Sunday 12 March 2017

High Power / Performance User Equipment (#HPUE)

3GPP refers to HPUE as High Power UE while the US operator Sprint prefers to use the term High Performance UE.

HPUE was initially defined for US Public Safety Band 14 (700MHz). The intention was that this high power UEs can increase the coverage range from 4km to 8km. This would mean larger coverage areas and less number of cells.

While the commercial UE's (class 3) transmit at +23dBm (max 200mW), the Public Safety people intend to use class 1 UE transmitting +31 dBm (max 1.25W). It was felt that this feature could be beneficial for some TDD bands that do not have to worry about backward compatibility. One such band, pushed by Sprint was TDD Band 41 (2500MHz). As this band is for the commercial UE's, instead of class 1, class 2 power at +26dBm (max 400mW) was proposed.

3GPP TS 36.886 provides the following justification:

Currently, 3GPP has defined only Power Class UE 3 as the type of UE supported for TDD LTE band 41 operations. This definition was based on aligning TDD LTE Band 41 UE power classes with prior work in 3GPP related to other bands. However, it should be mentioned that 3GPP UE Power Class 3 definition (i.e. 23dBm) was mainly driven to ensure backward compatibility with prior technologies (i.e. GSM/UMTS) [2] so that network deployment topologies remain similar. Furthermore, maintaining the same power class UE definition (i.e. Class 3) as previous technologies would maintaining compliance with various national regulatory rulings, particularly in terms of SAR, for FDD LTE duplexing mode. 

However, TDD LTE band 41 does not have any 3GPP legacy technologies associated with it, hence the backward compatibility consideration is not applicable in its case. Also, since band 41 is defined as a TDD LTE band, it is less susceptible to SAR levels that FDD LTE bands due to SAR definition. Therefore, defining a new UE power class with higher than 23dBm Tx power for TDD LTE Band 41 operations would not compromise any of 3GPP foundational work, while improving UE and network performance. It should also be mentioned that 3GPP has done similar work on other bands (i.e. band 14) when defining a higher power class UE, hence the concept presented in this document is a continuation of that process.

The present document carries out a feasibility analysis for defining a UE Power class 2 (i.e. 26dBm) for operation on TDD LTE band 41. The document analyses current and future technological advancements in the area of UE RF front-end components and architectures that enable such definition while maintaining 3GPP specification and other regulatory bodies' requirements. It should be emphasized that this proposal only relates to single carrier UL operations on TDD band 41 (i.e. TM-1/2 modes) without affecting current 3GPP definition for UL carrier aggregation on band 41.

As you can see from the tweet above, Sprint CEO is quite pleased with the HPUE. 

SourceDiana Goovaerts

Iain Gillott, iGR points out that HPUE applies to Sprint’s 2.5 GHz TDD network and associated spectrum, and the company claims up to 30 percent increase in cell cover from the new technology.  It should be noted that HPUE is a 3GPP standard that applies to the 2.5 GHz TDD band (Band 41) and is also to be used by China Mobile and Softbank.  HPUE was developed as part of the Global TDD LTE Initiative (GTI) which includes Qualcomm Technologies, Samsung, ZTE, Broadcom, MediaTek, Skyworks Solutions, Alcatel, Motorola, LG and Qorvo... The cool part: the improvement in coverage comes from simply improving the device uplink power.  So Sprint, China Mobile and Softbank will not have to visit their cell sites to make changes; they just need 2.5 GHz TDD devices with HPUE to get the benefit.


Milan Milanović recently wrote about Sprint’s Gigabit Class LTE network goes live in New Orleans. One of the questions I had was why is the uplink so rubbish as compared to downlink. He kindly pointed out to me that this is TDD config 2
If you are wondering what is TDD Config 2, see the pic below
Source: ShareTechNote

Sprint expects HPUE to appear in postpaid devices starting in 2017, including new devices from Samsung, LG, HTC, and Moto. It’s expected that all of Sprint’s new devices will have HPUE support within the next two years.

I think it would be interesting to see how this impacts when there are a lot more users and devices. I am quite sure there will be more requests for HPUE in further TDD bands.

