5g R17 standard is frozen. What does it say?

Reprinted from ： Cyber mercenaries

Beijing time. 6 month 9 On Tuesday night 10 Zero 4 branch ,3GPP stay RAN The first 96 It was announced at the meeting that 5G R17 Standard freezing . It means ,5G In the first half （R15、R16、R17） The standard of has been completed , Entering the second half 5G-Advanced（R18、R19、R20）.

that R17 Mainly about something ？

The spectrum range is extended to 71GHz

as everyone knows ,5G NR Spectrum range （FR） It is divided into FR1 and FR2, among FR1 by 410MHz - 7.125GHz,FR2 by 24.25GHz – 52.6GHz. Now? ,R17 take 5G NR The frequency band ranges from 52.6GHz Extended to 71GHz.

This is related to ITU The frequency band division rhythm is consistent , It's just 11 month , ITU World radiocommunication conference (WRC-19) by 5G More frequency bands have been identified , Include 24.25~27.5GHz、37~43.5GHz、45.5~47GHz、47.2~48.2GHz and 66~71GHz.

RedCap coming

Everybody knows ,NB-IoT and eMTC It's a simplified version 、 Lightweight version LTE, For low power consumption 、 Low cost 、 Low speed rate 、 Large connectivity and wide coverage of Internet of things applications . Get into 5G The age of interconnection , It also needs a simplified version 、 Lightweight version 5G NR, He is RedCap, namely Reduced Capability.

Why RedCap Well ？

5G Defined eMBB、uRLLC and mMTC Three scenes ,eMBB Mainly aimed at 4K/8K、VR/AR And so on ,uRLLC Mainly for remote robot control 、 Automatic driving and other ultra-high reliability and ultra-low delay applications , and NB-IoT and eMTC Will evolve into mMTC, Mainly for low rate large-scale Internet of things connection .

Simple speak ,uRLLC Aiming at “ High-end ” Internet of things application scenarios , and mMTC Aiming at “ Low-end ” Internet of things application scenarios , So here's the problem , stay eMBB、mMTC And uRLLC Between the existence of “ Mid tier IOT market ” Who will solve the blank area ？

For example 5G Take intelligent manufacturing as an example , Only robots control 、AI Quality check and other applications need the network capability of ultra large bandwidth and ultra-low delay , And for the surveillance cameras in the factory 、 For a large number of sensors , Very large bandwidth and very low latency may be a waste , and NB-IoT/eMTC It can't meet the demand in terms of delay and bandwidth capability .

This blank space is RedCap Where it comes in handy .

R17 In version 5G RedCap The key function of ：

• Reduce device complexity , So as to reduce the equipment cost

• Improve power consumption

• The data transmission rate shall not be lower than LTE Cat-1 standard

R17 In version 5G RedCap Standard use cases for ：

• Industrial sensor ： Pressure sensor 、 humidity sensor 、 thermometer 、 Motion sensor 、 Accelerometers and actuators

• Surveillance cameras ： Smart city 、 Factories and other industrial sites

• Wearable device ： Intelligent Watch 、 Electronic health related equipment and medical monitoring equipment

NB-IoT and eMTC It's all over the world

remember ,5G My dream is that all things are connected , It's full connection 、 Full coverage . But it's too hard to realize that dream , Operators have to spend a lot of money , Build a lot of base stations , Especially in remote mountainous areas , The high cost of building a station scares people to death , There's almost no income yet . Even if it's not bad for money , Ships on the sea 、 Airplanes flying in the air , How do you cover ？

The best way is to have a cellular network on the ground “ Tongtian ”, That is to say, with the non ground network （NTN）, Such as satellite network convergence , Create a three-dimensional wide coverage .

3GPP R16 It's been studied 5G NR Integration with off the ground networks ,R17 Version further studies NB-IoT/eMTC Integration with off the ground networks , To support agriculture in remote mountainous areas 、 mining 、 Forestry , And the Internet of things applications in vertical industries such as marine transportation .

