3GPP Activities on ITS March, 2016 SungDuck CHUN LG Electronics
1. History Overall Timeline 3GPP started feasibility study of 3GPP support of V2X communication from 1Q 2015 Discussion started from 3GPP RAN in 2Q 2014, and RAN sent request to define service requirement to SA1 in 4Q 2014. First SI/WI for V2X was created in 1Q 2015 at SA1 and completed in 4Q 2015. Technical Report for V2X (TR 22.885) was approved in 4Q 2015. Technical specification for V2X (TS 22.185) has been sent for SA approval in 1Q 2016. First stage-3 level TS for V2X will be available in 3Q 2016. SA SA1 SI approval SA1 WI approval SA1 SI completion SA1 WI completion 15.02 15.09 15.12 16.03 RAN First discussion on LTE V2X RAN SI approval RAN WI on D2D-based V2V approval RAN SI completion & WI for other V2X aspects may start RAN WI on D2D-based V2V completion 14.06 15.06 15.12 16.06 16.09 2
1. History Detailed Target Schedule The ongoing progress for release 14 in Working Groups SA1, SA2, SA3, RAN1, RAN2, RAN3 and RAN4. SI approval SI completion WI Approval WI completion SA1 (Stage-1) 15.03 15.09 15.12 16.03 SA2 (Stage-2) 16.06 Estimate Estimate SA3 16.09 RAN Overall (Stage-3) RAN1 V2X SI 15.06 D2D-based V2V 15.12 V2X SI Estimate 16.06 16.09 D2D-based V2V RAN2 RAN3 16.03 RAN4 17.03 Study Item/TR Work Item/ TS 3
2. Scope General Standardization activity for V2X in 3GPP includes the transport layer aspects, but does not include V2X application-layer aspects. In overview section of TS 22.185: These intelligent transportation services and the associated message sets have been defined in automotive SDOs outside 3GPP. Three basic classes of applications for providing ITS services: road safety, traffic efficiency, and other applications can be found in e.g., [3]. 3GPP only handles the transport of these messages to support different types of V2X applications. The message transport expectations are described in requirements defined in this specification. The related references and the related SDOs: ETSI TR 102 638 V1.1.1: "Intelligent Transport Systems (ITS); Vehicular Communications; Basic Set of Applications; Definitions". ETSI TS 102 637-1 V1.1.1, "Intelligent Transport Systems (ITS); Vehicular Communications; Basic Set of Applications; Part 1: Functional Requirements GSMA Connected Living, ETSI ITS (Intelligent Transportation System), US SAE, C-ITS project in Korean Ministry of Land, Infrastructure and Transport, IEEE, SAE-China, C- ITS, WWRF, C2C-CC, ACEA, ERTICO, ACEM, etc 4
2. Scope Types The following four types of V2X are considered: V2V: Vehicle-to-Vehicle V2P: Vehicle-to-Pedestrian (e.g., handheld terminal carried by a pedestrian, cyclist, driver or passenger) V2I: Vehicle-to-Infrastructure application, where infrastructure is RSU (Roadside Unit). RSU is a transportation infrastructure entity implemented in an enb or a stationary UE V2N: Vehicle-to-Network, where Network means application service/server which is out of 3GPP scope To support these V2X applications, 3GPP considers both WAN based communication and D2D (device-to-device) direct communication. 5
2. Scope RSUs In 3GPP, RSU is: A stationary infrastructure entity supporting V2X applications that can exchange messages with other entities supporting V2X applications. RSU is a logical entity that combines V2X application logic with the functionality of an enb (referred to as enb-type RSU) or UE (referred to as UE-type RSU). UE-type RSU is beneficial in areas where cellular coverage cannot be provided (e.g. deep in the mountain area). The following figures show the possible example of RSU implementations. UE-type RSU enb-type RSU RSU V2X Application UE A (Vehicle) V5 PC5 RSU V2X Application UE B (Stationary) V2X Application UE A (Vehicle) V1 Uu V2X Application L-GW enb 6
2. Scope Per WG objective/scope For V2X, the respective WGs are working on the following aspects: SA1 Specify service requirements for transport layer support of V2X communication, for both safety-related and non-safety aspects. SA SA2 Specify enhancment to existing 3GPP architecture and functionalities to support V2X 3GPP SA3 RAN1 Identify secuirty requirement for V2X, and specify enhancement to existing 3GPP security functionalities to support the requirements. Specify enhancment to physical layer structure, procedures (e.g. resource allocation, synchronization, etc) RAN RAN2 RAN3 Specify enhancment to radio protocols and RRC Signalling. Specifiy mechanisms to e.g. spectum access control, switching between interfaces PC5/Uu Specify enhancment to radio access network protocol RAN4 Specify UE RF TX/RX requirements up to 6 Ghz and RRM/ demodulation requirements Evaluation for adjacent coexistence at licensed/unlicensed band 7