Related Links:

Monday 6 March 2017

IMT-2020 (5G) Requirements


ITU has just agreed on key 5G performance requirements for IMT-2020. A new draft report ITU-R M.[IMT-2020.TECH PERF REQ] is expected to be finally approved by  ITU-R Study Group 5 at its next meeting in November 2017. The press release says "5G mobile systems to provide lightning speed, ultra-reliable communications for broadband and IoT"


The following is from the ITU draft report:

The key minimum technical performance requirements defined in this document are for the purpose of consistent definition, specification, and evaluation of the candidate IMT-2020 radio interface technologies (RITs)/Set of radio interface technologies (SRIT) in conjunction with the development of ITU-R Recommendations and Reports, such as the detailed specifications of IMT-2020. The intent of these requirements is to ensure that IMT-2020 technologies are able to fulfil the objectives of IMT-2020 and to set a specific level of performance that each proposed RIT/SRIT needs to achieve in order to be considered by ITU-R for IMT-2020.


Peak data rate: Peak data rate is the maximum achievable data rate under ideal conditions (in bit/s), which is the received data bits assuming error-free conditions assignable to a single mobile station, when all assignable radio resources for the corresponding link direction are utilized (i.e., excluding radio resources that are used for physical layer synchronization, reference signals or pilots, guard bands and guard times). 

This requirement is defined for the purpose of evaluation in the eMBB usage scenario. 
The minimum requirements for peak data rate are as follows:
Downlink peak data rate is 20 Gbit/s.
Uplink peak data rate is 10 Gbit/s.


Peak spectral efficiency: Peak spectral efficiency is the maximum data rate under ideal conditions normalised by channel bandwidth (in bit/s/Hz), where the maximum data rate is the received data bits assuming error-free conditions assignable to a single mobile station, when all assignable radio resources for the corresponding link direction are utilized (i.e. excluding radio resources that are used for physical layer synchronization, reference signals or pilots, guard bands and guard times).

This requirement is defined for the purpose of evaluation in the eMBB usage scenario.
The minimum requirements for peak spectral efficiencies are as follows: 
Downlink peak spectral efficiency is 30 bit/s/Hz.
Uplink peak spectral efficiency is 15 bit/s/Hz.


User experienced data rate: User experienced data rate is the 5% point of the cumulative distribution function (CDF) of the user throughput. User throughput (during active time) is defined as the number of correctly received bits, i.e. the number of bits contained in the service data units (SDUs) delivered to Layer 3, over a certain period of time.

This requirement is defined for the purpose of evaluation in the related eMBB test environment.
The target values for the user experienced data rate are as follows in the Dense Urban – eMBB test environment: 
Downlink user experienced data rate is 100 Mbit/s
Uplink user experienced data rate is 50 Mbit/s


5th percentile user spectral efficiency: The 5th percentile user spectral efficiency is the 5% point of the CDF of the normalized user throughput. The normalized user throughput is defined as the number of correctly received bits, i.e., the number of bits contained in the SDUs delivered to Layer 3, over a certain period of time, divided by the channel bandwidth and is measured in bit/s/Hz. 

This requirement is defined for the purpose of evaluation in the eMBB usage scenario.
Indoor Hotspot – eMBB - Downlink: 0.3 bit/s/Hz Uplink: 0.21 bit/s/Hz
Dense Urban – eMBB - Downlink: 0.225 bit/s/Hz Uplink: 0.15 bit/s/Hz
Rural – eMBB - Downlink: 0.12 bit/s/Hz Uplink: 0.045 bit/s/Hz


Average spectral efficiency: Average spectral efficiency  is the aggregate throughput of all users (the number of correctly received bits, i.e. the number of bits contained in the SDUs delivered to Layer 3, over a certain period of time) divided by the channel bandwidth of a specific band divided by the number of TRxPs and is measured in bit/s/Hz/TRxP.

This requirement is defined for the purpose of evaluation in the eMBB usage scenario.
Indoor Hotspot – eMBB - Downlink: 9 bit/s/Hz/TRxP Uplink: 6.75 bit/s/Hz/TRxP
Dense Urban – eMBB - Downlink: 7.8 bit/s/Hz/TRxP Uplink: 5.4 bit/s/Hz/TRxP
Rural – eMBB - Downlink: 3.3 bit/s/Hz/TRxP Uplink: 1.6 bit/s/Hz/TRxP


Area traffic capacity: Area traffic capacity is the total traffic throughput served per geographic area (in Mbit/s/m2). The throughput is the number of correctly received bits, i.e. the number of bits contained in the SDUs delivered to Layer 3, over a certain period of time.

