the discharge of the battery the cobalt is reduced from Co⁴⁺ to Coᶾ⁺. Reduction is the opposite of oxidation. It is the gaining of an electron and decreases the overall oxidation state of the compound. Oxidation and reduction reactions are usually coupled together in a series of reactions known as red-ox (reduction-oxidation) reactions. This chemistry was utilized by Sony in 1990 to produce lithium ion cells.

    From Treehugger: An excellent investigative piece by the Washington Post called “The cobalt pipeline: From dangerous tunnels in Congo to consumers’ mobile tech” explores the source of this valuable mineral that everyone relies on, yet knows little about.
    “Lithium-ion batteries were supposed to be different from the dirty, toxic technologies of the past. Lighter and packing more energy than conventional lead-acid batteries, these cobalt-rich batteries are seen as ‘green.’ They are essential to plans for one day moving beyond smog-belching gasoline engines. Already these batteries have defined the world’s tech devices.
    “Smartphones would not fit in pockets without them. Laptops would not fit on laps. Electric vehicles would be impractical. In many ways, the current Silicon Valley gold rush — from mobile devices to driverless cars — is built on the power of lithium-ion batteries.”
    What The Post found is an industry that’s heavily reliant on ‘artisanal miners’ or creuseurs, as they’re called in French. These men do not work for industrial mining firms, but rather dig independently, anywhere they may find minerals, under roads and railways, in backyards, sometimes under their own homes. It is dangerous work that often results in injury, collapsed tunnels, and fires. The miners earn between $2 and $3 per day by selling their haul at a local minerals market.

    There is a big potential for reducing waste and improving lives, hopefully we will see some developments on this front soon.

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    Huawei (see here and here) has partnered with China Telecom and Bike sharing company called Ofo.

    ofo developed an IoT smart lock based on NB-IoT technology that lowers power consumption, enables wide coverage, and slashes system resource delays at low cost. NB-IoT lets ofo ensure it has bikes located at key locations when commuter demand is highest. Meanwhile, bikes can be unlocked in less than a second. Both improvements have greatly boosted user satisfaction.

    ofo and its partners added key technologies to ofo’s own platform. These included the commercial network provided by China Telecom, and Huawei’s intelligent chip-based NB-IoT solution. When launching its NB-IoT solution earlier this year, ofo founder and CEO Dai Wei said that the cooperation between ofo, Huawei, and China Telecom is a “mutually beneficial joint force of three global leading enterprises.”

    At the core is Huawei’s IoT solution, which includes smart chips, networking, and an IoT platform. The solution provides strong coverage in poor-signal areas and a network capacity that’s more than one hundred times stronger than standard terminals. The payment process has dropped from 25 seconds to less than 5, while battery life has been lengthened from 1 or 2 months to more than 2 years, saving costs and reducing the need for frequent maintenance.

    ofo’s cooperation with Huawei on NB-IoT smart locks bodes well for improving the industry as whole. Huawei’s technology optimizes lifecycle management for locks, while the sensors on the locks collect information such as equipment status, user data, and operating data. They connect the front- and back-end industrial chains to achieve intelligent business management, enable the bikes to be located in hot spots, facilitate rapid maintenance, and boost marketing and value-added services.

    This video gives an idea of how this works:



    As per Mobile World Live:

    Ofo co-founder Xue Ding said during a presentation the high power efficiency and huge capacity of NB-IoT make the technology ideal to deliver its smart locks, which are really the brains of its operations.

    The company offers what is termed station free pushbike hire, meaning bikes can be collected and deposited from any legal parking spot. Users can locate bikes using their smartphone, and unlock it by scanning a barcode.

    However, the process can be interrupted by mobile network congestion or if signals are weak – for example in remote areas: “Using NB-IoT, users will not be stuck because of inadequate capacity,” Xue said.
    ...
    Xiang Huangmei, a VP at China Telecom’s Beijing branch, said the low power consumption of the NB-IoT chip in the lock means the battery will last eight years to ten years, so it will never need to be replaced during the standard lifecycle of an Ofo bike.

    The NB-IoT network, deployed on the 800MHz band, offers good indoor and outdoor coverage, the VP said citing car parks as an example. One base station can support 100,000 devices over an area of 2.5 square-km.

    Finally, to know which operator is supporting which IoT technology, see the IoT tracker here.

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    I recently did a 4G voice presentation for beginners after realizing that even though so many years have passed after VoLTE was launched, people are still unsure how it works or how its different from CS Fallback.

    There are many other posts that discuss these topics in detail on this blog (follow the label) or on 3G4G website. Anyway, here is the video:


    The slides are available on 3G4G Slideshare account here. More similar training videos are available here.

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