3GPP TS 36.304 V14.5.0 (2017-12)
`
`Technical Specification
`
`3rd Generation Partnership Project;
`Technical Specification Group Radio Access Network;
`Evolved Universal Terrestrial Radio Access (E-UTRA);
`User Equipment (UE) procedures in idle mode
`(Release 14)
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`The present document has been developed within the 3rd Generation Partnership Project (3GPP TM) and may be further elaborated for the purposes of 3GPP..
`The present document has not been subject to any approval process by the 3GPP Organisational Partners and shall not be implemented.
`This Specification is provided for future development work within 3GPP only. The Organisational Partners accept no liability for any use of this Specification.
`Specifications and reports for implementation of the 3GPP TM system should be obtained via the 3GPP Organisational Partners' Publications Offices.
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`Keywords
`LTE, E-UTRAN, radio, terminal
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`3GPP
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`Copyright Notification
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`No part may be reproduced except as authorized by written permission.
`The copyright and the foregoing restriction extend to reproduction in all media.
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`© 2017, 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC).
`All rights reserved.
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`UMTS™ is a Trade Mark of ETSI registered for the benefit of its members
`3GPP™ is a Trade Mark of ETSI registered for the benefit of its Members and of the 3GPP Organizational Partners
`LTE™ is a Trade Mark of ETSI registered for the benefit of its Members and of the 3GPP Organizational Partners
`GSM® and the GSM logo are registered and owned by the GSM Association
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`Contents
`Foreword....................................................................................................................................... 5
`1
`Scope................................................................................................................................... 6
`2
`References ............................................................................................................................ 6
`3
`Definitions and abbreviations .................................................................................................. 7
`3.1
`Definitions.................................................................................................................................................................. 7
`3.2
`Symbols...................................................................................................................................................................... 9
`3.3
`Abbreviations............................................................................................................................................................. 9
`4
`General description of Idle mode............................................................................................ 10
`4.1
`Overview .................................................................................................................................................................. 10
`4.2
`Functional division between AS and NAS in Idle mode ...................................................................................... 12
`4.3
`Service types in Idle Mode ..................................................................................................................................... 14
`4.4
`NB-IoT functionality in Idle Mode ........................................................................................................................ 15
`5
`Process and procedure descriptions......................................................................................... 16
`5.1
`PLMN selection ....................................................................................................................................................... 16
`5.1.1
`Void .................................................................................................................................................................... 16
`5.1.2
`Support for PLMN selection............................................................................................................................. 16
`5.1.2.1
`General ......................................................................................................................................................... 16
`5.1.2.2
`E-UTRA and NB-IoT case.......................................................................................................................... 16
`5.1.2.3
`UTRA case................................................................................................................................................... 16
`5.1.2.4
`GSM case ..................................................................................................................................................... 17
`5.1.2.5
`CDMA2000 case ......................................................................................................................................... 17
`5.2
`Cell selection and reselection ................................................................................................................................. 17
`5.2.1
`Introduction........................................................................................................................................................ 17
`5.2.2
`States and state transitions in Idle Mode.......................................................................................................... 18
`5.2.3
`Cell Selection process ....................................................................................................................................... 19
`5.2.3.1
`Description ................................................................................................................................................... 19
`5.2.3.2
`Cell Selection Criterion............................................................................................................................... 20
`5.2.3.2a
`Cell Selection Criterion for NB-IoT........................................................................................................... 21
`5.2.3.3
`CSG cells and Hybrid cells in Cell Selection ............................................................................................ 21
`5.2.3.4
`GSM case in Cell Selection ........................................................................................................................ 21
`5.2.3.5
`UTRAN case in Cell Selection ................................................................................................................... 21
`5.2.4
` Cell Reselection evaluation process ................................................................................................................ 22
`5.2.4.1
`Reselection priorities handling ................................................................................................................... 22
`5.2.4.2
`Measurement rules for cell re-selection ..................................................................................................... 23
`5.2.4.2a
`Measurement rules for cell re-selection for NB-IoT ................................................................................. 24
`5.2.4.3
`Mobility states of a UE ............................................................................................................................... 24
`5.2.4.3.1
`Scaling rules ........................................................................................................................................... 25
`5.2.4.4
`Cells with cell reservations, access restrictions or unsuitable for normal camping ................................ 25
`5.2.4.5
`E-UTRAN Inter-frequency and inter-RAT Cell Reselection criteria ...................................................... 26