This requirement is defined for the purpose of evaluation in the related eMBB test environment.
The target value for Area traffic capacity in downlink is 10 Mbit/s/m2 in the Indoor Hotspot – eMBB test environment.


User plane latency: User plane latency is the contribution of the radio network to the time from when the source sends a packet to when the destination receives it (in ms). It is defined as the one-way time it takes to successfully deliver an application layer packet/message from the radio protocol layer 2/3 SDU ingress point to the radio protocol layer 2/3 SDU egress point of the radio interface in either uplink or downlink in the network for a given service in unloaded conditions, assuming the mobile station is in the active state. 
This requirement is defined for the purpose of evaluation in the eMBB and URLLC usage scenarios.
The minimum requirements for user plane latency are
4 ms for eMBB
1 ms for URLLC 
assuming unloaded conditions (i.e., a single user) for small IP packets (e.g., 0 byte payload + IP header), for both downlink and uplink.


Control plane latency: Control plane latency refers to the transition time from a most “battery efficient” state (e.g. Idle state) to the start of continuous data transfer (e.g. Active state).
This requirement is defined for the purpose of evaluation in the eMBB and URLLC usage scenarios.
The minimum requirement for control plane latency is 20 ms. Proponents are encouraged to consider lower control plane latency, e.g. 10 ms.


Connection density: Connection density is the total number of devices fulfilling a specific quality of service (QoS) per unit area (per km2).

This requirement is defined for the purpose of evaluation in the mMTC usage scenario.
The minimum requirement for connection density is 1 000 000 devices per km2.


Energy efficiency: Network energy efficiency is the capability of a RIT/SRIT to minimize the radio access network energy consumption in relation to the traffic capacity provided. Device energy efficiency is the capability of the RIT/SRIT to minimize the power consumed by the device modem in relation to the traffic characteristics. 
Energy efficiency of the network and the device can relate to the support for the following two aspects:
a) Efficient data transmission in a loaded case;
b) Low energy consumption when there is no data.
Efficient data transmission in a loaded case is demonstrated by the average spectral efficiency 

This requirement is defined for the purpose of evaluation in the eMBB usage scenario.
The RIT/SRIT shall have the capability to support a high sleep ratio and long sleep duration. Proponents are encouraged to describe other mechanisms of the RIT/SRIT that improve the support of energy efficient operation for both network and device.


Reliability: Reliability relates to the capability of transmitting a given amount of traffic within a predetermined time duration with high success probability

This requirement is defined for the purpose of evaluation in the URLLC usage scenario. 
The minimum requirement for the reliability is 1-10-5 success probability of transmitting a layer 2 PDU (protocol data unit) of 32 bytes within 1 ms in channel quality of coverage edge for the Urban Macro-URLLC test environment, assuming small application data (e.g. 20 bytes application data + protocol overhead). 
Proponents are encouraged to consider larger packet sizes, e.g. layer 2 PDU size of up to 100 bytes.


Mobility: Mobility is the maximum mobile station speed at which a defined QoS can be achieved (in km/h).

The following classes of mobility are defined:
Stationary: 0 km/h
Pedestrian: 0 km/h to 10 km/h
Vehicular: 10 km/h to 120 km/h
High speed vehicular: 120 km/h to 500 km/h

Mobility classes supported:
Indoor Hotspot – eMBB: Stationary, Pedestrian
Dense Urban – eMBB: Stationary, Pedestrian, Vehicular (up to 30 km/h)
Rural – eMBB: Pedestrian, Vehicular, High speed vehicular 


Mobility interruption time: Mobility interruption time is the shortest time duration supported by the system during which a user terminal cannot exchange user plane packets with any base station during transitions.

This requirement is defined for the purpose of evaluation in the eMBB and URLLC usage scenarios.
The minimum requirement for mobility interruption time is 0 ms.


