ETSI TR 125 912 V14.0.0 (2017-04)

ETSI TR 125 912 V14.0.0 (2017-04)






TECHNICAL REPORT
Universal Mobile Telecommunications System (UMTS);
LTE;
Feasibility study
for evolved Universal Terrestrial Radio Access (UTRA) and
Universal Terrestrial Radio Access Network (UTRAN)
(3GPP TR 25.912 version 14.0.0 Release 14)

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3GPP TR 25.912 version 14.0.0 Release 14 1 ETSI TR 125 912 V14.0.0 (2017-04)



Reference
RTR/TSGR-0025912ve00
Keywords
LTE,UMTS
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3GPP TR 25.912 version 14.0.0 Release 14 2 ETSI TR 125 912 V14.0.0 (2017-04)
Intellectual Property Rights
IPRs essential or potentially essential to the present document may have been declared to ETSI. The information
pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found
in ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in
respect of ETSI standards", which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web
server (https://ipr.etsi.org/).
Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee
can be given as to the existence of other IPRs not referenced in ETSI SR 000 314 (or the updates on the ETSI Web
server) which are, or may be, or may become, essential to the present document.
Foreword
This Technical Report (TR) has been produced by ETSI 3rd Generation Partnership Project (3GPP).
The present document may refer to technical specifications or reports using their 3GPP identities, UMTS identities or
GSM identities. These should be interpreted as being references to the corresponding ETSI deliverables.
The cross reference between GSM, UMTS, 3GPP and ETSI identities can be found under
http://webapp.etsi.org/key/queryform.asp.
Modal verbs terminology
In the present document "should", "should not", "may", "need not", "will", "will not", "can" and "cannot" are to be
interpreted as described in clause 3.2 of the ETSI Drafting Rules (Verbal forms for the expression of provisions).
"must" and "must not" are NOT allowed in ETSI deliverables except when used in direct citation.
ETSI