`5.2.4.6
`Intra-frequency and equal priority inter-frequency Cell Reselection criteria.......................................... 27
`5.2.4.6a
`Reselection for enhanced coverage ............................................................................................................ 28
`5.2.4.7
`Cell reselection parameters in system information broadcasts................................................................. 28
`5.2.4.7.1
`Speed dependant reselection parameters .............................................................................................. 30
`5.2.4.8
`Cell reselection with CSG cells .................................................................................................................. 31
`5.2.4.8.1
`Cell reselection from a non-CSG cell to a CSG cell ........................................................................... 31
`5.2.4.8.2
`Cell reselection from a CSG cell .......................................................................................................... 31
`5.2.4.9
`Cell reselection with Hybrid cells .............................................................................................................. 32
`5.2.4.10
`E-UTRAN Inter-frequency Redistribution procedure............................................................................... 32
`5.2.4.10.1
`Redistribution target selection .............................................................................................................. 32
`5.2.4.11
`Cell reselection when storing UE AS context ........................................................................................... 33
`5.2.5
`Void .................................................................................................................................................................... 33
`5.2.6
`Camped Normally state..................................................................................................................................... 33
`5.2.7
`Cell Selection when leaving RRC_CONNECTED state ................................................................................ 33
`5.2.7a
`Cell Selection when leaving RRC_CONNECTED state for NB-IoT ............................................................ 34
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`Any Cell Selection state .................................................................................................................................... 34
`5.2.8
`Any Cell Selection state for NB-IoT................................................................................................................ 34
`5.2.8a
`Camped on Any Cell state ................................................................................................................................ 34
`5.2.9
`Cell Reservations and Access Restrictions ............................................................................................................ 35
`5.3
`Cell status and cell reservations........................................................................................................................ 35
`5.3.1
`Access control.................................................................................................................................................... 36
`5.3.2
`Emergency call .................................................................................................................................................. 36
`5.3.3
`Tracking Area registration ...................................................................................................................................... 36
`5.4
`Support for manual CSG selection ......................................................................................................................... 36
`5.5
`E-UTRA case ..................................................................................................................................................... 36
`5.5.1
`UTRA case......................................................................................................................................................... 36
`5.5.2
`RAN-assisted WLAN interworking ....................................................................................................................... 37
`5.6
`RAN assistance parameter handling in RRC_IDLE ....................................................................................... 37
`5.6.1
`Access network selection and traffic steering rules ........................................................................................ 37
`5.6.2
` RAN assistance parameters definition ............................................................................................................ 38
`5.6.3
`Reception of broadcast information ........................................................................................ 39
`6
`Reception of system information............................................................................................................................ 39
`6.1
`Reception of MBMS ............................................................................................................................................... 39
`6.2
`Paging................................................................................................................................ 39
`7
`Discontinuous Reception for paging ...................................................................................................................... 39
`7.1
`Subframe Patterns.................................................................................................................................................... 41
`7.2
`Paging in extended DRX......................................................................................................................................... 41
`7.3
`Logged measurements .......................................................................................................... 42
`8
`Accessibility measurements................................................................................................... 43
`9
`10 Mobility History Information................................................................................................. 43
`11
`Sidelink operation ................................................................................................................ 43
`11.1
`Sidelink communication and V2X sidelink communication ................................................................................ 43
`11.2
`Sidelink discovery ................................................................................................................................................... 43
`11.3
`Sidelink synchronisation ......................................................................................................................................... 43
`11.4
`Cell selection and reselection for sidelink ............................................................................................................. 43
`11.4.1
`Parameters used for cell selection and reselection triggered for sidelink ...................................................... 44
`Annex A (informative):
`Void ................................................................................................. 45
`Annex C (informative):
`Change history ................................................................................. 47
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`Foreword
`This Technical Specification has been produced by the 3rd Generation Partnership Project (3GPP).
`The contents of the present document are subject to continuing work within the TSG and may change following formal
`TSG approval. Should the TSG modify the contents of the present document, it will be re-released by the TSG with an
`identifying change of release date and an increase in version number as follows:
`Version x.y.z
`where:
`x
`the first digit:
`1 presented to TSG for information;
`2 presented to TSG for approval;
`3 or greater indicates TSG approved document under change control.