Bandwidth: Bandwidth is the maximum aggregated system bandwidth. The bandwidth may be supported by single or multiple radio frequency (RF) carriers. The bandwidth capability of the RIT/SRIT is defined for the purpose of IMT-2020 evaluation.

The requirement for bandwidth is at least 100 MHz
The RIT/SRIT shall support bandwidths up to 1 GHz for operation in higher frequency bands (e.g. above 6 GHz). 

In case you missed, a 5G logo has also been released by 3GPP


Related posts:



Friday 24 February 2017

Connecting Rural Scotland using Airmasts and Droneways


This week EE has finally done a press release on what they term as Airmasts (see my blog post here). Back in Nov. last year, Mansoor Hanif, Director of Converged Networks and Innovation BT/EE gave an excellent presentation on connecting rural Scottish Islands using Airmasts and Droneways at the Facebook TIP Summit. Embedded below are the slides and video from that talk.





In other related news, AT&T is showing flying COWs (Cell On Wheels) that can transmit LTE signals


Their innovation blog says:

It is designed to beam LTE coverage from the sky to customers on the ground during disasters or big events.
...
Here’s how it works. The drone we tested carries a small cell and antennas. It’s connected to the ground by a thin tether. The tether between the drone and the ground provides a highly secure data connection via fiber and supplies power to the Flying COW, which allows for unlimited flight time.  The Flying COW then uses satellite to transport texts, calls, and data. The Flying COW can operate in extremely remote areas and where wired or wireless infrastructure is not immediately available. Like any drone that we deploy, pilots will monitor and operate the device during use.

Once airborne, the Flying COW provides LTE coverage from the sky to a designated area on the ground.  

Compared to a traditional COW, in certain circumstances, a Flying COW can be easier to deploy due to its small size. We expect it to provide coverage to a larger footprint because it can potentially fly at altitudes over 300 feet— about 500% higher than a traditional COW mast.  

Once operational, the Flying COW could eventually provide coverage to an area up to 40 square miles—about the size of a 100 football fields. We may also deploy multiple Flying COWs to expand the coverage footprint.

Nokia on the other hand has also been showcasing drones and LTE connectivity for public safety at D4G Award event in Dubai


Nokia's Ultra Compact Network provides a standalone LTE network to quickly re-establish connectivity to various mission-critical applications including video-equipped drones. Drones can stream video and other sensor data in real time from the disaster site to a control center, providing inputs such as exact locations where people are stranded and nature of the difficulty of reaching the locations.

Related Posts:



Friday 17 February 2017

What's '5G' in one word for you?


Last month in the IET 'Towards 5G Mobile Technology – Vision to Reality' seminar, Dr. Mike Short threw out a challenge to all speakers to come up with one word to describe 5G technology. The speakers came up with the following 'one words':
  • Professor Mischa Dohler, Centre for Telecommunications Research, King's College London, UK - Skills
  • Professor Maziar Nekovee, Professor,University of Sussex UK - Transformative or Magic
  • Professor Andy Sutton, Principal Network Architect, BT, UK - Opportunity
  • Professor Mark Beach, University of Bristol, UK - Networked-Society
  • Mark Barrett, CMO, Bluwireless, UK - Gigabit
  • Dr Nishanth Sastry, Centre for Telecommunications Research, Kings’ College London, UK - Flexibility or Efficiency
  • Dr Reiner Hoppe, Developer Electromagnetic Solutions, Altair - Radio
  • Professor Klaus Moessner, 5G Innovation Centre, University of Surrey, UK - Capacity
  • Joe Butler, Director of Technology, Ofcom, UK - Ubiquity
  • Dr Deeph Chana, Deputy Director, Institute for Security Science and Technology, Imperial College London, UK - Accessibility
What is your one word to describe 5G? Please add in comments. I welcome critical suggestions too :-)

Anyway, for anyone interested, the following story summarises the event:

This section contained story from Storify. Storify was shut down on May 16, 2018 and as a result the story was lost. An archived version of the story can be seen on wayback machine here.