3. Enablers 3GPP did not begin standardization work for V2X from scratch, but fully utilizes and enhances the existing framework as much as possible: This will expedite the standardization processof V2X communication in 3GPP The following enablers/functions are mainly considered for the bases of V2X: MBMS (Multimedia Broadcast Multicast Service) 3GPP functionality to provide efficient delivery of broadcast and multicast services. This functionality can be used for various purposes such as group call session, live TV broadcasting, public warning message delivery, etc. ProSe (Proximity-based services) or D2D (Device to Device) communication: D2D communications refers to the communications of users in cellular networks without base station (BS) intervention or with reduced BS intervention. MBMS ProSE WAN UE1 UE1 UE2 UE1 UE2 D2D UE3 8
4. Work Status SA1 Service Requirement Following the completion of the feasibility study (LTE support of V2X services), Technical Report 22.885 was published in December 2015 Technical specification 22.185 will include service requirements of 3GPP transport service for V2X application. Upon the approval by 3GPP SA Plenary in Mar.2016, TS 22.185 will be available at ftp://ftp.3gpp.org/specs/archive/22_series/22.185/ In TS 22.185, service requirements are classified as follow: Specific Req. Overall Req. Security Req. Latency/ Reliability Message Size Frequency Range Speed Configurability/ Inter-PLMN/ Prioritization/ Area control. etc Max 100ms latency for V2V/P/I, Max 1000ms latency for V2N 50~300 bytes for periodic, 1200 bytes for event-triggered (except security) Support up to 10 messages transfer per second per UE Support communication range sufficient to give driver ample response time (4 second) Support Max relative velocity up to 280 km/h, absolute velocity 160 km/h Authorization / Anonimity / Integrity protection / Privacy 9
4. Work Status SA2 Architecture SA2 has made two architectual assumption on PC5-based and embms-based V2X, respectively. The architectural assumption for PC5 based V2X: V2X Control Function: the logical function used for network related actions for V2X V5 V2X Control Function PLMN B... V2X Control Function PLMN n V2X Application V2X Application V2 UE B (Vehicle) V2 UE C (pedestrian) PC5 V3 V2X Application Server V2 V2X Control Function PLMN A V3 V5 PC5 V3 V4 HSS S6a S1 E-UTRAN UE A (Vehicle) LTE-Uu V2X Application MME S/P-GW LTE-Uu V3 V2X Application UE D (stationary) PC5 V5 The latest TR 23.785 developed by SA2 is available at ftp://ftp.3gpp.org/specs/archive/23_series/23.785/ Figure 4.1.1-1: Reference architecture for V2X (PC5 based) 10 V1
4. Work Status SA2 Architecture The following architectural assumption for embms-based V2X: V2X AS (Application Server): the logical function that is used for network related actions required for V2X. Based on the following key issues identified, SA2 is working on solutions: Service Authorization V2X message transmission/reception for V2V and V2P Policy/Parameter provisioning for V2V/V2P/V2I V2X message prioritization for V2V / V2P V2X message transmission/reception for Vehicle and RSU for V2I Latency improvement for embms for V2X QoS for V2X 11
4. Work Status SA3 Security As of Febuary 2016, SA3 identified three key issues to resolve and some resulting requirements for the security in 3GPP support of V2X: V2X communication security The transmission of data between different entities should be integrity protected. The transmission of data between different entities should be protected from replays. UE pseudo-anonymity should be provided to conceal personal data from attackers Authorization for LTE-V2X radio resources If many malicious UEs may attempt to request radio resources at the same time from the MNO network, it would lead to an exhaustion of network radio resources. Legal vehicle UEs can not get available radio resourcers for LTE-V2X communications. V2X Entities secure environment The attacker may manipulate the information from measuring instruments, generating false V2X messages/ warnings which may mislead surrounding V2X entities to take wrong actions and possibly cause accidents. The attacker may manipulate the data processing in V2X entities, leading to false V2X messages The attacker may modify the security materials or vital configuration data in enb-type RSU The latest TR33.885 is available at ftp://ftp.3gpp.org/specs/archive/33_series/33.885/ 12