`the second digit is incremented for all changes of substance, i.e. technical enhancements, corrections,
`updates, etc.
`the third digit is incremented when editorial only changes have been incorporated in the document.
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`y
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`Scope
`1
`The present document specifies the Access Stratum (AS) part of the Idle Mode procedures applicable to a UE. The non-
`access stratum (NAS) part of Idle mode procedures and processes is specified in [5].
`The present document specifies the model for the functional division between the NAS and AS in a UE.
`The present document applies to all UEs that support at least E-UTRA, including multi-RAT UEs as described in 3GPP
`specifications, in the following cases:
`- When the UE is camped on an E-UTRA cell;
`- When the UE is searching for a cell to camp on;
`NOTE: When the UE is camped on or searching for a cell to camp on belonging to other RATs, the UE behaviour
`is described in the specifications of the other RAT.
`
`References
`2
`The following documents contain provisions which, through reference in this text, constitute provisions of the present
`document.
`- References are either specific (identified by date of publication, edition number, version number, etc.) or non-
`specific.
`- For a specific reference, subsequent revisions do not apply.
`- For a non-specific reference, the latest version applies. In the case of a reference to a 3GPP document (including
`a GSM document), a non-specific reference implicitly refers to the latest version of that document in the same
`Release as the present document.
` [1]
`3GPP TR 25.990: "Vocabulary for UTRAN".
`[2]
`3GPP TS 36.300: "E-UTRA and E-UTRAN Overall Description; Stage 2".
`[3]
`3GPP TS 36.331: "E-UTRA; Radio Resource Control (RRC) - Protocol Specification".
`[4]
`3GPP TS 22.011: "Service accessibility".
`[5]
`3GPP TS 23.122: "NAS functions related to Mobile Station (MS) in idle mode".
`[6]
`3GPP TS 36.213: "E-UTRA; Physical layer procedures".
`[7]
`3GPP TS 36.214: "E-UTRA; Physical layer; Measurements".
`[8]
`3GPP TS 25.304: "User Equipment (UE) procedures in idle mode and procedures for cell
`reselection in connected mode"
`3GPP TS 43.022: "Functions related to Mobile Station in idle mode and group receive mode".
`3GPP TS 36.133: "Requirements for Support of Radio Resource Management".
`void
`void
`void
`void
`void
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`[9]
`[10]
`[11]
`[12]
`[13]
`[14]
`[15]
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`[16]
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`[17]
`[18]
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`[19]
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`[20]
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`[21]
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`[22]
`[23]
`[24]
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`[25]
`[26]
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`[27]
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`[28]
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`[29]
`[30]
`[31]
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`[32]
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`[33]
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`[34]
`[35]
`[36]
`
`3GPP TS 24.301: "Non-Access-Stratum (NAS) protocol for Evolved Packet System (EPS); Stage
`3"
`3GPP2 C.S0024-C v2.0: "cdma2000 High Rate Packet Data Air Interface Specification".
`3GPP2 C.S0005-F v1.0: "Upper Layer (Layer 3) Signalling Standard for cdma2000 Spread
`Spectrum Systems".
`3GPP TS 25.304: "User Equipment (UE) procedures in idle mode and procedures for cell
`reselection in connected mode".
`3GPP TS 24.008: "Mobile Radio Interface Layer 3 specification; Core Network Protocols;
`Stage 3"
`3GPP TS 37.320: "Universal Terrestrial Radio Access (UTRA) and Evolved Universal Terrestrial
`Radio Access (E-UTRA); Radio measurement collection for Minimization of Drive Tests (MDT);
`Overall description; Stage 2".
`3GPP TS 26.346: "Multimedia Broadcast/Multicast Service (MBMS); Protocols and codecs".
`3GPP TS 23.401: "Evolved Universal Terrestrial Radio Access Network (E-UTRAN) access".
`3GPP TS 23.682: "Architecture enhancements to facilitate communications with packet data
`networks and applications".
`3GPP TS 23.402: "Architecture enhancements for non-3GPP accesses".
`IEEE 802.11, Part 11: "Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY)
`specifications, IEEE Std.".