NR Coverage enhancement

NB-IoT/eMTC Enhanced coverage , It can improve the coverage of the cellular Internet of things . But all along , Global rural areas eMBB Applications have been ignored . According to statistics , Nearly half of the world's population cannot connect to the Internet , How to fill this digital divide ？ meanwhile ,5G The frequency band is getting higher and higher , The coverage of a single station is getting smaller and smaller , Network coverage expansion is becoming more and more difficult .

So ,R17 Assessed 5G NR Performance of low frequency range of heavy tillage 、 Coverage of uplink and downlink physical channels , Put forward PUSCH、PUCCH、Msg3 Coverage enhancement .

Positioning accuracy is improved to centimeter level

Satellite positioning can't be used indoors ,LTE and WiFi Positioning technology is not accurate , So ,5G stay R16 Positioning function has been added to the version , The use of MIMO Multi beam characteristics , The signal round-trip time based on cell is defined （RTT）、 Signal arrival time difference （TDOA）、 Angle of arrival measurement （AoA）、 Departure angle measurement （AoD） And other indoor positioning technologies , The positioning accuracy can reach 3-10 rice .

But this positioning accuracy is not enough for some industrial Internet of things applications , Such as indoor asset tracking 、AGV Tracking, etc , So ,R17 Further improve the indoor positioning accuracy to centimeter level , Probably 20-30 Cm or so . This is for 5G Enabling the industrial Internet of things is very important .

XR assessment

XR It's extended reality , These include AR、VR and MR（ Mixed reality ）.5G Edge computing makes computing in the cloud 、 Storage capacity and content are closer to the user side , Make the network delay lower , The user experience is more extreme , Can make AR、VR and MR And so on . meanwhile , Thanks to the 5G Low latency 、 Big bandwidth capability , The computing power on the terminal side can also be moved up to the edge cloud , bring VR Helmets and other devices are lighter 、 More power saving 、 Lower cost . such “ Light terminal + Wide pipes + Marginal cloud ” The pattern will be cut down VR/AR The threshold of expensive terminals , Get out of the wire , To promote XR Application popularization .

R17 This edge cloud is evaluated + Distributed architecture of lightweight terminal , And optimize the network delay 、 Processing power and power consumption, etc .

NR Multicast and broadcast services

Remember 4G The times ？3GPP stay R9 The version defines eMBMS, Also known as LTE radio broadcast （LTE Broadcast）. adopt eMBMS, The network can broadcast the same content to multiple mobile phones in the cell .

eMBMS Supported business use cases include mobile TV live broadcast 、 video on demand （ Content preloading ）、 Advertising push 、 Car entertainment 、 Public safety, etc . at that time , One is called “Venue casting” The use case of is widely favored by the industry , It is mainly used in sports events 、 Live scenes such as concerts .

Take the live broadcast of the world's hottest football game as an example , Operators can use eMBMS At the same time, one-way broadcast video streams to the terminal devices of many viewers , To improve the efficiency of network resources , Allow users to watch high-quality live broadcasts anytime, anywhere ; meanwhile , Operators can also pre load and cache content 、 Mass customized advertising, etc , Let users watch the live broadcast while , It can also play back content in real time on demand 、 Watch the game from multiple angles , And online video shopping and gambling .

▲Venue casting Use cases

Later in 2017 year ,3GPP stay R14 The version has been further enhanced eMBMS function , Launched enTV（ Enhanced TV ）, This time, it systematically defines how to broadcast digital TV content through mobile communication network .

but 5G NR Multicast and broadcast services are not yet supported , Before R16 Just research and supplement based on LTE Of 5G Terrestrial broadcasting , So this time R17 Research and definition based on 5G NR Multicast and broadcast services .

This time NR Multicast and broadcast services are mainly aimed at public security multicast and Venue casting scene . Take public security multicast as an example , In case of emergency , It can enable a large number of users in a specific location to receive warnings or notifications at the same time .

INACTIVE Small packet transmission in state

Its full name is NR small data transmissions in INACTIVE state.

as everyone knows ,4G LTE Of RRC There are only two states ：RRC_IDLE and RRC_CONNECTED,5G NR Introduce more RRC_INACTIVE.

stay RRC INACTIVE State, , The terminal is in the sleep state of power saving , But it still retains some RAN Context （ Security context ,UE Ability information, etc ）, Always connected to the network , And it can wake up quickly from RRC INACTIVE The state shifts to RRC CONNECTED state . This reduces signaling overhead , Fast access , Reduce delay , And it can save more power .