Related links:

Sunday 5 February 2017

An Introduction to IoT: Connectivity & Case Studies


I did an introductory presentation on IoT yesterday at at the University of Northampton, Internet of Things event. Below if my presentation in full. Can be downloaded from slideshare.



xoxoxoxoxoxo Added 18/02/2017 oxoxoxoxoxoxox

Below is video of the presentation above and post presentation interview:

Wednesday 1 February 2017

5G Network Architecture and Design Update - Jan 2017

Andy Sutton, Principal Network Architect at BT recently talked about the architecture update from the Dec 2016 3GPP meeting. The slides and the video is embedded below.





You can see all the presentations from IET event 'Towards 5G Mobile Technology – Vision to Reality' here.

Eiko Seidel recently also wrote an update from 3GPP 5G Adhoc regarding RAN Internal Functional Split. You can read that report here.

Related posts:

Thursday 26 January 2017

3GPP Rel-14 IoT Enhancements


A presentation (embedded below) by 3GPP RAN3 Chairman - Philippe Reininger - at the IoT Business & Technologies Congress (November 30, in Singapore). Main topics are eMTC, NB-IOT and EC-GSM-IoT as completed in 3GPP Release 13 and enhanced in Release 14. Thanks to Eiko Seidel for sharing the presentation.


Sunday 22 January 2017

Augmented / Virtual Reality Requirements for 5G


Ever wondered whether 5G would be good enough for Augmented and Virtual Reality or will we need to wait for 6G? Some researchers are trying to identify the AR / VR requirements, challenges from a mobile network point of view and possible options to solve these challenges. They have recently published a research paper on this topic.

Here is a summary of some of the interesting things I found in this paper:

  • Humans process nearly 5.2 gigabits per second of sound and light.
  • Without moving the head, our eyes can mechanically shift across a field of view of at least 150 degrees horizontally (i.e., 30:000 pixels) and 120 degrees vertically (i.e., 24:000 pixels).
  • The human eye can perceive much faster motion (150 frames per second). For sports, games, science and other high-speed immersive experiences, video rates of 60 or even 120 frames per second are needed to avoid motion blur and disorientation.
  • 5.2 gigabits per second of network throughput (if not more) is needed.
  • At today’s 4K resolution, 30 frames per second and 24 bits per pixel, and using a 300 : 1 compression ratio, yields 300 megabits per second of imagery. That is more than 10x the typical requirement for a high-quality 4K movie experience.
  • 5G network architectures are being designed to move the post-processing at the network edge so that processors at the edge and the client display devices (VR goggles, smart TVs, tablets and phones) carry out advanced image processing to stitch camera feeds into dramatic effects.
  • In order to tackle these grand challenges, the 5G network architecture (radio access network (RAN), Edge and Core) will need to be much smarter than ever before by adaptively and dynamically making use of concepts such as software defined networking (SDN), network function virtualization (NFV) and network slicing, to mention a few facilitating a more flexible allocating resources (resource blocks (RBs), access point, storage, memory, computing, etc.) to meet these demands.
  • Immersive technology will require massive improvements in terms of bandwidth, latency and reliablility. Current remotereality prototype requires 100-to-200Mbps for a one-way immersive experience. While MirrorSys uses a single 8K, estimates about photo-realistic VR will require two 16K x 16K screens (one to each eye).
  • Latency is the other big issue in addition to reliability. With an augmented reality headset, for example, real-life visual and auditory information has to be taken in through the camera and sent to the fog/cloud for processing, with digital information sent back to be precisely overlaid onto the real-world environment, and all this has to happen in less time than it takes for humans to start noticing lag (no more than 13ms). Factoring in the much needed high reliability criteria on top of these bandwidth and delay requirements clearly indicates the need for interactions between several research disciplines.


These key research directions and scientific challenges are summarized in Fig. 3 (above), and discussed in the paper. I advice you to read it here.

Related posts:

Monday 16 January 2017

Gigabit LTE?


Last year Qualcomm announced the X16 LTE modem that was capable of up to 1Gbps, category 16 in DL and Cat 13 (150 Mbps) in UL. See my last post on UE categories here.


