ETSI TR 103 635 V1.1.1 (2019-11)

Digital Enhanced Cordless Telecommunications (DECT); DECT-2020 New Radio (NR) interface; Study on MAC and higher layers

DTR/DECT-00317

General Information

• Status: Published
• Publication Date: 14-Nov-2019
• Technical Committee: DECT - Digital Enhanced Cordless Telecommunications (DECT)
• Current Stage: 12 - Completion
• Due Date: 30-Dec-2019
• Completion Date: 15-Nov-2019

Standards Content (Sample)

ETSI TR 103 635 V1.1.1 (2019-11)






TECHNICAL REPORT
Digital Enhanced Cordless Telecommunications (DECT);
DECT-2020 New Radio (NR) interface;
Study on MAC and higher layers

---------------------- Page: 1 ----------------------
2 ETSI TR 103 635 V1.1.1 (2019-11)



Reference
DTR/DECT-00317
Keywords
5G, DECT, IMT-2020, interface, MIMO, OFDM,
radio
ETSI
650 Route des Lucioles
F-06921 Sophia Antipolis Cedex - FRANCE

Tel.: [phone]  Fax: [phone]

Siret N° 348 623 562 00017 - NAF 742 C
Association à but non lucratif enregistrée à la
Sous-Préfecture de Grasse (06) N° 7803/88

Important notice
The present document can be downloaded from:
http://www.etsi.org/standards-search
The present document may be made available in electronic versions and/or in print. The content of any electronic and/or
print versions of the present document shall not be modified without the prior written authorization of ETSI. In case of any
existing or perceived difference in contents between such versions and/or in print, the prevailing version of an ETSI
deliverable is the one made publicly available in PDF format at www.etsi.org/deliver.
Users of the present document should be aware that the document may be subject to revision or change of status.
Information on the current status of this and other ETSI documents is available at
https://portal.etsi.org/TB/ETSIDeliverableStatus.aspx
If you find errors in the present document, please send your comment to one of the following services:
https://portal.etsi.org/People/CommiteeSupportStaff.aspx
Copyright Notification
No part may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying
and microfilm except as authorized by written permission of ETSI.
The content of the PDF version shall not be modified without the written authorization of ETSI.
The copyright and the foregoing restriction extend to reproduction in all media.

© ETSI 2019.
All rights reserved.

DECT™, PLUGTESTS™, UMTS™ and the ETSI logo are trademarks of ETSI registered for the benefit of its Members.

3GPP™ and LTE™ are trademarks of ETSI registered for the benefit of its Members and
of the 3GPP Organizational Partners.
oneM2M™ logo is a trademark of ETSI registered for the benefit of its Members and
of the oneM2M Partners.
®
GSM and the GSM logo are trademarks registered and owned by the GSM Association.
ETSI