Now? R17 Support in INACTIVE In this state, small packets can be transmitted directly , Can minimize power consumption , For some industrial Internet of things applications （ For example, sensor upgrade ） And wechat of smart phones 、Whatsapp And so on chat application is very useful .

NR Sidelink enhance

What is? Sidelink？ It's legendary D2D（ Direct communication between devices ） An enhanced version of , Different from what we know Uplink and Downlink link ,Sidelink It is a new link introduced to support direct communication between devices .

The Internet of vehicles technology is called V2X,Vehicle-to-everything, It means the information interaction between the vehicle and any entity that may affect the vehicle . The car networking technology based on cellular network is called C-V2X, Include LTE V2X and NR V2X.

C-V2X Support vehicles and vehicles 、 Direct communication between vehicle and other equipment and communication based on cellular network , Include V2N（ Vehicles and networks / cloud ）、V2V（ Vehicles and vehicles ）、V2I（ Vehicles and road infrastructure ） and V2P（ Vehicles and pedestrians ） Communication between . among , Vehicles and vehicles 、 Vehicles and other equipment （V2V,V2I） The communication between them adopts PC5 Interface . stay 3GPP Specification ,Sidelink It means passing through PC5 A term used to communicate directly with an interface .

3GPP As early as R13 Version defines PC5 Interface , however , It was just for public safety （PS-LTE） Mission critical requirements , For example, intercom communication in disaster relief . here we are R14 edition ,PC5 Interface extensions apply to LTE V2X technology , That is, based on LTE Systematic V2X service .

Get into 5G Time ,R15 And will be V2X Technical extension support 5G, namely NR V2X.NR V2X added 4G In the era of LTE V2X Solution , It can provide better Internet of vehicles services . It also introduces NR Sidelink, To support vehicles and vehicles 、 Direct communication between vehicle and other equipment such as roadside unit .

And this time NR Sidelink Enhance application scenarios that will communicate directly from V2X Extend to public safety 、 Emergency services , And even direct communication applications between mobile phones . In order to better let Sidelink Support for new applications ,R17 To optimize the Sidelink Power consumption of 、 Spectral efficiency 、 reliability 、 Delay, etc .

IAB enhance

IAB,Integrated Access & Backhaul, It refers to the integration of wireless access and backhaul , It replaces optical fiber forward transmission through wireless return / Comes back , Form a wireless mesh network return topology , So as to avoid laying optical fiber with difficulty in trenching and stringing , Make the base station deployment more flexible 、 Simple 、 Low cost .

R17 Of IAB Enhancements are committed to improving efficiency and supporting a wider range of use cases , For example, make the mesh topology more dynamic , For example, will IAB Applied to communication emergency rescue .

also …

• NR MIMO

Further enhance MIMO Ability , Improve beam shaping and beam management , And reduce related expenses .

• NR DSS enhance

DSS, Dynamic spectrum sharing , stay R16 Great improvements have been made in .R17 Further explore better cross carrier scheduling .

• Further enhance MRDC

MRDC,Multi-Radio Dual Connectivity, This mechanism can quickly reduce the user traffic deactivate Unwanted wireless transmission , This saves electricity .

• NR UE Power Saving Enhancements

5G Terminal power consumption and heating is one of the most concerned problems of users ,R17 Defines further reductions 5G Methods of equipment power consumption .

• Multi-SIM

This is a 3GPP The first study supports double SIM Card or more SIM Card Multi-SIM equipment ,3GPP Will work to improve Multi-SIM technology , For example, one mobile phone supports two SIM card 、 Support different networks without affecting each other .

• other

in addition ,R17 It also studied RAN section 、SON/ Minimize road test data collection enhancements 、 in the light of 5G Different business needs QoE Manage and optimize 、NB-IoT and LTE-MTC Enhancement and other projects .

There are omissions and misunderstandings , Thank you for your comments .

In this paper, the source ： Cyber mercenaries