VHF air-ground Digital Link (VDL) Mode 4 radio equipment; Technical characteristics and methods of measurement for ground-based equipment; Part 4: Point-to-point functions

REN/AERO-00020-4

Radijska oprema za digitalno povezavo VHF zrak-tla, 4. način - Tehnične karakteristike in merilne metode za talno opremo - 4. del: Funkcije sistema točka-točka

Ta dokument se uporablja za radijsko opremo naslednjih vrst:
1) talne radijske oddajnike in sprejemnike za zelo visokofrekvenčno (VHF) digitalno povezavo (VDL) za komunikacije zrak-tla, 4. način, ki delujejo v pasu VHF z uporabo modulacije frekvenčnega premičnega kodiranja prek filtra Gaussian (GFSK) z razmikom 25 kHz med kanali in so zmožni uravnavati na katerem koli izmed kanalov 25 kHz od 112,000 MHz do 136,975 MHz, kot je opredeljeno v standardih in priporočenih praksah (SARP) [7] za digitalne povezave ICAO VHF (VDL).
Ta dokument vsebuje 4. del tehničnih specifikacij.
Ta dokument zagotavlja, da bo oprema, ki bo certificirana v skladu z njim, združljiva z ustreznimi standardi in priporočenimi praksami (SARP) [7] za digitalne povezave ICAO VHF (VDL) in tehničnim priročnikom ICAO za digitalno povezavo VDL, 4. način (TM) [1].
Proizvajalci naj bodo pozorni, da razpon uravnavanja za talne oddajnike-sprejemnike lahko v prihodnje zajema tudi kateri koli kanal 25 kHz od 108,000 MHz do 111,975 MHz.
Področje uporabe tega dokumenta je omejeno na zemeljske postaje. Enakovredna specifikacija za letalske postaje je ETSI EN 302 842 [i.1].
Opis področja uporabe sistema VDL, 4. način, je naveden v 2. delu teh tehničnih specifikacij (glej ETSI EN 301 842-2 [5], 1. točka).
Standard ETSI EN 301 842-1 [4] obravnava preskuse fizične plasti, standard ETSI EN 301 842-2 [5] obravnava temeljno funkcionalnost podatkovne povezave, standard ETSI EN 301 842-3 [6] pa dodatno funkcionalnost v zvezi z radiodifuzijo. Ta dokument zajema preskuse
plasti za podatkovne povezave (DLS) in plasti povezav, ki zadostujejo za podporo funkcij točka-točka.
Ta dokument je organiziran na naslednji način:
• točka 2 vsebuje sklice do ustreznih dokumentov;
• točka 3 vsebuje splošne opredelitve, kratice in simbole, ki se uporabljajo;
• točka 4 vsebuje funkcije točka-točka zemeljske postaje VDL, 4. način;
• točka 5 vsebuje specifikacije lastnosti zemeljskih postaj VDL, 4. način;
• točka 6 vsebuje splošne zahteve projekta;
• točka 7 vsebuje preskuse protokolov za funkcije točka-točka sistema;
• dodatek A vsebuje podrobne sklice do ustreznih zahtev, ki so vključene v [1];
• dodatek B vsebuje bibliografijo.
Upoštevati je treba, da lahko sistem podpira zelo širok nabor funkcij. Podajanje določenih preskusov za celoten nabor funkcij ni praktično. Tako so podani podrobni preskusi za osrednje funkcije točka-točka in preskusi tistih preostalih zahtev, ki lahko v primeru nepravilnega izvajanja povzročijo poslabšanje storitve, ki jo zagotavljajo druge postaje VDL, 4. način.
Izražanje zahtev in priporočil
a) »Je treba«:
– uporaba izraza »je treba« pomeni obvezno merilo, tj. skladnost z določenim postopkom ali specifikacijo je nujna, pri čemer uporaba alternativ ni dovoljena.
b) »Naj bi«:
– uporaba izraza »naj bi« (in izrazov, kot je »priporočljivo je, da ...« itd.) pomeni, da se lahko namesto postopka ali merila, ki je sicer obravnavano kot prednostno, uporabijo tudi alternativni postopki, specifikacije ali merila, če lahko proizvajalec, monter ali preizkuševalec zagotovi informacije ali podatke, ki ustrezno podpirajo in upravičujejo alternativo

General Information

Status
Published
Publication Date
12-Apr-2015
Technical Committee
Current Stage
12 - Completion
Due Date
20-Apr-2015
Completion Date
13-Apr-2015

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ETSI EN 301 842-4 V1.3.1 (2015-04) - VHF air-ground Digital Link (VDL) Mode 4 radio equipment; Technical characteristics and methods of measurement for ground-based equipment; Part 4: Point-to-point functions
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2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.KQLþQHWRþNDVHF air-ground Digital Link (VDL) Mode 4 radio equipment; Technical characteristics and methods of measurement for ground-based equipment; Part 4: Point-to-point functions49.090On-board equipment and instruments33.060.99Druga oprema za radijske komunikacijeOther equipment for radiocommunicationsICS:Ta slovenski standard je istoveten z:EN 301 842-4 V1.3.1SIST EN 301 842-4 V1.3.1:2015en,fr,de01-oktober-2015SIST EN 301 842-4 V1.3.1:2015SLOVENSKI
STANDARD



SIST EN 301 842-4 V1.3.1:2015



ETSI EN 301 842-4 V1.3.1 (2015-04) VHF air-ground Digital Link (VDL) Mode 4 radio equipment; Technical characteristics and methods of measurement for ground-based equipment; Part 4: Point-to-point functions
EUROPEAN STANDARD SIST EN 301 842-4 V1.3.1:2015



ETSI ETSI EN 301 842-4 V1.3.1 (2015-04) 2
Reference REN/AERO-00020-4 Keywords aeronautical, digital, radio, testing, VHF ETSI 650 Route des Lucioles F-06921 Sophia Antipolis Cedex - FRANCE
Tel.: +33 4 92 94 42 00
Fax: +33 4 93 65 47 16
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 only prevailing document is the print of the Portable Document Format (PDF) version kept on a specific network drive within ETSI Secretariat. 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 http://portal.etsi.org/tb/status/status.asp 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.
© European Telecommunications Standards Institute 2015. All rights reserved.
DECTTM, PLUGTESTSTM, UMTSTM and the ETSI logo are Trade Marks of ETSI registered for the benefit of its Members. 3GPPTM and LTE™ are Trade Marks of ETSI registered for the benefit of its Members and of the 3GPP Organizational Partners. GSM® and the GSM logo are Trade Marks registered and owned by the GSM Association. SIST EN 301 842-4 V1.3.1:2015



ETSI ETSI EN 301 842-4 V1.3.1 (2015-04) 3 Contents Intellectual Property Rights . 6 Foreword . 6 Modal verbs terminology . 6 Introduction . 7 1 Scope . 8 2 References . 9 2.1 Normative references . 9 2.2 Informative references . 9 3 Definitions and abbreviations . 10 3.1 Definitions . 10 3.1.1 Basic reference model definitions . 10 3.1.2 Service conventions definitions . 10 3.1.3 General definitions . 10 3.1.4 Definition of bit order . 10 3.2 Abbreviations . 10 4 General description of VDL Mode 4 ground station point-to-point services . 11 4.1 General . 11 4.2 Data Link Service (DLS) and Link Management Entity (LME) . 12 4.2.1 General . 12 4.2.2 DLS timers . 15 4.2.3 DLS counters . 15 4.2.4 Toggle bit (T) . 15 4.2.5 State variables (Tt and Tr) . 16 4.2.6 Initialize Bit (IB) . 16 4.2.7 More bit (M) . 16 4.2.8 Priority (pr) . 16 4.2.9 Message fragmentation and concatenation . 16 4.2.10 DLS procedures . 16 4.2.10.1 Selection of DLS procedures. 16 4.2.10.2 Short transmission procedures . 17 4.2.10.3 Long transmission procedures . 17 4.2.11 Linking transmissions . 19 4.2.11.1 Types of linking . 19 4.2.11.2 Combined RTS / DATA DLPDUs . 19 4.2.11.3 Combined DATA / ACK DLPDUs . 19 4.2.11.4 Combined RTS / ACK DLPDUs . 19 4.2.11.5 Combined CTS / ACK DLPDUs . 19 4.2.12 Ground-air link management . 19 4.2.13 Air-air link management . 20 4.3 Additional VSS Services . 20 5 Minimum performance specification under standard test conditions . 20 5.1 DLS Sublayer . 20 5.1.1 General . 20 5.1.1.1 Services . 20 5.1.1.2 Data transfer . 21 5.1.1.3 DATA DLPDU duplicate suppression and sequencing . 21 5.1.1.4 Error detection . 21 5.1.1.5 Station identification . 21 5.1.1.6 Broadcast addressing . 21 5.1.1.7 DLS Priority . 22 5.1.1.8 DLS Link control DLPDUs . 22 5.1.2 DLS protocol specification . 22 5.1.2.1 State Variables . 22 SIST EN 301 842-4 V1.3.1:2015



ETSI ETSI EN 301 842-4 V1.3.1 (2015-04) 4 5.1.2.2 DLS burst formats . 22 5.1.3 DLS system parameters . 26 5.1.4 DLS procedures . 27 5.1.4.1 Setting of re-transmission parameter . 27 5.1.4.2 Selection of user data packet for transmission . 28 5.1.4.3 Selection of transmission procedures . 29 5.1.4.4 Short transmission procedures . 30 5.1.4.5 Long transmission procedures . 31 5.1.4.6 No link with sender . 33 5.1.4.7 User data packet reception . 34 5.1.4.8 Receipt of ACK DLPDU . 34 5.1.4.9 Link reset . 35 5.1.4.10 Linking DLS DLPDU transmissions . 35 5.1.4.11 CTRL DLPDU . 36 5.2 Link management entity sublayer. 36 5.2.1 Services . 36 5.2.1.1 General . 36 5.2.1.2 Link provision . 37 5.2.1.3 Link change notifications . 37 5.2.1.4 CTRL DLPDU . 37 5.2.1.5 Broadcast link management burst . 38 5.2.2 Control (CTRL) parameter formats . 38 5.2.2.1 Encoding . 38 5.2.2.2 General purpose information parameters . 38 5.2.2.3 Mobile-initiated information parameters . 42 5.2.2.4 Ground-initiated modification parameters . 43 5.2.2.5 Ground-initiated information parameters . 46 5.2.3 LME timers and parameters . 48 5.2.3.1 General . 48 5.2.3.2 Timer TL1 (maximum link overlap time) . 49 5.2.3.3 Parameters TL2 (link initialization time) . 49 5.2.3.4 Timer TL4 (leave generation latency) . 49 5.2.4 CTRL DLPDU types and procedures . 50 5.2.5 CTRL transmission procedures . 53 5.2.5.1 Link connectivity procedures . 53 5.2.5.2 Ground Station Identification . 53 5.2.5.3 Link establishment . 53 5.2.5.4 Mobile-initiated handoff . 54 5.2.5.5 Mobile-requested ground-initiated handoff . 54 5.2.5.6 Ground-initiated handoff . 55 5.2.5.7 Ground-requested mobile-initiated handoff . 55 5.2.5.8 Ground-requested broadcast handoff . 55 5.2.5.9 Ground-commanded autotune . 56 5.2.6 VDL Mode 4 Mobile Subnetwork Dependent Convergence Function (SNDCF) . 56 5.2.6.1 Frame Mode SNDCF . 56 5.3 Additional VSS Requirements . 56 5.3.1 Additional VSS quality of service parameters . 56 5.3.1.1 Parameter Q5 (VSS retransmission parameters) . 56 5.3.2 Unicast request protocol specification . 56 5.3.2.1 Unicast request parameters. 57 5.3.2.2 Unicast request transmission procedures . 58 5.3.3 Information transfer request protocol specification . 58 5.3.3.1 Information transfer request parameters . 58 5.3.3.2 Information transfer request transmission procedures . 60 5.3.3.3 Information transfer request acknowledgement procedures . 60 5.3.4 Retransmission procedures . 60 6 General design requirements . 61 7 Protocol test procedures . 61 7.1 General . 61 7.2 Required test rig . 61 SIST EN 301 842-4 V1.3.1:2015



ETSI ETSI EN 301 842-4 V1.3.1 (2015-04) 5 7.3 Protocol test-suite description methodology . 61 7.4 Detailed protocol test procedures . 62 7.4.1 Test-suite overview . 62 7.4.2 Declarations . 64 7.4.3 Constraints . 64 7.4.3.1 Abbreviations . 64 7.4.3.1.1 Subfield mnemonics . 64 7.4.3.1.2 Special characters used in the subfield definitions . 65 7.4.3.1.3 Station addresses and positions . 65 7.4.3.1.4 VDL bursts . 66 7.4.3.2 Test cases . 96 7.4.3.2.1 Test case macros . 97 7.4.3.2.2 Test case descriptions . 99 Annex A (informative): Cross reference matrix . 154 Annex B (informative): Bibliography . 163 History . 164
SIST EN 301 842-4 V1.3.1:2015



ETSI ETSI EN 301 842-4 V1.3.1 (2015-04) 6 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 (http://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 European Standard (EN) has been produced by ETSI Technical Committee Aeronautics (AERO). The present document is part 4 of a multi-part deliverable covering the VHF air-ground Digital Link (VDL) Mode 4 radio equipment; Technical characteristics and methods of measurement for ground-based equipment, as identified below: Part 1: "EN for ground equipment"; Part 2: "General description and data link layer"; Part 3: "Additional broadcast aspects"; Part 4: "Point-to-point functions"; Part 5: "Hamonized EN covering the essential requirements of article 3.2 of the R&TTE Directive". The present document is accompanied by an equivalent airborne standard, ETSI EN 302 842 [i.1] Parts 1 to 4, covering the VHF air-ground Digital Link (VDL) Mode 4 radio equipment; Technical characteristics and methods of measurement for airborne equipment.
National transposition dates Date of adoption of this EN: 6 April 2015 Date of latest announcement of this EN (doa): 31 July 2015 Date of latest publication of new National Standard or endorsement of this EN (dop/e):
31 January 2016 Date of withdrawal of any conflicting National Standard (dow): 31 January 2017
Modal verbs terminology In the present document "shall", "shall not", "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. SIST EN 301 842-4 V1.3.1:2015



ETSI ETSI EN 301 842-4 V1.3.1 (2015-04) 7 Introduction The present document states the technical specifications for Very High Frequency (VHF) Digital Link (VDL) Mode 4 ground-based radio transmitters, transceivers and receivers for air-ground communications operating in the VHF band, using Gaussian-filtered Frequency Shift Keying (GFSK) Modulation with 25 kHz channel spacing and capable of tuning to any of the 25 kHz channels from 112,000 MHz to 136,975 MHz as defined in ICAO VHF Digital Link (VDL) Standards and Recommended Practices (SARPs) [7]. The present document may be used to produce tests for the assessment of the performance of the equipment.
SIST EN 301 842-4 V1.3.1:2015



ETSI ETSI EN 301 842-4 V1.3.1 (2015-04) 8 1 Scope The present document applies to the following radio equipment types: 1) Very High Frequency (VHF) Digital Link (VDL) Mode 4 ground-based radio transmitters and receivers for air-ground communications operating in the VHF band, using Gaussian-filtered Frequency Shift Keying (GFSK) Modulation with 25 kHz channel spacing and capable of tuning to any of the 25 kHz channels from 112,000 MHz to 136,975 MHz as defined in ICAO VHF Digital Link (VDL) Standards and Recommended Practices (SARPs) [7]. The present document provides part 4 of the technical specifications. The present document is designed to ensure that equipment certified to it will be compatible with the relevant ICAO VHF Digital Link (VDL) Standards and Recommended Practices (SARPs) [7] and VDL Mode 4 Technical Manual (TM) [1]. Manufacturers should note that in future the tuning range for the ground transceivers may also cover any 25 kHz channel from 108,000 MHz to 111,975 MHz. The scope of the present document is limited to ground stations. The equivalent specification for airborne stations is
ETSI EN 302 842 [i.1]. A description of the scope of the VDL Mode 4 system is provided in part 2 of these technical specifications (see ETSI EN 301 842-2 [5], clause 1). ETSI EN 301 842-1 [4] deals with tests of the physical layer, ETSI EN 301 842-2 [5] deals with core link layer functionality and ETSI EN 301 842-3 [6] with additional broadcast functionality. The present document deals with tests of the datalink service (DLS) layer and the link layer sufficient to support point-to-point functionality. The present document is organized as follows: • clause 2 provides references to relevant documents; • clause 3 provides general definitions, abbreviations and symbols used; • clause 4 describes the VDL Mode 4 ground station point-to-point functions; • clause 5 provides performance specifications for the VDL Mode 4 ground station; • clause 6 provides general design requirements; • clause 7 provides protocol tests for the point-to-point functions of the system; • annex A provides a detailed cross-reference to the relevant requirements contained in [1]; • annex B provides a Bibliography. Note that the system can support a very wide range of functions. It is not practical to provide specific tests for all aspects of functionality. The approach used is to provide detailed tests for the core point-to-point functionality and to provide tests of those remaining requirements which, if wrongly implemented, could cause a deterioration in the service offered by other VDL Mode 4 stations. Mandating and Recommendation Phrases a) "Shall": - the use of the word "Shall" indicates a mandated criterion; i.e. compliance with the particular procedure or specification is mandatory and no alternative may be applied. b) "Should": - the use of the word "Should" (and phrases such as "It is recommended that.", etc.) indicates that though the procedure or criterion is regarded as the preferred option, alternative procedures, specifications or criteria may be applied, provided that the manufacturer, installer or tester can provide information or data to adequately support and justify the alternative. SIST EN 301 842-4 V1.3.1:2015



ETSI ETSI EN 301 842-4 V1.3.1 (2015-04) 9 2 References 2.1 Normative references References are either specific (identified by date of publication and/or edition number or version number) or non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the referenced doc
...

ETSI EN 301 842-4 V1.3.1 (2015-04)






EUROPEAN STANDARD
VHF air-ground Digital Link (VDL) Mode 4 radio equipment;
Technical characteristics and methods of measurement
for ground-based equipment;
Part 4: Point-to-point functions

---------------------- Page: 1 ----------------------
2 ETSI EN 301 842-4 V1.3.1 (2015-04)



Reference
REN/AERO-00020-4
Keywords
aeronautical, digital, radio, testing, VHF
ETSI
650 Route des Lucioles
F-06921 Sophia Antipolis Cedex - FRANCE

Tel.: +33 4 92 94 42 00  Fax: +33 4 93 65 47 16

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 only prevailing document is the
print of the Portable Document Format (PDF) version kept on a specific network drive within ETSI Secretariat.
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
http://portal.etsi.org/tb/status/status.asp
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.

© European Telecommunications Standards Institute 2015.
All rights reserved.

TM TM TM
DECT , PLUGTESTS , UMTS and the ETSI logo are Trade Marks of ETSI registered for the benefit of its Members.
TM
3GPP and LTE™ are Trade Marks of ETSI registered for the benefit of its Members and
of the 3GPP Organizational Partners.
GSM® and the GSM logo are Trade Marks registered and owned by the GSM Association.
ETSI

---------------------- Page: 2 ----------------------
3 ETSI EN 301 842-4 V1.3.1 (2015-04)
Contents
Intellectual Property Rights . 6
Foreword . 6
Modal verbs terminology . 6
Introduction . 7
1 Scope . 8
2 References . 9
2.1 Normative references . 9
2.2 Informative references . 9
3 Definitions and abbreviations . 10
3.1 Definitions . 10
3.1.1 Basic reference model definitions . 10
3.1.2 Service conventions definitions . 10
3.1.3 General definitio ns . 10
3.1.4 Definition of bit order . 10
3.2 Abbreviations . 10
4 General description of VDL Mode 4 ground station point-to-point services . 11
4.1 General . 11
4.2 Data Link Service (DLS) and Link Management Entity (LME) . 12
4.2.1 General . 12
4.2.2 DLS timers . 15
4.2.3 DLS counters . 15
4.2.4 Toggle bit (T) . 15
4.2.5 State variables (T and T ) . 16
t r
4.2.6 Initialize Bit (IB) . 16
4.2.7 More bit (M) . 16
4.2.8 Priority (pr) . 16
4.2.9 Message fragmentation and concatenation . 16
4.2.10 DLS procedures . 16
4.2.10.1 Selection of DLS procedures. 16
4.2.10.2 Short transmission procedures . 17
4.2.10.3 Long transmission procedures . 17
4.2.11 Linking transmissions . 19
4.2.11.1 Types of linking . 19
4.2.11.2 Combined RTS / DATA DLPDUs . 19
4.2.11.3 Combined DATA / ACK DLPDUs . 19
4.2.11.4 Combined RTS / ACK DLPDUs . 19
4.2.11.5 Combined CTS / ACK DLPDUs . 19
4.2.12 Ground-air link management . 19
4.2.13 Air-air link management . 20
4.3 Additional VSS Services . 20
5 Minimum performance specification under standard test conditions . 20
5.1 DLS Sublayer . 20
5.1.1 General . 20
5.1.1.1 Services . 20
5.1.1.2 Data transfer . 21
5.1.1.3 DATA DLPDU duplicate suppression and sequencing . 21
5.1.1.4 Error detection . 21
5.1.1.5 Station identification . 21
5.1.1.6 Broadcast addressing . 21
5.1.1.7 DLS Priority . 22
5.1.1.8 DLS Link control DLPDUs . 22
5.1.2 DLS protocol specification . 22
5.1.2.1 State Variables . 22
ETSI

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4 ETSI EN 301 842-4 V1.3.1 (2015-04)
5.1.2.2 DLS burst formats . 22
5.1.3 DLS system parameters . 26
5.1.4 DLS procedures . 27
5.1.4.1 Setting of re-transmission parameter . 27
5.1.4.2 Selection of user data packet for transmission . 28
5.1.4.3 Selection of transmission procedures . 29
5.1.4.4 Short transmission procedures . 30
5.1.4.5 Long transmission procedures . 31
5.1.4.6 No link with sender . 33
5.1.4.7 User data packet reception . 34
5.1.4.8 Receipt of ACK DLPDU . 34
5.1.4.9 Link reset . 35
5.1.4.10 Linking DLS DLPDU transmissions . 35
5.1.4.11 CTRL DLPDU . 36
5.2 Link management entity sublayer. 36
5.2.1 Services . 36
5.2.1.1 General . 36
5.2.1.2 Link provision . 37
5.2.1.3 Link change notifications . 37
5.2.1.4 CTRL DLPDU . 37
5.2.1.5 Broadcast link management burst . 38
5.2.2 Control (CTRL) parameter formats . 38
5.2.2.1 Encoding . 38
5.2.2.2 General purpose information parameters . 38
5.2.2.3 Mobile-initiated information parameters . 42
5.2.2.4 Ground-initiated modification parameters . 43
5.2.2.5 Ground-initiated information parameters . 46
5.2.3 LME timers and parameters . 48
5.2.3.1 General . 48
5.2.3.2 Timer TL1 (maximum link overlap time) . 49
5.2.3.3 Parameters TL2 (link initialization time) . 49
5.2.3.4 Timer TL4 (leave generation latency) . 49
5.2.4 CTRL DLPDU types and procedures . 50
5.2.5 CTRL transmission procedures . 53
5.2.5.1 Link connectivity procedures . 53
5.2.5.2 Ground Station Identification . 53
5.2.5.3 Link establishment . 53
5.2.5.4 Mobile-initiated handoff . 54
5.2.5.5 Mobile-requested ground-initiated handoff . 54
5.2.5.6 Ground-initiated handoff . 55
5.2.5.7 Ground-requested mobile-initiated handoff . 55
5.2.5.8 Ground-requested broadcast handoff . 55
5.2.5.9 Ground-commanded autotune . 56
5.2.6 VDL Mode 4 Mobile Subnetwork Dependent Convergence Function (SNDCF) . 56
5.2.6.1 Frame Mode SNDCF . 56
5.3 Additional VSS Requirements . 56
5.3.1 Additional VSS quality of service parameters . 56
5.3.1.1 Parameter Q5 (VSS retransmission parameters) . 56
5.3.2 Unicast request protocol specification . 56
5.3.2.1 Unicast request parameters. 57
5.3.2.2 Unicast request transmission procedures . 58
5.3.3 Information transfer request protocol specification . 58
5.3.3.1 Information transfer request parameters . 58
5.3.3.2 Information transfer request transmission procedures . 60
5.3.3.3 Information transfer request acknowledgement procedures . 60
5.3.4 Retransmission procedures . 60
6 General design requirements . 61
7 Protocol test procedures . 61
7.1 General . 61
7.2 Required test rig . 61
ETSI

---------------------- Page: 4 ----------------------
5 ETSI EN 301 842-4 V1.3.1 (2015-04)
7.3 Protocol test-suite description methodology . 61
7.4 Detailed protocol test procedures . 62
7.4.1 Test-suite overview . 62
7.4.2 Declarations . 64
7.4.3 Constraints . 64
7.4.3.1 Abbreviations . 64
7.4.3.1.1 Subfield mnemonics . 64
7.4.3.1.2 Special characters used in the subfield definitions . 65
7.4.3.1.3 Station addresses and positions . 65
7.4.3.1.4 VDL bursts . 66
7.4.3.2 Test cases . 96
7.4.3.2.1 Test case macros . 97
7.4.3.2.2 Test case descriptions . 99
Annex A (informative): Cross reference matrix . 154
Annex B (informative): Bibliography . 163
History . 164

ETSI

---------------------- Page: 5 ----------------------
6 ETSI EN 301 842-4 V1.3.1 (2015-04)
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 (http://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 European Standard (EN) has been produced by ETSI Technical Committee Aeronautics (AERO).
The present document is part 4 of a multi-part deliverable covering the VHF air-ground Digital Link (VDL) Mode 4
radio equipment; Technical characteristics and methods of measurement for ground-based equipment, as identified
below:
Part 1: "EN for ground equipment";
Part 2: "General description and data link layer";
Part 3: "Additional broadcast aspects";
Part 4: "Point-to-point functions";
Part 5: "Hamonized EN covering the essential requirements of article 3.2 of the R&TTE Directive".
The present document is accompanied by an equivalent airborne standard, ETSI EN 302 842 [i.1] Parts 1 to 4, covering
the VHF air-ground Digital Link (VDL) Mode 4 radio equipment; Technical characteristics and methods of
measurement for airborne equipment.

National transposition dates
Date of adoption of this EN: 6 April 2015
Date of latest announcement of this EN (doa): 31 July 2015
Date of latest publication of new National Standard
or endorsement of this EN (dop/e): 31 January 2016
Date of withdrawal of any conflicting National Standard (dow): 31 January 2017

Modal verbs terminology
In the present document "shall", "shall not", "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

---------------------- Page: 6 ----------------------
7 ETSI EN 301 842-4 V1.3.1 (2015-04)
Introduction
The present document states the technical specifications for Very High Frequency (VHF) Digital Link (VDL) Mode 4
ground-based radio transmitters, transceivers and receivers for air-ground communications operating in the VHF band,
using Gaussian-filtered Frequency Shift Keying (GFSK) Modulation with 25 kHz channel spacing and capable of
tuning to any of the 25 kHz channels from 112,000 MHz to 136,975 MHz as defined in ICAO VHF Digital Link (VDL)
Standards and Recommended Practices (SARPs) [7].
The present document may be used to produce tests for the assessment of the performance of the equipment.
ETSI

---------------------- Page: 7 ----------------------
8 ETSI EN 301 842-4 V1.3.1 (2015-04)
1 Scope
The present document applies to the following radio equipment types:
1) Very High Frequency (VHF) Digital Link (VDL) Mode 4 ground-based radio transmitters and receivers for
air-ground communications operating in the VHF band, using Gaussian-filtered Frequency Shift Keying (GFSK)
Modulation with 25 kHz channel spacing and capable of tuning to any of the 25 kHz channels from
112,000 MHz to 136,975 MHz as defined in ICAO VHF Digital Link (VDL) Standards and Recommended
Practices (SARPs) [7].
The present document provides part 4 of the technical specifications.
The present document is designed to ensure that equipment certified to it will be compatible with the relevant ICAO
VHF Digital Link (VDL) Standards and Recommended Practices (SARPs) [7] and VDL Mode 4 Technical Manual
(TM) [1].
Manufacturers should note that in future the tuning range for the ground transceivers may also cover any 25 kHz
channel from 108,000 MHz to 111,975 MHz.
The scope of the present document is limited to ground stations. The equivalent specification for airborne stations is
ETSI EN 302 842 [i.1].
A description of the scope of the VDL Mode 4 system is provided in part 2 of these technical specifications
(see ETSI EN 301 842-2 [5], clause 1).
ETSI EN 301 842-1 [4] deals with tests of the physical layer, ETSI EN 301 842-2 [5] deals with core link layer
functionality and ETSI EN 301 842-3 [6] with additional broadcast functionality. The present document deals with tests
of the datalink service (DLS) layer and the link layer sufficient to support point-to-point functionality.
The present document is organized as follows:
• clause 2 provides references to relevant documents;
• clause 3 provides general definitions, abbreviations and symbols used;
• clause 4 describes the VDL Mode 4 ground station point-to-point functions;
• clause 5 provides performance specifications for the VDL Mode 4 ground station;
• clause 6 provides general design requirements;
• clause 7 provides protocol tests for the point-to-point functions of the system;
• annex A provides a detailed cross-reference to the relevant requirements contained in [1];
• annex B provides a Bibliography.
Note that the system can support a very wide range of functions. It is not practical to provide specific tests for all
aspects of functionality. The approach used is to provide detailed tests for the core point-to-point functionality and
to provide tests of those remaining requirements which, if wrongly implemented, could cause a deterioration in the
service offered by other VDL Mode 4 stations.
Mandating and Recommendation Phrases
a) "Shall":
- the use of the word "Shall" indicates a mandated criterion; i.e. compliance with the particular procedure
or specification is mandatory and no alternative may be applied.
b) "Should":
- the use of the word "Should" (and phrases such as "It is recommended that.", etc.) indicates that though
the procedure or criterion is regarded as the preferred option, alternative procedures, specifications or
criteria may be applied, provided that the manufacturer, installer or tester can provide information or data
to adequately support and justify the alternative.
ETSI

---------------------- Page: 8 ----------------------
9 ETSI EN 301 842-4 V1.3.1 (2015-04)
2 References
2.1 Normative references
References are either specific (identified by date of publication and/or edition number or version number) or
non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the
referenced document (including any amendments) applies.
Referenced documents which are not found to be publicly a
...

Draft ETSI EN 301 842-4 V1.3.0 (2014-12)






EUROPEAN STANDARD
VHF air-ground Digital Link (VDL) Mode 4 radio equipment;
Technical characteristics and methods of measurement
for ground-based equipment;
Part 4: Point-to-point functions

---------------------- Page: 1 ----------------------
2 Draft ETSI EN 301 842-4 V1.3.0 (2014-12)



Reference
REN/AERO-00020-4
Keywords
aeronautical, digital, radio, testing, VHF
ETSI
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Copyright Notification
No part may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying
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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.

© European Telecommunications Standards Institute 2014.
All rights reserved.

TM TM TM
DECT , PLUGTESTS , UMTS and the ETSI logo are Trade Marks of ETSI registered for the benefit of its Members.
TM
3GPP and LTE™ are Trade Marks of ETSI registered for the benefit of its Members and
of the 3GPP Organizational Partners.
GSM® and the GSM logo are Trade Marks registered and owned by the GSM Association.
ETSI

---------------------- Page: 2 ----------------------
3 Draft ETSI EN 301 842-4 V1.3.0 (2014-12)
Contents
Intellectual Property Rights . 6
Foreword . 6
Modal verbs terminology . 6
Introduction . 7
1 Scope . 8
2 References . 9
2.1 Normative references . 9
2.2 Informative references . 10
3 Definitions and abbreviations . 10
3.1 Definitions . 10
3.1.1 Basic reference model definitions . 10
3.1.2 Service conventions definitions . 10
3.1.3 General definitio ns . 10
3.1.4 Definition of bit order . 10
3.2 Abbreviations . 11
4 General description of VDL Mode 4 ground station point-to-point services . 12
4.1 General . 12
4.2 Data Link Service (DLS) and Link Management Entity (LME) . 12
4.2.1 General . 12
4.2.2 DLS timers . 15
4.2.3 DLS counters . 15
4.2.4 Toggle bit (T) . 16
4.2.5 State variables (T and T ) . 16
t r
4.2.6 Initialize Bit (IB) . 16
4.2.7 More bit (M) . 16
4.2.8 Priority (pr) . 16
4.2.9 Message fragmentation and concatenation . 17
4.2.10 DLS procedures . 17
4.2.10.1 Selection of DLS procedures. 17
4.2.10.2 Short transmission procedures . 17
4.2.10.3 Long transmission procedures . 18
4.2.11 Linking transmissions . 19
4.2.11.1 Types of linking . 19
4.2.11.2 Combined RTS / DATA DLPDUs . 19
4.2.11.3 Combined DATA / ACK DLPDUs . 20
4.2.11.4 Combined RTS / ACK DLPDUs . 20
4.2.11.5 Combined CTS / ACK DLPDUs . 20
4.2.12 Ground-air link management . 20
4.2.13 Air-air link management . 20
4.3 Additional VSS Services . 20
5 Minimum performance specification under standard test conditions . 21
5.1 DLS Sublayer . 21
5.1.1 General . 21
5.1.1.1 Services . 21
5.1.1.2 Data transfer . 21
5.1.1.3 DATA DLPDU duplicate suppression and sequencing . 22
5.1.1.4 Error detection . 22
5.1.1.5 Station identification . 22
5.1.1.6 Broadcast addressing . 22
5.1.1.7 DLS Priority . 22
5.1.1.8 DLS Link control DLPDUs . 23
5.1.2 DLS protocol specification . 23
ETSI

---------------------- Page: 3 ----------------------
4 Draft ETSI EN 301 842-4 V1.3.0 (2014-12)
5.1.2.1 State Variables . 23
5.1.2.2 DLS burst formats . 23
5.1.3 DLS system parameters . 27
5.1.4 DLS procedures . 27
5.1.4.1 Setting of re-transmission parameter . 27
5.1.4.2 Selection of user data packet for transmission . 28
5.1.4.3 Selection of transmission procedures . 29
5.1.4.4 Short transmission procedures . 30
5.1.4.5 Long transmission procedures . 31
5.1.4.6 No link with sender . 33
5.1.4.7 User data packet reception . 34
5.1.4.8 Receipt of ACK DLPDU . 34
5.1.4.9 Link reset . 35
5.1.4.10 Linking DLS DLPDU transmissions . 35
5.1.4.11 CTRL DLPDU . 36
5.2 Link management entity sublayer. 36
5.2.1 Services . 36
5.2.1.1 General . 36
5.2.1.2 Link provision . 37
5.2.1.3 Link change notifications . 37
5.2.1.4 CTRL DLPDU . 37
5.2.1.5 Broadcast link management burst . 38
5.2.2 Control (CTRL) parameter formats . 38
5.2.2.1 Encoding . 38
5.2.2.2 General purpose information parameters . 38
5.2.2.3 Mobile-initiated information parameters . 42
5.2.2.4 Ground-initiated modification parameters . 43
5.2.2.5 Ground-initiated information parameters . 46
5.2.3 LME timers and parameters . 48
5.2.3.1 General . 48
5.2.3.2 Timer TL1 (maximum link overlap time) . 49
5.2.3.3 Parameters TL2 (link initialization time) . 49
5.2.3.4 Timer TL4 (leave generation latency) . 49
5.2.4 CTRL DLPDU types and procedures . 50
5.2.5 CTRL transmission procedures . 53
5.2.5.1 Link connectivity procedures . 53
5.2.5.2 Ground Station Identification . 53
5.2.5.3 Link establishment . 53
5.2.5.4 Mobile-initiated handoff . 54
5.2.5.5 Mobile-requested ground-initiated handoff . 54
5.2.5.6 Ground-initiated handoff . 55
5.2.5.7 Ground-requested mobile-initiated handoff . 55
5.2.5.8 Ground-requested broadcast handoff . 55
5.2.5.9 Ground-commanded autotune . 56
5.2.6 VDL Mode 4 Mobile Subnetwork Dependent Convergence Function (SNDCF) . 56
5.2.6.1 Frame Mode SNDCF . 56
5.3 Additional VSS Requirements . 56
5.3.1 Additional VSS quality of service parameters . 56
5.3.1.1 Parameter Q5 (VSS retransmission parameters) . 56
5.3.2 Unicast request protocol specification . 57
5.3.2.1 Unicast request parameters. 57
5.3.2.2 Unicast request transmission procedures . 58
5.3.3 Information transfer request protocol specification . 58
5.3.3.1 Information transfer request parameters . 58
5.3.3.2 Information transfer request transmission procedures . 60
5.3.3.3 Information transfer request acknowledgement procedures . 60
5.3.4 Retransmission procedures . 60
6 General design requirements . 61
7 Protocol test procedures . 61
7.1 General . 61
ETSI

---------------------- Page: 4 ----------------------
5 Draft ETSI EN 301 842-4 V1.3.0 (2014-12)
7.2 Required test rig . 61
7.3 Protocol test-suite description methodology . 62
7.4 Detailed protocol test procedures . 62
7.4.1 Test-suite overview . 62
7.4.2 Declarations . 64
7.4.3 Constraints . 64
7.4.3.1 Abbreviations . 64
7.4.3.1.1 Subfield mnemonics . 64
7.4.3.1.2 Special characters used in the subfield definitions . 65
7.4.3.1.3 Station addresses and positions . 65
7.4.3.1.4 VDL bursts . 66
7.4.3.2 Test cases . 96
7.4.3.2.1 Test case macros . 97
7.4.3.2.2 Test case descriptions . 99
Annex A (informative): Cross reference matrix . 154
Annex B (informative): Bibliography . 163
History . 164

ETSI

---------------------- Page: 5 ----------------------
6 Draft ETSI EN 301 842-4 V1.3.0 (2014-12)
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 (http://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 draft European Standard (EN) has been produced by ETSI Technical Committee Aeronautics (AERO), and is now
submitted for the combined Public Enquiry and Vote phase of the ETSI standards EN Approval Procedure.
The present document is part 4 of a multi-part deliverable covering the VHF air-ground Digital Link (VDL) Mode 4
radio equipment; Technical characteristics and methods of measurement for ground-based equipment, as identified
below:
Part 1: "EN for ground equipment";
Part 2: "General description and data link layer";
Part 3: "Additional broadcast aspects";
Part 4: "Point-to-point functions";
Part 5: "Hamonized EN covering the essential requirements of article 3.2 of the R&TTE Directive".
The present document is accompanied by an equivalent airborne standard, ETSI EN 302 842 [i.1] Parts 1 to 4, covering
the VHF air-ground Digital Link (VDL) Mode 4 radio equipment; Technical characteristics and methods of
measurement for airborne equipment.

Proposed national transposition dates
Date of latest announcement of this EN (doa): 3 months after ETSI publication
Date of latest publication of new National Standard
or endorsement of this EN (dop/e): 6 months after doa
Date of withdrawal of any conflicting National Standard (dow): 18 months after doa

Modal verbs terminology
In the present document "shall", "shall not", "should", "should not", "may", "may not", "need", "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

---------------------- Page: 6 ----------------------
7 Draft ETSI EN 301 842-4 V1.3.0 (2014-12)
Introduction
The present document states the technical specifications for Very High Frequency (VHF) Digital Link (VDL) Mode 4
ground-based radio transmitters, transceivers and receivers for air-ground communications operating in the VHF band,
using Gaussian-filtered Frequency Shift Keying (GFSK) Modulation with 25 kHz channel spacing and capable of
tuning to any of the 25 kHz channels from 112,000 MHz to 136,975 MHz as defined in ICAO VHF Digital Link (VDL)
Standards and Recommended Practices (SARPs) [7].
The present document may be used to produce tests for the assessment of the performance of the equipment.
ETSI

---------------------- Page: 7 ----------------------
8 Draft ETSI EN 301 842-4 V1.3.0 (2014-12)
1 Scope
The present document applies to the following radio equipment types:
1) Very High Frequency (VHF) Digital Link (VDL) Mode 4 ground-based radio transmitters and receivers for
air-ground communications operating in the VHF band, using Gaussian-filtered Frequency Shift Keying (GFSK)
Modulation with 25 kHz channel spacing and capable of tuning to any of the 25 kHz channels from
112,000 MHz to 136,975 MHz as defined in ICAO VHF Digital Link (VDL) Standards and Recommended
Practices (SARPs) [7].
The present document provides part 4 of the technical specifications.
The present document is designed to ensure that equipment certified to it will be compatible with the relevant ICAO
VHF Digital Link (VDL) Standards and Recommended Practices (SARPs) [7] and VDL Mode 4 Technical Manual
(TM) [1].
Manufacturers should note that in future the tuning range for the ground transceivers may also cover any 25 kHz
channel from 108,000 MHz to 111,975 MHz.
The scope of the present document is limited to ground stations. The equivalent specification for airborne stations is
ETSI EN 302 842 [i.1].
A description of the scope of the VDL Mode 4 system is provided in part 2 of these technical specifications
(see ETSI EN 301 842-2 [5], clause 1).
ETSI EN 301 842-1 [4] deals with tests of the physical layer, ETSI EN 301 842-2 [5] deals with core link layer
functionality and ETSI EN 301 842-3 [6] with additional broadcast functionality. The present document deals with tests
of the datalink service (DLS) layer and the link layer sufficient to support point-to-point functionality.
The present document is organized as follows:
• clause 2 provides references to relevant documents;
• clause 3 provides general definitions, abbreviations and symbols used;
• clause 4 describes the VDL Mode 4 ground station point-to-point functions;
• clause 5 provides performance specifications for the VDL Mode 4 ground station;
• clause 6 provides general design requirements;
• clause 7 provides protocol tests for the point-to-point functions of the system;
• annex A provides a detailed cross-reference to the relevant requirements contained in [1];
• annex B provides a Bibliography.
Note that the system can support a very wide range of functions. It is not practical to provide specific tests for all
aspects of functionality. The approach used is to provide detailed tests for the core point-to-point functionality and
to provide tests of those remaining requirements which, if wrongly implemented, could cause a deterioration in the
service offered by other VDL Mode 4 stations.
ETSI

---------------------- Page: 8 ----------------------
9 Draft ETSI EN 301 842-4 V1.3.0 (2014-12)
Mandating and Recommendation Phrases
a) "Shall":
- the use of the word "Shall" indicates a mandated criterion; i.e. compliance with the particular procedure
or specification is mandatory and no alternative may be applied.
b) "Should":
- the use of the word "Should" (and phrases such as "It is recommended that.", etc.) indicates that though
the procedure or criterion is regarded as the preferred option, alternative procedures, specifications or
criteria may be applied, provided that the manufacturer, installer or tester can provide information or data
to adequately support and justify the alternative.
2 References
References are either specific (identified by date of publication and/or edition number or version number) or
non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the
refer
...

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