4. Work Status RAN1 Physical Layer RAN1 has finished evaluation of performance for PC5 based V2V communication: Simulation results shows that PC5 interface transport for V2V communication is feasible and can meet requirements Study result is avaialble at ftp://ftp.3gpp.org/specs/archive/36_series/36.885/ Based on this, RAN1 is working on PC5 interface enhancement in areas such as: Enhancement to PC5 interface resource allocation (resource pool, selection, etc) Enhancement to physical layer structures such as DMRS (Demodulation Reference Symblol) to handle high doppler Synchronization procedure (i.g. source of synchronization such as GNSS, enb, etc) Progress will be made on other than PC5-based V2V: Possibility of extending PC5 design for V2V to V2I/V2P communication Enhancements to MBMS for Uu based V2V/I/P communication Enhancements to physical layer structure or procedure for Uu based V2V/I/P 13
4. Work Status RAN2 L2/L3 RAN2 has mainly focused on evaluation of latency and capacity for V2V service: Latency requirement can be met for PC5-based V2V communication with relevant resource configuration. Latency requirement can be met for Uu-based V2V communication only in limited cases which could demand almost 100% of the resources for V2V services e.g. when short UL/DL scheduling periods are configured for all Ues in Urban scenario. Given that we cannot assume that 100% of the resources are available for V2V services, some UL enhancements can be considered. Unicast based mechanism is not suitable to meet DL capacity requirement. Focus will be on enhancement based on broadcast mechanism. RAN2 will do further enhancement study on following areas: UL SPS enhancement based on traffic characteristic Latency improvement on DL broadcast DL broadcast on the basis of UE geographical location Support for the inter-operator deployment QoS support for Uu based or PC5 based mechanism 14
4. Work Status RAN3 Radio Access Network RAN3 formally started work on V2X from 1Q 2016. It made progress by agreeing following way forward: For the D2D based V2X WI, confirms that only V2V over PC5 is supported and RSU is not discussed. Following is captured in TR 36.885: Local breakout architecture (i.e, putting V2X application closer to the edge of Radio Network edge) is considered to better fulfil the stringenet V2X latency requirements V2x server, connected through SIPTO@LN with stand-alone GW V2x server, connected through SIPTO@LN with co-located L-GW V2x server co-located in the enb The small and variable areas in V2X could be managed via MBSFN and/or SC-PTM Localized MBMS should be considered. MBSFN SC-PTM 15
4. Work Status RAN4 RF RAN4 started work on V2X from 1Q 2016. It made progress by agreeing following way forward: Define operating band for PC5 based V2V: For licensed band, current commercially available band willl be considerd. For unlicensed band, band 46 reuse or new band will be considered. Coexistence scenario and simulation parameter in adjacent channel: Licensed band (Aggressor-to-Victim): V2V UE-to-LTE enb and LTE UE-to-V2V UE in 2GHz band Unlicensed band (Aggressor-to-Victim): FFS, consider V2V-to-LAA or V2V-to-ITS for legacy system protection 16
5. Performance Benefit Potential benefit of LTE-based V2X is: Existing LTE infrastructure can be reused. Reduces the cost for V2I/N deployment and maintenance Controls and authorizes V2X devices via infrastructure Not only for WAN but also for D2D Various operation scenarios are possible especially using RSUs For example, cellular links can be used as backup of D2D link Larger coverage is provided. High transmit power and antenna height of base stations in WAN-based solutions. FDM of transmissions from multiple UEs within a carrier to increase the multiplexing capacity Use of multiple antennas, turbo code. Carrier frequency, numerology, and sensitivity of LTE. A better multi-carrier/channel operation can be provided. Sharper out-band emission property which reduces interference to adjacent carriers. Efficient operation based on the LTE carrier aggregation framework Services can be optimized for pedestrian UEs. It is expected that pedestrian UE is always equipped with LTE. Battery saving based on LTE power saving mechanism 17
