Sunday, March 19, 2017

Latest on 5G Spectrum - March 2017

In an earlier post I mentioned that there will be three different types of spectrum that would be needed for 5G; coverage layer, capacity layer and high throughput layer. There is now a consensus within the industry for this approach.


In a 5G seminar, back in Jan, there were a few speakers who felt that there is an informal agreement about the frequencies that will be used. One such slide from Ofcom could be seen in the picture above. Ofcom has also recently released a report expanding on this further.


Analysys Mason has nicely summarized the bands suggested by Ofcom and possibly available in the UK for 5G in the picture above.

Global mobile Suppliers Association (GSA) has also nicely summarised the bands under investigations and trials as follows:

Coverage Layer600 MHz, 700 MHz, 800 MHz, 900 MHz, 1.5 GHz, 2.1 GHz, 2.3 GHz and 2.6 GHz

Capacity Layer:

Europe                     3400 – 3800 MHz (awarding trial licenses)

China                       3300 – 3600 MHz (ongoing trial), 4400 – 4500 MHz, 4800 – 4990 MHz

Japan                       3600 – 4200 MHz and 4400-4900 MHz

Korea                       3400 – 3700 MHz

USA                          3100 – 3550 MHz (and 3700 – 4200 MHz)

High Throughput Layer:

USA:      27.5 – 28.35 GHz and 37 – 40 GHz pre-commercial deployments in 2018

Korea:   26.5 – 29.5 GHz trials in 2018 and commercial deployments in 2019

Japan:   27.5 – 28.28 GHz trials planned from 2017 and potentially commercial deployments in 2020

China:    Focusing on 24.25 – 27.5 GHz and 37 – 43.5 GHz studies

Sweden: 26.5 – 27.5 GHz awarding trial licenses for use in 2018 and onwards

EU:        24.25 – 27.5 GHz for commercial deployments from 2020

Finally, as a reminder, list of bands originally approved for IMT-2020 (5G) as follows:


Another potential band, not being mentioned above is the 66-76GHz spectrum. This band is adjacent to the 60 GHz Wi-Fi (57 GHz - 66 GHz). Lessons learned from that band can be applied to the 5G band too.

Related links:



Thursday, March 16, 2017

Satellite Industry is Gearing up for The Next Revolution in Communications

Intelsat graphic
Source: Intelsat
I have been talking about the role of satellites in future communications on my blog and various industry fora. While most of the telecom industry is focused on 5G, it’s good to see that the satellite industry is getting ready for the next revolution.

Source: New York Times
Masayoshi Son, chief executive of SoftBank has made it his mission to merge satellite operators Intelsat and OneWeb. While on the surface they may seem as competitors, in reality they complement each other. Intelsat operates geostationary (GEO) satellites while OneWeb is building low earth orbit (LEO) satellites. They both serve overlapping but different purposes and it makes sense for them to work together. LEO satellites which are roughly at 1200km have far lower latency than compared to GEO satellites that are 36,000km away. On the other hand LEO satellites do not appear stationary unlike GEO satellites.

We in CW are already aware of Masayoshi Son’s ambition and vision. Last year Softbank acquired ARM for approximately £24 billion. In a recent keynote delivered at the Mobile World Congress 2017 (#MWC17), Son explained his vision and reasoning for this purchase. In fact he mentioned that he has a 30 year vision which is why he thinks ‘cell towers from space’ are the next step in evolution. While he refers to them as fiber from the space, I wouldn’t go that far in comparison but do admit they have the potential to deliver high speed connectivity anywhere on earth.

The most obvious application of high speed connectivity ubiquitously available anywhere on earth are connected cars. While there is Wi-Fi to provide connectivity and software updates when parked at home, it will be complemented by mobile connectivity within the cities and the major roads. What is missing is anywhere and everywhere connectivity that the satellites can bring.

The big barrier for satellite connectivity in the cars had been the need for satellite dish mounted on the top of a car roof. Kymeta, an innovative company based in Washington, USA has been trying for years to solve this problem. In May, they will start selling  their “lightweight flat-panel antennas, meant to bring fast satellite-transmitted internet connections to cars, trains and boats”.

Source: Seattle Times
Kymeta is partnering with Toyota and Intelsat to bring a complete solution for future connectivity in the cars. They are not the only ones, there are other similar interesting projects ongoing in many different parts of the world.


The telecom industry cannot ignore satellite communications forever. Satellites have already proved themselves beyond doubt in broadcasting, navigation, earth observation, etc. It’s just a matter of time before they prove their while in communications as well.

Originally Posted on CW Blog here.

Sunday, March 12, 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, March 6, 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


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