---------------------- Page: 2 ----------------------
3 ETSI TR 103 635 V1.1.1 (2019-11)
Contents
Intellectual Property Rights . 9
Foreword . 9
Modal verbs terminology . 9
Introduction . 9
1 Scope . 11
2 References . 11
2.1 Normative references . 11
2.2 Informative references . 11
3 Definition of terms, symbols and abbreviations . 13
3.1 Terms . 13
3.2 Symbols . 14
3.3 Abbreviations . 14
4 Introduction to DECT-2020 Use Cases and their Requirements . 18
4.1 Introduction . 18
4.2 Other Design Targets for DECT-2020 . 18
4.3 IMT-2020 scenarios and performance requirements . 18
5 Methodology, initial sources, simulation tools, models and material from the PHY layer . 19
5.1 Initial sources . 19
5.2 Simulation tools . 20
5.3 Channel models . 20
5.4 Channel measurements . 20
5.5 Review of material from the PHY layer . 20
5.5.1 "Standard" frames (long and short variants) . 20
5.5.2 Beacon frames . 21
5.5.3 RAC and ULE frames . 21
5.5.4 HE frames . 21
5.5.5 Items requiring further study . 21
6 Channel Access Concepts for DECT-2020 . 21
6.1 Review of previous design choices . 21
6.2 Possible approaches for the channel access . 22
6.2.1 General . 22
6.2.2 Concept 1: improved WLAN approach . 22
6.2.3 Concept 2: scheduled operation design with complete MAC design . 22
6.2.4 Concept 3: the best of 1 + 2 . 22
6.2.5 Decision and working assumption . 23
6.2.5.1 Working decision on overall channel access concept . 23
6.2.6 Expected spectrum bands . 23
6.2.7 Specifications for channel access and service coexistence . 23
6.3 Void . 24
6.4 Void . 24
6.5 Contribution 1: Channel access for DECT-2020 . 24
6.5.1 Background . 24
6.5.2 DECT "core band" (1 880 MHz - 1 900 MHz) . 25
6.5.3 MAC Channel Access Background . 25
6.5.4 Notes on Last Minute Scanning . 26
6.5.5 Summary of Working Assumptions . 27
6.5.6 Channel Access - Idea 1 . 27
6.5.7 Channel Access - Idea 2 . 29
6.6 Contribution 2: Channel access for DECT-2020 . 31
6.6.1 Aspects to be considered . 31
6.6.2 Proposal . 31
ETSI

---------------------- Page: 3 ----------------------
4 ETSI TR 103 635 V1.1.1 (2019-11)
6.7 Contribution 3: Channel access considerations . 32
7 MAC Protocol Function and PHY Services . 33
7.1 A flexible lower MAC model for DECT-2020. 33
7.1.1 Overview . 33
7.1.2 Types of possible systems . 33
7.1.3 The model "A", an intermediate system operation model suitable for many systems and types of
traffic . 34
7.1.3.1 Design targets . 34
7.1.3.2 The design . 34
7.1.3.3 Remarks . 34
7.1.3.4 Elements taken from other MAC study areas. 34
7.1.3.5 Basic design . 35
7.1.3.6 Broadcast information . 35
7.1.3.7 The message "sequence" . 36
7.1.3.8 Configuration of scheduled services . 36
7.1.4 Slot allocation and message/response sequences . 36
7.1.4.1 Slot allocation . 36
7.1.4.2 Beacon bearers . 36
7.1.4.3 Scheduled services . 36
7.1.4.4 Random Access channels . 36
7.1.4.5 Packed mode traffic - single channel . 36
7.1.4.6 ULE channels . 37
7.1.4.7 Packet mode traffic - wideband . 37
7.1.4.8 Packet mode traffic - downlink packets - Requires further study . 38
7.1.5 Example figure . 39
7.2 Void . 39
7.3 Dual mode solution for the beacon bearer . 39
7.3.1 Summary . 39
7.3.2 Assumptions . 40
7.3.3 Proposal . 40
7.3.3.1 Idea . 40
7.3.3.2 Terminology and tentative construction . 41
7.3.3.3 Structure of the bearer . 41
7.3.3.4 Example of capacity calculation . 41
7.3.3.5 Operation of the bearer and content of the fields . 41
7.3.3.5.1 General . 41
7.3.3.5.2 MAC Information in the "A" field . 42
7.3.3.5.3 MAC Information in the "B" field . 42
7.3.3.5.4 Further ideas on beacon bearer content . 42
7.3.3.6 For further study . 43
7.4 Void . 43
7.5 Latency Considerations . 43
7.5.1 Overview . 43
7.5.2 Control Plane Latency . 43
7.5.3 User Plane Latency . 45
7.6 HARQ . 46
7.6.1 Overview . 46
7.6.1.1 Simple HARQ . 46
7.6.1.2 Hybrid ARQ with "Soft-Combining" . 46
7.6.1.3 "Stop-and-Wait" or "Selective Repeat" . 46
7.6.1.4 "Adaptive Re-transmission" vs "Non-adaptive Re-transmission" . 47
7.6.2 HARQ in DECT-2020 . 47
7.6.3 HARQ Implementation Considerations . 48
7.7 PHL Header Design. 48
7.7.1 Design Rationale . 48
7.7.2 Header Field Contents . 49
7.7.2.1 Header type/version/extension . 49
7.7.2.2 Modulation Coding Scheme (MCS) . 49
7.7.2.3 Number of Spatial Streams . 49
7.7.2.4 Channel Coding Algorithm . 49
7.7.2.5 Transmission Bandwidth . 49
ETSI