5. Performance Comparision between Uu / PC5 PC5-based V2X Better to meet End-to-end latency Some safety services (e.g. pre-crash warning) requires very tight latency which Uu-based V2X can not meet without potential enhancement. Multi-hop operation using UL + DL might be difficult to meet the requirements with no enhancement. Support operation even when outside of network coverage 100% WAN coverage cannot be guaranteed and is challenging even with current cellular deployment. The safety services should be provided regardless of vehicle location Uu-based V2X Easy to use various cellular network features/merits such as: Attractive for V2I/N services which requires long range communication due to better coverage than PC5-based mechanism (e.g. high power and antenna height of enb can be utilized) Intereference coordination Can provide V2X communication even for UE without D2D capability Can minimize UE implementation cost. Better battery performance for Pedestrian UE * PC5 is the interface used for D2D type communication, Uu is the interface for WAN (Wide Area Network) type communication. 18
6. Operational consideration Spectrum V2X operations under consideration in 3GPP Scenario 1: Multiple operators share V2X spectrum Scenario 2: Multiple operators manage different V2X spectrum Scenario 3: There is only one operator in a region. Scenario 4: There is no network coverage in a region. D2D is the only option for this scenario. Spectrum for WAN (Operator 1) Spectrum for WAN (Operator 1) Spectrum for WAN (Operator 2) Spectrum for WAN (Operator 2) Can be the same spectrum Spectrum Spectrum for D2D (Operator 1&2) Spectrum for D2D (Operator 1) Can be the same spectrum Scenario 1 Coverage Spectrum Spectrum for D2D (Operator 2) Spectrum for WAN (Operator 1) Scenario 2 Coverage Can be the same spectrum Spectrum Spectrum for D2D (Operator 1) Spectrum for D2D Scenario 3 Coverage Scenario 4 19
6. Operational consideration Deploy V2X operations under consideration in 3GPP E-UTRAN E-UTRAN UL DL SL Scenario 1: Only D2D Scenario 2: Only WAN E-UTRAN E-UTRAN SL UL UE (RSU) DL SL DL UE (RSU) UL Scenario 3: Combination of D2D and WAN 20
7. Forward Looking Overall Further enhancement on 3GPP support for V2X will be likely to start in 2Q 2016: Work on 5G communication system started in 3GPP 2Q 2015. In SA1, use case scenario and service requirements for 5G system are being studied. Due to area overlap between 5G study item and Rel-14 V2X study item, study on the support of V2X & Connected Car in 5G has been suspended and will resume in 2Q 2016. Candidate topics are: Further 3GPP enhancement to support autonomous driving Further 3GPP enhancement to support car platooning Inter-3GPP RAT interworking to support communication between UEs of different RATs Etc. 21
7. Forward Looking 5G target 5G performance will be evolution of 4G performance. Enhanced Mobile Broadband Peak Data Rate [Gbps] User Experienced Data Rate [Mbps] Gigabytes in a second Smart Home/Building 3D video, UHD screens Work and play in the cloud Augmented reality Industry automation Area Traffic Capacity [Mbps/m 2 ] 10 20 100 IMT-2020 1 0.1 10 1x Spectrum Efficiency 3x Smart City Voice Massive Machine Type Communications Future IMT Mission critical application, e.g. e-health Self Driving Car Ultra-reliable and Low Latency Communications 100x Network Energy Efficiency 1x 10 6 Connection Density [#/km 2 ] IMT-Adv. 10 5 10 1 350 Latency [ms] 500 Mobility [km/h] IMT2020 Use Cases IMT2020 Key Capabilities 22
7. Forward Looking 5G target Performance evolution as a result of 5G will benefit V2X / Connected car. Thus, evolution of V2X technologies will be continued in 3GPP New air interface can be optimized for V2X communication from the beginning. Lower latency & Higher reliability Higher data rate Characteristics of vehicles can be defined as a new device type Large volume, Sufficient power, More antennas, etc. 23