Early January, it announced Snapdragon 835 at CES that looks impressive. Android central says "On the connectivity side of things, there's the Snapdragon X16 LTE modem, which enables Category 16 LTE download speeds that go up to one gigabit per second. For uploads, there's a Category 13 modem that lets you upload at 150MB/sec. For Wi-Fi, Qualcomm is offering an integrated 2x2 802.11ac Wave-2 solution along with an 802.11ad multi-gigabit Wi-Fi module that tops out at 4.6Gb/sec. The 835 will consume up to 60% less power while on Wi-Fi."

Technology purists would know that LTE, which is widely referred to as 4G, was in fact pre-4G or as some preferred to call it, 3.9G. New UE categories were introduced in Rel-10 to make LTE into LTE-Advanced with top speeds of 3Gbps. This way, the ITU requirements for a technology to be considered 4G (IMT-Advanced) was satisfied.


LTE-A was already Gigabit capable in theory but in practice we had been seeing peak speeds of up to 600Mbps until recently. With this off my chest, lets look at what announcements are being made. Before that, you may want to revisit what 4.5G or LTE-Advanced Pro is here.

  • Qualcomm, Telstra, Ericsson and NETGEAR Announce World’s First Gigabit Class LTE Mobile Device and Gigabit-Ready Network. Gigabit Class LTE download speeds are achieved through a combination of 3x carrier aggregation, 4x4 MIMO on two aggregated carriers plus 2x2 MIMO on the third carrier, and 256-QAM higher order modulation. 
  • TIM in Italy is the first in Europe to launch 4.5G up to 500 Mbps in Rome, Palermo and Sanremo
  • Telenet in partnership with ZTE have achieved a download speed of 1.3 Gbps during a demonstration of the ZTE 4.5G new technology. That's four times faster than 4G's maximum download speed. Telenet is the first in Europe to reach this speed in real-life circumstances. 4.5G ZTE technology uses 4x4 MIMO beaming, 3-carrier aggregation, and a QAM 256 modulation.
  • AT&T said, "The continued deployment of our 4G LTE-Advanced network remains essential to laying the foundation for our evolution to 5G. In fact, we expect to begin reaching peak theoretical speeds of up to 1 Gbps at some cell sites in 2017. We will continue to densify our wireless network this year through the deployment of small cells and the use of technologies like carrier aggregation, which increases peak data speeds. We’re currently deploying three-way carrier aggregation in select areas, and plan to introduce four-way carrier aggregation as well as LTE-License Assisted Access (LAA) this year."
  • T-Mobile USA nearly reached a Gigabit and here is what they say, "we reached nearly 1 Gbps (979 Mbps) on our LTE network in our lab thanks to a combination of three carrier aggregation, 4x4 MIMO and 256 QAM (and an un-released handset)."
  • The other US operator Sprint expects to unveil some of its work with 256-QAM and massive MIMO on Sprint’s licensed spectrum that pushes the 1 gbps speed boundary. It’s unclear whether this will include an actual deployment of the technology

So we are going to see a lot of higher speed LTE this year and yes we can call it Gigabit LTE but lets not forget that the criteria for a technology to be real '4G' was that it should be able to do 1Gbps in both DL and UL. Sadly, the UL part is still not going Gigabit anytime soon.

Saturday 7 January 2017

New LTE UE Categories (Downlink & Uplink) in Release-13

Just noticed that the LTE UE Categories have been updated since I last posted here. Since Release-12 onwards, we now have a possibility of separate Downlink (ue-CategoryDL) and Uplink (ue-CategoryUL) categories.

From the latest RRC specifications, we can see that now there are two new fields that can be present ue-CategoryDL and ue-CategoryUL.

An example defined here is as follows:

Example of RRC signalling for the highest combination
UE-EUTRA-Capability
   ue-Category = 4
      ue-Category-v1020 = 7
         ue-Category-v1170 = 10
            ue-Category-v11a0 = 12
               ue-CategoryDL-r12 = 12
               ue-CategoryUL-r12 = 13
                  ue-CategoryDL-v1260 = 16

From the RRC Specs:

  • The field ue-CategoryDL is set to values m1, 0, 6, 7, 9 to 19 in this version of the specification.
  • The field ue-CategoryUL is set to values m1, 0, 3, 5, 7, 8, 13 or 14 in this version of the specification.

3GPP TS 36.306 section 4 provides much more details on these UE categories and their values. I am adding these pictures from the LG space website.



More info: