2. UE能力可分为无线接入相关能力及核心网相关能力。The UE Capability information is made up of the UE Radio Capabilityinformation and the UE Core Network Capability information。 涉及到UE能力的规范比较多，这里先列出规范号，分别是36.101/36.306/23.401/36.331/24.008。
参考上图，如果消息9中，携带了UE Radio Capability 的IE，则eNB不会发送UECapabilityEnquiry消息给UE，即没有10/11/12的过程； 否则，如果消息9中没有携带UE能力，则基站会发起UE能力查询过程，这在第一次入网（ATTACH/TAU）的过程中经常会看到。而UE上报了无线能力信息到eNB之后，eNB再给MME发送Capability Info Indication消息，传递并上报UE的能力信息至MME。
而在协议设计中，为了减少空口信令开销，MME会保存UE Radio Capability信息，而在S1流程INITIAL CONTEXT SETUP REQUEST消息中，MME还会把UE能力传递给eNB，故此时eNB无需针对UE发起UECapabilityEnquiry过程，因为UE能力可知。
但是，在UE在实行attach或者“first TAU following GERAN/UTRANAttach” 或“UE radio capability update”时， MME不会在INITIAL CONTEXT SETUP REQUEST消息中带UE Radio Capability信息给eNB的， 并会把本地保存的UE Radio Capability信息删除，故这三种情况，eNB会问UE要UE能力，在eNB获知之后还需上报给MME。
注："UEradio capability update" TAU is only supported for changes of GERAN and UTRAN radio capabilities in ECM-IDLE。
这里面有2个推论： 1. 在RRC-CONNECTED下，eNB也会一直保存UE Radio Capability信息。反过来，UE从RRC连接态转移到RRC空闲态下，UE的RRC连接的上下文会释放，自然eNB针对某个UE的能力信息也将删除。但此时MME不会删除UE的能力信息的，因为MME依然是MM-REGISTERED，除非UE去附着（detach）或其他。 2. UE无线能力信息如果发生改变，UE需要先发起detach，再attach。 一个很简单的例子，比如大家把CMCC的5模手机现在锁死在LTE单模下工作，相当于人为的改变了UE的能力，此时大家会发现UE的信号图标，会暗了，再亮了。 如果去跟信令的话，这就会是一次“UE能力改变”导致的“去附着+附着“ 的过程。这样去附着+附着机制，保证了UE能力信息的同步。
比如，如果ca-BandwidthClassDL-r10 为a类别，就说明UE下行只支撑1个载波； 如果ca-BandwidthClassDL-r10 为c类别，就说明UE下行支撑2个CC的载波聚合。 Class A: aggregated transmitted BW configuration <= 100PRBs and 1 component carrier。 Class C: aggregated transmitted BWconfiguration of 101 to 200 PRBs and 2 component carriers。
关于CA的类别，见后面的截图。
附录1：23401中关于UE能力处理过程的描述
5.11 UE Capability Handling
5.11.1 General
The UE Capability information is made up of the UE Radio Capabilityinformation and the UE Core Network Capability information.
5.11.2 UE Radio Capability Handling
The UE Radio Capability information contains information on RATsthat the UE supports (e.g. power class, frequency bands, etc). Consequently,this information can be sufficiently large (e.g. >50 octets) that it isundesirable to send it across the radio interface at every transition from ECM‑IDLEto ECM‑CONNECTED. To avoidthis radio overhead, the MME stores the UE Capability information during ECM‑IDLEstate and the MME shall, if it is available, send its most up to date UE RadioCapability information to the E‑UTRAN in the S1 interface INITIAL CONTEXT SETUPREQUEST message unless the UE is performing an Attach procedure or a TrackingArea Update procedure for the "first TAU following GERAN/UTRANAttach" orfor a "UE radio capabilityupdate".
NOTE 1: Fora GERAN/UTRAN/E-UTRAN capable UE, this UE Radio Capability information isbroadly equivalent to the combination of the MS Radio Access capability sent in theTS 24.008 [47] Attach Request message plus the Inter RAT Handoverinformation sent in the TS 24.008 [47] Attach Complete message.
If the UE is performing an Attach procedureor a Tracking Area Update procedure for the "first TAU followingGERAN/UTRAN Attach" or for "UE radio capability update", the MMEshall delete (or mark as deleted) any UE Radio Capability information that ithas stored, and, if the MME sends an S1 interface INITIAL CONTEXT SETUP REQUESTmessage during that procedure, the MME shall not send any UE Radio Capabilityinformation to the E‑UTRAN in that message. This triggers the E‑UTRAN torequest the UE Radio Capability from the UE and upload it to the MME in the S1interface UE CAPABILITY INFO INDICATION message.
If the UE is performing a Service Request(or other) procedure and the MME does not have UE Radio Capability informationavailable (or it is available, but marked as "deleted"), then the MMEsends an S1 interface INITIAL CONTEXT SETUP REQUEST message to the E‑UTRANwithout any UE Radio Capability information in it. This triggers the E‑UTRAN torequest the UE Radio Capability from the UE and upload it to the MME in the S1interface UE CAPABILITY INFO INDICATION message.
NOTE 2: Thisuse of the INITIAL CONTEXT SETUP REQUEST message means that for a signallingonly procedure such as a periodic Tracking Area Update, the UE Radio Capability would not be sent to the E‑UTRAN.
NOTE 3: If a "first TAU following GERAN/UTRAN Attach" Tracking Area Update isperformed during ECM-CONNECTED mode, e.g. after an inter RAT handover, noINITIAL CONTEXT SETUP REQUEST is sent and the UE Radio Capability informationin the MME will remain deleted until the next ECM-IDLE to ECM-CONNECTEDtransition (or later, e.g. if the next activity from the UE is another TrackingArea Update).
The UE Radio Capability is not provided directly from one CN node toanother. It will be uploaded to the MME when the E-UTRAN requests the UE RadioCapability information from the UE.
During handover via the MME (both intra RAT and inter RAT), the UERadio Capability is transferred in the "source to target transparent container".Even in the case of handover from a different RAT, this UE Radio Capabilityshould be the full radio capability information for all of the 3GPP RATs thatthat UE supports.
NOTE 4: For example in the case of a GERAN/UTRAN/E-UTRAN capable UE being handed over fromGERAN to E-UTRAN, the "source to target transparent container" wouldcarry UTRAN, GERAN and E-UTRAN radio access capabilities. This is necessary toenable subsequent handovers to a different (and/or the original) RAT.
To allow for the addition of future radio technologies, frequencybands, and other enhancements, the MME shall store the UE Radio CapabilityInformation even if it is larger than specified in TS 36.331 [37], upto a maximum size of 510 octets.
NOTE 5: The510 octet value comes from the information element encoding rulesdescribed in TS 24.007 [45] and the assumption that the informationcontained within this UE Radio Capability Information Element stored by the MMEis the equivalent of information signalled in two information elements in theGERAN NAS signalling for the case of GERAN to E‑UTRAN PS handover.
The E‑UTRAN stores the UE Radio Capability information, received inthe S1 interface INITIAL CONTEXT SETUP REQUEST message or obtained from the UE,for the duration of the RRC connection for that UE.
If the UE's UE Radio Capability information changes while inECM-IDLE state (including cases of being in GERAN/UTRAN coverage), the UE shallperform a Tracking Area Update indicating "UE radio capabilityupdate" when it next returns to E‑UTRAN coverage.
NOTE 6: Inthis release of the specifications, "UE radio capability update" isonly supported for changes of GERAN and UTRAN radio capabilities in ECM-IDLE.Any change in the UE's E‑UTRAN capabilities requires the UE to detach and thenre-attach to the system.
5.11.3 UE Core Network Capability
The UE Core Network Capability is splitinto the UE Network Capability IE (mostly for E-UTRAN access related corenetwork parameters) and the MS Network Capability IE (mostly for UTRAN/GERAN accessrelated core network parameters) and contains non radio-related capabilities,e.g. the NAS security algorithms etc. Both the UE Network Capability and the MSNetwork Capability are transferred between CN nodes at MME to MME, MME to SGSN,SGSN to SGSN, and SGSN to MME changes. (……)
附录2：36331中关于UE能力中的FGI的定义
B.1 Feature group indicators
This annex contains the definitions of thebits in field featureGroupIndicators.
In this release of the protocol, the UE shall include the field feature Group Indicators in the IE UE-EUTRA-Capability. All the functionalities defined within the field feature Group Indicators defined in Table B.1-1 are mandatory for the UE, if the related capability (frequency band, RAT or SR-VCC) is also supported. For a specific indicator, if all functionalities for a feature group listed in Table B.1-1 have been implemented and tested, the UE shall set theindicator as one (1), else (i.e. if any one of the functionalities in a featuregroup listed in Table B.1-1, which have not been implemented or tested), the UE shall set the indicator as zero (0).
The UE shall set all indicators that correspond to RATs not supported by the UE as zero (0).
The UE shall set all indicators, which do not have a definition in Table B.1-1, as zero (0).
If the optional field featureGroupIndicators is not included by a UE of a future release,the network may assume that all features pertaining to the RATs supported bythe UE, listed in Table B.1-1 and deployed in the network, have beenimplemented and tested by the UE.
In Table B.1-1, a 'VoLTE capable UE'corresponds to a UE that is capable of the "Voice domain preference for E-UTRAN" defined in TS 24.301 [35] being set to "IMS PS voiceonly", "IMS PS voice preferred, CS voice as secondary" or "CS voice preferred, IMS PS voice as secondary".
Table B.1-1: Definitions of feature groupindicators
Index of indicator (bit number)
Definition(description of the supported functionality, if indicator set to one)
Notes
If indicated "Yes" the feature shall be implemented and successfully tested for this version of the specification
1 (leftmost bit)
- Intra-subframe frequency hopping for PUSCH scheduled by UL grant- DCI format 3a (TPC commands for PUCCH and PUSCH with single bit power adjustments)- PDSCH transmission mode 5- Aperiodic CQI/PMI/RI reporting on PUSCH: Mode 2-0 – UE selected subband CQI without PMI- Aperiodic CQI/PMI/RI reporting on PUSCH: Mode 2-2 – UE selected subband CQI with multiple PMI
2
- Simultaneous CQI and ACK/NACK on PUCCH, i.e. PUCCH format 2a and 2b- Absolute TPC command for PUSCH- Resource allocation type 1 for PDSCH- Periodic CQI/PMI/RI reporting on PUCCH: Mode 2-0 – UE selected subband CQI without PMI- Periodic CQI/PMI/RI reporting on PUCCH: Mode 2-1 – UE selected subband CQI with single PMI
3
- 5bit RLC UM SN- 7bit PDCP SN
- can only be set to 1 if the UE has set bit number 7 to 1.
Yes, if UE supports VoLTE
4
- Short DRX cycle
- can only be set to 1 if the UE has set bit number 5 to 1.
5
- Long DRX cycle- DRX command MAC control element
Yes
6
- Prioritised bit rate
Yes
7
- RLC UM
- can only be set to 0 if the UE does not support VoLTE
Yes, if UE supports VoLTE
8
- EUTRA RRC_CONNECTED to UTRA CELL_DCH PS handover
- can only be set to 1 if the UE has set bit number 22 to 1
Yes, if UE supports UTRA
9
- EUTRA RRC_CONNECTED to GERAN GSM_Dedicated handover
- related to SR-VCC- can only be set to 1 if the UE has set bit number 23 to 1
10
- EUTRA RRC_CONNECTED to GERAN (Packet_) Idle by Cell Change Order- EUTRA RRC_CONNECTED to GERAN (Packet_) Idle by Cell Change Order with NACC (Network Assisted Cell Change)
11
- EUTRA RRC_CONNECTED to CDMA2000 1xRTT CS Active handover
- related to SR-VCC- can only be set to 1 if the UE has sets bit number 24 to 1
12
- EUTRA RRC_CONNECTED to CDMA2000 HRPD Active handover
- can only be set to 1 if the UE has set bit number 26 to 1
13
- Inter-frequency handover
- can only be set to 1 if the UE has set bit number 25 to 1
- can only be set to 1 if the UE has set at least one of the bit number 22, 23, 24 or 26 to 1.
16
- non-ANR related intra-frequency periodical measurement reporting;- non-ANR related inter-frequency periodical measurement reporting, if the UE has set bit number 25 to 1; and- non-ANR related inter-RAT periodical measurement reporting for UTRAN, GERAN, 1xRTT or HRPD, if the UE has set bit number 22, 23, 24 or 26 to 1, respectively. NOTE: “non-ANR related periodical measurement reporting” corresponds only to ‘periodical’ trigger type with purpose set to ‘reportStrongestCells’. Event triggered periodical reporting (i.e., ‘event’ trigger type with reportAmount > 1) is a mandatory functionality of event triggered reporting and therefore not the subject of this bit.
Yes
17
- Periodical measurement reporting for SON / ANR- ANR related intra-frequency measurement reporting events
- can only be set to 1 if the UE has set bit number 5 to 1.
Yes
18
- ANR related inter-frequency measurement reporting events
- can only be set to 1 if the UE has set bit number 5 to 1.