---------------------- Page: 4 ----------------------
5 ETSI TR 103 635 V1.1.1 (2019-11)
7.7.2.6 Transmission Length . 50
7.7.2.7 Extras . 50
7.7.2.8 CRC. 50
7.7.3 Header Field Configurations and Size Estimates . 50
7.8 Proposal of unification of the initial part of all random access PHY layer packets and additional
observations on the physical layer . 53
7.8.1 Proposal of modification to the "long format" packet format . 53
7.8.1.1 Rationale . 53
7.8.1.2 Change request to PHY layer . 53
7.8.2 New editorial conventions - position of the inter-slot guard and new A/B terminology . 54
7.8.3 Proposal of extension of the "A" symbols . 54
7.8.4 Further observations to the PHY layer . 55
7.8.4.1 General . 55
7.8.4.2 STF time is perhaps too large . 55
7.8.4.3 CTF time is perhaps too large . 55
7.8.4.4 The current design of the standard long format packets requires knowing the length of the whole
packet at the beginning . 55
7.8.4.5 The current design of the standard long format packet is probably too weak (channel tracking)
for long packets . 55
7.8.4.6 MIMO training in long format is inefficient and does not take into account the available
frequency resolution . 55
7.8.4.7 The current design of the standard short packet contains unnecessary STF and may be optimized . 56
7.9 Proposal for Modified PHL Packet Format and Channel Estimation . 56
7.9.1 Background . 56
7.9.2 Different preambles in different packet types . 56
7.9.3 Optimizing usage of CTF field . 58
7.10 Possible ARQ/HARQ strategies in DECT-2020 . 60
7.10.1 General . 60
7.10.2 Possible ARQ mechanisms . 60
7.10.2.1 General . 60
7.10.2.2 Traditional MAC ARQ . 61
7.10.2.3 Hybrid ARQ . 61
7.10.2.4 Retransmission of the content . 61
7.10.3 Elements to be taken into account in ARQ/HARQ design . 62
7.10.3.1 General . 62
7.10.3.2 The size of the basic unit for retransmission . 62
7.10.3.3 The range of MAC numbering . 62
7.10.3.4 The protection of the MAC numbering . 62
7.10.3.5 The identities of the transmitter/receiver and their protection . 62
7.10.4 A possible design approach . 63
7.10.4.1 General . 63
7.10.4.2 Solutions for scheduled traffic . 63
7.10.4.2.1 General . 63
7.10.4.2.2 Example scenario. 63
7.10.4.2.3 Discussion on the scenario . 64
7.10.4.2.4 Simple solution proposed for scheduled traffic . 64
7.10.4.3 Solutions for packet-mode traffic . 65
7.10.4.3.1 General . 65
7.10.4.3.2 Additional considerations . 65
7.10.4.3.3 Possible approaches for L-S approach . 66
7.10.4.3.4 Possible approaches for I-C-O approach . 67
8 Protocol Stack Architecture . 67
8.1 Introduction . 67
8.2 Concept 1. 68
8.2.1 Overall Protocol Stack . 68
8.2.2 Protocol Functions . 69
8.2.2.1 General . 69
8.2.2.2 Convergence layer . 69
8.2.2.3 Routing layer . 69
8.2.2.4 Link control layer . 69
8.2.2.5 MAC . 70
ETSI

---------------------- Page: 5 ----------------------
6 ETSI TR 103 635 V1.1.1 (2019-11)
8.2.3 Layer 2 Protocol Details/Considerations for Mesh Operation . 70
8.2.3.1 MAC functions and PDU format . 70
8.2.3.2 Routing layer .
...