`Wi-Fi Alliance Technical Committee, Hotspot 2.0 Technical Task Group: "Hotspot 2.0 (Release 2)
`Technical Specification".
`3GPP TS 24.302: "Access to the 3GPP Evolved Packet Core (EPC) via non-3GPP access
`networks".
`3GPP TS 23.303: "Proximity-based services (ProSe); Stage 2".
`3GPP TS 36.321: "E-UTRA; Medium Access Control (MAC) protocol specification".
`3GPP TS 24.105: "Application specific Congestion control for Data Communication (ACDC)
`Management Object (MO)".
`3GPP TS 31.102: "Characteristics of the Universal Subscriber Identity Module (USIM)
`application".
`3GPP TS 36.101: "Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE)
`radio transmission and reception".
`Void
`3GPP TS 23.003: "Numbering, addressing and identification".
`3GPP TS 23.285: "Technical Specification Group Services and System Aspects; Architecture
`enhancements for V2X services".
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`3
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`Definitions and abbreviations
`
`Definitions
`3.1
`For the purposes of the present document, the following terms and definitions apply:
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`Acceptable Cell: A cell that satisfies certain conditions as specified in 4.3. A UE can always attempt emergency calls
`on an acceptable cell, but restriction as in 5.3.3 apply.
`CSG Whitelist: A list provided by NAS containing all the CSG identities and their associated PLMN IDs of the CSGs
`to which the subscriber belongs.
`NOTE: This list is known as Allowed CSG List in Rel-8 Access Stratum specifications.
`Available PLMN(s): One or more PLMN(s) for which the UE has found at least one cell and read its PLMN
`identity(ies).
`Barred Cell: A cell a UE is not allowed to camp on.
`Camped on a cell: UE has completed the cell selection/reselection process and has chosen a cell. The UE monitors
`system information and (in most cases) paging information.
`Camped on any cell: UE is in idle mode and has completed the cell selection/reselection process and has chosen a cell
`irrespective of PLMN identity.
`Closed Subscriber Group (CSG): A Closed Subscriber Group identifies subscribers of an operator who are permitted
`to access one or more cells of the PLMN but which have restricted access (CSG cells).
`Commercial Mobile Alert System: Public Warning System that delivers Warning Notifications provided by Warning
`Notification Providers to CMAS capable UEs.
`CSG cell: A cell broadcasting a CSG indication that is set to TRUE and a specific CSG identity.
`CSG identity: An identifier broadcast by a CSG or hybrid cell/cells and used by the UE to facilitate access for
`authorised members of the associated Closed Subscriber Group.
`CSG member cell: a cell broadcasting the identity of the selected PLMN, registered PLMN or equivalent PLMN and
`for which the CSG whitelist of the UE includes an entry comprising cell’s CSG ID and the respective PLMN identity.
`DRX cycle: Individual time interval between monitoring Paging Occasion for a specific UE.
`eDRX cycle: Time interval between the first Paging Occasions occurring after successive extended DRX periods.
`eCall Only Mode: A UE configuration option that allows the UE to attach at EPS and register in IMS to perform only
`eCall Over IMS, and a non-emergency IMS call for test and/or terminal reconfiguration services.
`EHPLMN: Any of the PLMN entries contained in the Equivalent HPLMN list [5].
`Equivalent PLMN list: List of PLMNs considered as equivalent by the UE for cell selection, cell reselection, and
`handover according to the information provided by the NAS.
`EU-Alert: Public Warning System that delivers Warning Notifications provided by Warning Notification Providers
`using the same AS mechanisms as defined for CMAS.
`Home PLMN: A PLMN where the Mobile Country Code (MCC) and Mobile Network Code (MNC) of the PLMN
`identity are the same as the MCC and MNC of the IMSI.
`HNB Name: The Home eNodeB Name is a broadcast string in free text format that provides a human readable name for
`the Home eNodeB CSG identity and any broadcasted PLMN identity.
`Hybrid cell: A cell broadcasting a CSG Indicator that is set to FALSE and a specific CSG identity.
`Hyper SFN: Index broadcast in System Information that increments at every SFN wrap around (i.e every 10.24s).
`Korean Public Alert System (KPAS): Public Warning System that delivers Warning Notifications provided by
`Warning Notification Providers using the same AS mechanisms as defined for CMAS.