Yes, unless UE only supports band 13
19
- ANR related inter-RAT measurement reporting events
- can only be set to 1 if the UE has set bit number 5 to 1.
20
If bit number 7 is set to ‘0’:- SRB1 and SRB2 for DCCH + 8x AM DRB If bit number 7 is set to ‘1’:- SRB1 and SRB2 for DCCH + 8x AM DRB- SRB1 and SRB2 for DCCH + 5x AM DRB + 3x UM DRB NOTE: UE which indicate support for a DRB combination also support all subsets of the DRB combination. Therefore, release of DRB(s) never results in an unsupported DRB combination.
- Regardless of what bit number 7 and bit number 20 is set to, UE shall support at least SRB1 and SRB2 for DCCH + 4x AM DRB- Regardless of what bit number 20 is set to, if bit number 7 is set to ‘1’, UE shall support at least SRB1 and SRB2 for DCCH + 4x AM DRB + 1x UM DRB
Yes
21
- Predefined intra- and inter-subframe frequency hopping for PUSCH with N_sb > 1- Predefined inter-subframe frequency hopping for PUSCH with N_sb > 1
22
- UTRAN measurements, reporting and measurement reporting event B2 in E-UTRA connected mode
Yes, if UE supports UTRA
23
- GERAN measurements, reporting and measurement reporting event B2 in E-UTRA connected mode
24
- 1xRTT measurements, reporting and measurement reporting event B2 in E-UTRA connected mode
Yes, if UE supports enhanced 1xRTT CSFB
25
- Inter-frequency measurements and reporting in E-UTRA connected mode
Yes, unless UE only supports band 13
26
- HRPD measurements, reporting and measurement reporting event B2 in E-UTRA connected mode
Yes, if UE supports HRPD
27
- EUTRA RRC_CONNECTED to UTRA CELL_DCH CS handover
- related to SR-VCC- can only be set to 1 if the UE has set bit number 8 to 1
28
- TTI bundling
29
- Semi-Persistent Scheduling
30
Undefined
31
Undefined
32
Undefined
Clarificationfor mobility from EUTRAN and inter-frequency handover within EUTRAN
There are several feature groups related to mobility from E-UTRAN and inter-frequency handover within EUTRAN. The description of these features is based on the assumption that we have 5 main "functions"related to mobility from E-UTRAN:
A. Supportof measurements and cell reselection procedure in idle mode
B. Supportof RRC release with redirection procedure in connected mode
C. Supportof Network Assisted Cell Change in connected mode
D. Supportof measurements and reporting in connected mode
E. Supportof handover procedure in connected mode
All functions can be applied for mobility to Inter-frequency to EUTRAN, GERAN, UTRAN, CDMA2000 HRPD and CDMA2000 1xRTT except for function C) which is only applicablefor mobility to GERAN. Table B.1-2 below summarises the mobility functions thatare supported based on the UE capability signaling (band support) and thesetting of the feature group support indicators.
Table B.1-2: Mobility from E-UTRAN
Feature
GERAN
UTRAN
HRPD
1xRTT
EUTRAN
A. Measurements and cell reselection procedure in E-UTRA idle mode
Supported if GERAN band support is indicated
Supported if UTRAN band support is indicated
Supported if CDMA2000 HRPD band support is indicated
Supported if CDMA2000 1xRTT band support is indicated
Supported for supported bands
B. RRC release with blind redirection procedure in E-UTRA connected mode
Supported if GERAN band support is indicated
Supported if UTRAN band support is indicated
Supported if CDMA2000 HRPD band support is indicated
Supported if CDMA2000 1xRTT band support is indicated
Supported for supported bands
C. Cell Change Order (with or without) Network Assisted Cell Change) in E-UTRA connected mode
Group 10
N.A.
N.A
N.A
N.A.
D. Inter-frequency/RAT measurements, reporting and measurement reporting event B2 (for inter-RAT) in E-UTRA connected mode
Group 23
Group 22
Group 26
Group 24
Group 25
E. Inter-frequency/RAT handover procedure in E-UTRA connected mode
Group 9 (GSM_connected handover)Separate UE capability bit defined in TS 36.306 for PS handover
Group 8 (PS handover) or Group 27 (SRVCC handover)
Group 12
Group 11
Group 13
In case measurements and reporting functionis not supported by UE, the network may still issue the mobility procedures redirection(B) and CCO (C) in a blind fashion.
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发表于 2016-4-6 09:18:30