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3GPP TR 25.912 version 14.0.0 Release 14 3 ETSI TR 125 912 V14.0.0 (2017-04)
Contents
Intellectual Property Rights . 2
Foreword . 2
Modal verbs terminology . 2
Foreword . 7
1 Scope . 8
2 References . 8
3 Definitions, symbols and abbreviations . 8
3.1 Definitions . 8
3.2 Symbols . 8
3.3 Abbreviations . 9
4 Introduction . 10
5 Deployment scenario . 11
6 Radio interface protocol architecture for evolved UTRA . 11
6.1 User plane . 13
6.2 Control plane . 13
7 Physical layer for evolved UTRA . 14
7.1 Downlink transmission scheme . 14
7.1.1 Basic transmission scheme based on OFDMA . 14
7.1.1.1 Basic parameters . 14
7.1.1.1.1 Modulation scheme . 15
7.1.1.2 Multiplexing including reference-signal structure . 15
7.1.1.2.1 Downlink data multiplexing . 15
7.1.1.2.2 Downlink reference-signal structure . 15
7.1.1.2.3 Downlink L1/L2 Control Signaling . 15
7.1.1.3 MIMO and transmit diversity . 16
7.1.1.4 MBMS . 16
7.1.2 Physical layer procedure . 16
7.1.2.1 Scheduling . 16
7.1.2.2 Link adaptation . 17
7.1.2.3 HARQ . 17
7.1.2.4 Cell search . 17
7.1.2.5 Inter-cell interference mitigation . 18
7.1.3 Physical layer measurements . 18
7.1.3.1 UE measurements . 18
7.1.3.1.1 Measurements for Scheduling . 18
7.1.3.1.1.1 Channel Quality Measurements . 18
7.1.3.1.1.2 Measurements for Interference Coordination/Management . 19
7.1.3.1.2 Measurements for Mobility . 19
7.1.3.1.2.1 Intra-frequency neighbour measurements . 19
7.1.3.1.2.2 Inter-frequency neighbour measurements . 19
7.1.3.1.2.3 Inter RAT measurements . 19
7.1.3.1.2.4 Measurement gap control . 19
7.2 Uplink transmission scheme . 19
7.2.1 Basic transmission scheme . 19
7.2.1.1 Modulation scheme . 20
7.2.1.2 Multiplexing including reference signal structure . 20
7.2.1.2.1 Uplink data multiplexing . 20
7.2.1.2.2 Uplink reference-signal structure . 21
7.2.1.2.3 Multiplexing of L1/L2 control signaling . 21
7.2.1.2.4 Uplink L1/L2 Control Signalling. 21
7.2.1.3 MIMO . 22
7.2.1.4 Power De-rating Reduction . 22
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3GPP TR 25.912 version 14.0.0 Release 14 4 ETSI TR 125 912 V14.0.0 (2017-04)
7.2.2 Physical channel procedure. 22
7.2.2.1 Random access procedure . 22
7.2.2.1.1 Non-synchronized random access . 22
7.2.2.1.1.1 Power control for non-synchronized random access . 22
7.2.2.1.2 Synchronized random access . 22
7.2.2.2 Scheduling . 22
7.2.2.3 Link adaptation . 23
7.2.2.4 Power control . 23
7.2.2.5 HARQ . 23
7.2.2.6 Uplink timing control . 23
7.2.2.7 Inter-cell interference mitigation . 23
8 Layer 2 and RRC evolution for evolved UTRA . . 24
8.1 MAC sublayer . 25
8.1.1 Services and functions . 25
8.1.2 Logical channels . 25
8.1.2.1 Control channels . 26
8.1.2.2 Traffic channels . 26
8.1.3 Mapping between logical channels and transport channels . 26
8.1.3.1 Mapping in Uplink . 27
8.1.3.2 Mapping in downlink . 27
8.2 RLC sublayer . 27
8.3 PDCP sublayer . 28
8.4 RRC . 28
8.4.1 Services and functions . 28
8.4.2 RRC protocol states & state transitions . 29
9 Architecture for evolved UTRAN . 30
9.1 Evolved UTRAN architecture . 30
9.2 Functional split . 30
9.3 Interfaces . 31
9.3.1 S1 interface . 31
9.3.1.1 Definition . 31
9.3.1.2 S1-C RNL protocol functions . 31
9.3.1.3 S1-U RNL protocol functions . 31
9.3.1.4 S1-X2 similarities . 31
9.3.2 X2 interface . 31
9.3.2.1 Definition . 31
9.3.2.2 X2-C RNL Protocol Functions . 32
9.3.2.3 X2-U RNL Protocol Functions . 32
9.4 Intra-LTE-access-system mobility . 32
9.4.1 Intra-LTE-access-system mobility support for UE in LTE_IDLE . 32
9.4.2 Intra LTE-Access-System Mobility Support for UE in LTE_ACTIVE . 32
9.4.2.1 Description of Intra-LTE-Access Mobility Support for UEs in LTE_ACTIVE . 32
9.4.2.2 Solution for Intra-LTE-Access Mobility Support for UEs in LTE_ACTIVE . 32
9.4.2.2.1 C-plane handling: . 32
9.4.2.2.2 U-plane handling . 34
9.5 Inter 3GPP access system mobility . 34
9.5.1 Inter 3GPP access system mobility in Idle state . 34
9.5.2 Inter 3GPP access system mobility handover . 34
9.6 Resource establishment and QoS signalling . 34
9.6.1 QoS concept and bearer service architecture . 34
9.6.2 Resource establishment and QoS signalling . 34
9.7 Paging and C-plane establishment . 36
9.8 Evaluations on for E-UTRAN architecture and migration . 36
9.9 Support of roaming restrictions in LTE_ACTIVE . 36
10 RF related aspects of evolved UTRA . 37
10.1 Scalable bandwidth. 37
10.2 Spectrum deployment . 37
11 Radio resource management aspects of evolved UTRA . 38
11.1 Introduction . 38
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3GPP TR 25.912 version 14.0.0 Release 14 5 ETSI TR 125 912 V14.0.0 (2017-04)
11.2 Definition and description of RRM functions . 38
11.2.1 Radio Bearer Control (RBC) . 38
11.2.2 Radio Admission Control (RAC) . 38
11.2.3 Connection Mobility Control (CMC) . 38
11.2.4 Packet Scheduling (PSC) . 39
11.2.5 Inter-cell Interference Coordination (ICIC) . 39
11.2.6 Load Balancing (LB) . 39
11.2.7 Inter-RAT Radio Resource Management . 39
11.3 RRM architecture in LTE . 39
11.4 Support of load sharing and policy management across different Radio Access Technologies (RATs) . 40
12 System and terminal complexity . 40
12.1 Over all system complexity . 40
12.2 Physical layer complexity . 40
12.3 UE complexity . 41
13 Performance assessments . 42
13.1 Peak data rate . 42
13.2 C-plane latency . 43
13.2.1 FDD frame structure . 44
13.2.2 TDD frame structure type 1 . 45
13.2.3 TDD frame structure type 2 . 47
13.3 U-plane latency . 47
13.3.1 FDD frame structure . 48
13.3.2 TDD frame structure type 1 . 49
13.3.3 TDD frame structure type 2 . 50
13.4 User throughput . 51
13.4.1 Fulfilment of uplink user-throughput targets . 51
13.4.1.1 Initial performance evaluation . 51
13.4.1.2 UL user throughput performance evaluation . 51
13.4.2 Fulfilment of downlink user-throughput targets . 52
13.4.2.0 Initial performance evaluation . 52
13.4.2.1 Fulfilment of downlink user-throughput targets by enhancement techniques . 52
13.4.2.1.1 Performance Enhancement by Additional Transmit Antennas: 4 Transmit Antennas . 53
13.4.2.2 DL user throughput performance evaluation . 53
13.5 Spectrum efficiency . 54
13.5.1 Fulfilment of uplink spectrum-efficiency target . 54
13.5.1.1 Initial performance evaluation . 54
13.5.1.2 UL spectrum efficiency performance evaluation . 54
13.5.2 Fulfilment of downlink spectrum-efficiency target . 55
13.5.2.0 Initial performance evaluation . 55
13.5.2.1 Fulfilment of downlink spectrum-efficiency targets by enhancement techniques . 55
13.5.2.2 DL spectrum efficiency performance evaluation . 55
13.6 Mobility . 56
13.6.1 Features supporting various mobile velocities . 56
13.6.2 Assessment on U-plane interruption time during handover . 57
13.6.3 Means to minimise packet loss during handover . 59
13.7 Coverage. 59
13.8 Support for point to multipoint transmission . 60
13.8.1 Initial performance evaluation . 61
13.8.2 MBSFN performance evaluation . 61
13.9 Network synchronisation . 61
13.10 Co-existence and inter-working with 3GPP RAT . 62
13.11 General requirements . 62
13.11.1 Cost related requireme
...