`Location Registration (LR): UE registers its presence in a registration area, for instance regularly or when entering a
`new tracking area.
`MBMS-dedicated cell: cell dedicated to MBMS transmission.
`MBMS/Unicast-mixed cell: cell supporting both unicast and MBMS transmissions.
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`FeMBMS/Unicast-mixed cell: cell supporting MBMS transmission and unicast transmission as SCell.
`NB-IoT: NB-IoT allows access to network services via E-UTRA with a channel bandwidth limited to 200 kHz.
`Paging Time Window: The period configured for a UE in extended DRX, during which the UE monitors Paging
`Occasions following DRX cycle.
`Power saving mode: Mode allowing the UE to reduce its power consumption, as defined in TS 24.301 [16], TS 23.401
`[23], TS 23.682 [24].
`Process: A local action in the UE invoked by a RRC procedure or an Idle Mode procedure.
`Radio Access Technology: Type of technology used for radio access, for instance E-UTRA, UTRA, GSM,
`CDMA2000 1xEV-DO (HRPD) or CDMA2000 1x (1xRTT).
`Registered PLMN: This is the PLMN on which certain Location Registration outcomes have occurred [5].
`Registration Area: (NAS) registration area is an area in which the UE may roam without a need to perform location
`registration, which is a NAS procedure.
`Reserved Cell: A cell on which camping is not allowed, except for particular UEs, if so indicated in the system
`information.
`Restricted Cell: A cell on which camping is allowed, but access attempts are disallowed for UEs whose access classes
`are indicated as barred.
`Selected PLMN: This is the PLMN that has been selected by the NAS, either manually or automatically.
`Serving cell: The cell on which the UE is camped.
`Sidelink: UE to UE interface for sidelink communication, V2X sidelink communication and sidelink discovery. The
`Sidelink corresponds to the PC5 interface as defined in TS 23.303 [29].
`Sidelink communication: AS functionality enabling ProSe Direct Communication as defined in TS 23.303 [29],
`between two or more nearby UEs, using E-UTRA technology but not traversing any network node. The terminology
`"sidelink communication" without "V2X" prefix only concerns PS unless specifically stated otherwise.
`Sidelink discovery: AS functionality enabling ProSe Direct Discovery as defined in TS 23.303 [29], using E-UTRA
`technology but not traversing any network node.
`Strongest cell: The cell on a particular carrier that is considered strongest according to the layer 1 cell search procedure
`[6], [7].
`Suitable Cell: This is a cell on which an UE may camp. For a E-UTRA cell, the criteria are defined in subclause 4.3,
`for a UTRA cell in [8], and for a GSM cell the criteria are defined in [9].
`V2X sidelink communication: AS functionality enabling V2X Communication as defined in TS 23.285 [36], between
`nearby UEs, using E-UTRA technology but not traversing any network node.
`
`Symbols
`3.2
`For the purposes of the present document, the following symbols apply:
`<symbol>
`<Explanation>
`3.3
`Abbreviations
`For the purposes of the present document, the following abbreviations apply:
`1xRTT
`CDMA2000 1x Radio Transmission Technology
`AS
`Access Stratum
`AC
`Access Class (of the USIM)
`ACDC
`Application specific Congestion control for Data Communication
`BCCH
`Broadcast Control Channel
`BR-BCCH
`Bandwidth Reduced Broadcast Control Channel
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`BSS
`CMAS
`CSG
`DRX
`DL-SCH
`EHPLMN
`EPC
`EPS
`ETWS
`E-UTRA
`E-UTRAN
`FDD
`GERAN
`HPLMN
`H-SFN
`HRPD
`IMSI
`MBMS
`MBSFN
`MCC
`MCCH
`MDT
`MM
`MNC
`MPDCCH
`MTCH
`NAS
`NB-IoT
`PLMN
`ProSe
`PSM
`PTW
`PWS
`RAT
`RRC
`SAP
`SIBX
`TDD
`UE
`UMTS
`USIM
`UTRA
`UTRAN
`V2X
`
`Basic Service Set
`Commercial Mobile Altert System
`Closed Subscriber Group
`Discontinuous Reception
`Downlink Shared Channel
`Equivalent Home PLMN
`Evolved Packet Core
`Evolved Packet System
`Earthquake and Tsunami Warning System
`Evolved UMTS Terrestrial Radio Access
`Evolved UMTS Terrestrial Radio Access Network
`Frequency Division Duplex
`GSM/EDGE Radio Access Network
`Home PLMN
`Hyper System Frame Number
`High Rate Packet Data
`International Mobile Subscriber Identity
`Multimedia Broadcast-Multicast Service
`Multimedia Broadcast multicast service Single Frequency Network
`Mobile Country Code
`Multicast Control Channel
`Minimization of Drive Tests
`Mobility Management
`Mobile Network Code
`MTC Physical Downlink Control Channel
`Multicast Traffic Channel
`Non-Access Stratum
`NarrowBand Internet of Things
`Public Land Mobile Network
`Proximity-based Services
`Power Saving Mode
`Paging Time Window
`Public Warning System
`Radio Access Technology
`Radio Resource Control
`Service Access Point
`SystemInformationBlockTypeX
`Time Division Duplex
`User Equipment
`Universal Mobile Telecommunications System
`Universal Subscriber Identity Module
`UMTS Terrestrial Radio Access
`UMTS Terrestrial Radio Access Network
`Vehicle-to-Everything
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`4
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`General description of Idle mode
`
`Overview
`4.1
`The idle mode tasks can be subdivided into four processes:
`- PLMN selection;
`- Cell selection and reselection;
`- Location registration;
`- Support for manual CSG selection.
`The relationship between these processes is illustrated in Figure 4.1-1.
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`Manual Mode
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`Indication
`to user
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`PLMN Selection
`
`
`Location
`Registration
`response
`
`PLMNs
`available
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`Automatic mode
`
`Available (PLMN,
`CSG ID)s to NAS
`
`NAS Control
`
`Radio measurements
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`Support for manual
`CSG selection
`
`CSG
`selected
`
`Cell Selection
`and Reselection
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`MBMS Frequency
`Prioritization
`
`
`
`PLMN selected
`(optional CSG
`ID)
`
`
`Registration
`Area
`changes
`
`Location
`Registration
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`Service requests
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`Figure 4.1-1: Overall Idle Mode process
`
`When a UE is switched on, a public land mobile network (PLMN) is selected by NAS. For the selected PLMN,
`associated RAT(s) may be set [5]. The NAS shall provide a list of equivalent PLMNs, if available, that the AS shall use
`for cell selection and cell reselection.
`With the cell selection, the UE searches for a suitable cell of the selected PLMN and chooses that cell to provide
`available services, further the UE shall tune to its control channel. This choosing is known as "camping on the cell".
`The UE shall, if necessary, then register its presence, by means of a NAS registration procedure, in the tracking area of
`the chosen cell and as outcome of a successful Location Registration the selected PLMN becomes the registered PLMN
`[5].
`If the UE finds a more suitable cell, according to the cell reselection criteria, it reselects onto that cell and camps on it.
`If the new cell does not belong to at least one tracking area to which the UE is registered, location registration is
`performed.
`If necessary, the UE shall search for higher priority PLMNs at regular time intervals as described in [4] and search for a
`suitable cell if another PLMN has been selected by NAS.
`Search of available CSGs may be triggered by NAS to support manual CSG selection.
`If the UE loses coverage of the registered PLMN, either a new PLMN is selected automatically (automatic mode), or an
`indication of which PLMNs are available is given to the user, so that a manual selection can be made (manual mode).
`Registration is not performed by UEs only capable of services that need no registration.
`The UE may perform sidelink communication or V2X sidelink communication or sidelink discovery while in-coverage
`or out-of-coverage for sidelink, as specified in section 11.
`The purpose of camping on a cell in idle mode is fivefold:
`a) It enables the UE to receive system information from the PLMN.
`b) When registered and if the UE wishes to establish an RRC connection, it can do this by initially accessing the
`network on the control channel of the cell on which it is camped.
`
`3GPP
`
`

`

`
`Release 14
`
`12
`
`3GPP TS 36.304 V14.5.0 (2017-12)
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`c) If the PLMN receives a call for the registered UE, it knows (in most cases) the set of tracking areas in which the
`UE is camped. It can then