SIST EN 301 842-1 V1.1.1:2003

SLOVENSKI STANDARD
01-april-2003
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Electromagnetic compatibility and Radio spectrum Matters (ERM); VHF air-ground Data
Link (VDL) Mode 4 radio equipment; Technical characteristics and methods of
measurement for ground-based equipment; Part 1: General description and physical
layer
Ta slovenski standard je istoveten z: EN 301 842-1 Version 1.1.1
ICS:
33.060.99 Druga oprema za radijske Other equipment for
komunikacije radiocommunications
33.100.01 Elektromagnetna združljivost Electromagnetic compatibility
na splošno in general
35.100.10 )L]LþQLVORM Physical layer
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

European Standard (Telecommunications series)

Electromagnetic compatibility
and Radio spectrum Matters (ERM);
VHF air-ground Data Link (VDL)
Mode 4 radio equipment;
Technical characteristics and
methods of measurement
for ground-based equipment;
Part 1: General description and physical layer

2 ETSI EN 301 842-1 V1.1.1 (2002-01)

Reference
DEN/ERM-RP05-016-1
Keywords
aeronautical, digital, radio, testing, VHF
ETSI
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© European Telecommunications Standards Institute 2002.
All rights reserved.
ETSI
3 ETSI EN 301 842-1 V1.1.1 (2002-01)
Contents
Intellectual Property Rights.6
Foreword.6
Introduction .6
1 Scope.8
2 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
3.2 Abbreviations.14
4 General description and architecture of VDL Mode 4 .15
4.1 General.15
4.2 Relationship to OSI reference model.17
4.3 Communication services.18
4.4 ADS-B.18
4.5 Operational scenarios.19
4.6 VDL Mode 4 fundamentals.19
4.7 VDL Mode 4 Ground architecture .20
5 VDL mode 4 physical layer functional specifications .20
5.1 Overview.20
5.1.1 Functions.20
5.1.2 Data reception.20
5.1.3 Data transmission.20
5.2 Modulation scheme.20
5.3 Tuning range and channel increments .20
6 VDL Mode 4 equipment requirements.21
6.1 Receiver Requirements.21
6.1.1 Receiver operating range .21
6.1.2 Sensitivity.21
6.1.3 Adjacent channel rejection.21
6.1.4 Rejection of signals within the VHF Aeronautical band.21
6.1.5 Rejection of signals outside the VHF Aeronautical band.21
6.1.6 Desired signal dynamic range.22
6.1.7 Symbol rate capture range .22
6.1.8 Frequency capture range.22
6.1.9 Co-channel interference.22
6.1.10 Conducted spurious emission .22
6.1.11 In-band Intermodulation.23
6.1.12 Cabinet radiation.23
6.2 Transmitter requirements.23
6.2.1 Protection of the transmitter.23
6.2.2 Manufacturer's declared output power.24
6.2.3 RF power rise time.24
6.2.4 RF power release time .24
6.2.5 Channel bit rate.24
6.2.6 Conducted Spurious emissions .24
6.2.7 Adjacent channel power.25
6.2.8 Wide-band noise.25
6.2.9 Frequency Tolerance.25
6.2.10 Cabinet radiation.25
6.2.11 Load VSWR capability.25
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4 ETSI EN 301 842-1 V1.1.1 (2002-01)
6.3 Transceiver timing requirements.25
6.3.1 Start of transmission .25
6.3.2 Automatic transmitter shutdown.25
6.3.3 Receiver to transmitter turnaround time .25
6.3.4 Transmitter to receiver turnaround time .26
6.3.5 System timing requirements .26
7 General design requirements.26
7.1 Controls and indicators.26
7.2 Class of emission and modulation characteristics .26
7.3 Warm up.26
8 Test conditions, power sources and ambient temperatures .26
8.1 Test power source.26
8.2 Test channels.26
8.3 General conditions of measurement .27
8.3.1 Receiver test signal arrangement .27
8.3.2 Performance check.27
8.4 Normal and extreme test conditions .27
8.4.1 Normal test conditions .27
8.4.1.1 Normal temperature and humidity .27
8.4.1.2 Normal power sources.27
8.4.1.2.1 Mains voltage and frequency.27
8.4.1.2.2 Other power sources .27
8.4.2 Extreme test conditions.27
8.4.2.1 Extreme temperatures.27
8.4.2.2 Procedure for tests at extreme temperatures.28
8.4.2.2.1 General.28
8.4.2.2.2 High temperature.28
8.4.2.2.3 Low temperature.28
8.4.2.3 Extreme values of test power sources .28
8.4.2.3.1 Mains voltage and frequency.28
9 Detailed Test Procedures for the physical layer.28
9.1 Receiver.29
9.1.1 BER test.29
9.1.2 Sensitivity.30
9.1.3 Adjacent Channel Rejection.31
9.1.4 Rejection of signals within the VHF Aeronautical band.31
9.1.5 Rejection of signals outside the VHF Aeronautical band.32
9.1.6 Desired Signal dynamic range .33
9.1.7 Symbol rate capture range .34
9.1.8 Frequency capture range.34
9.1.9 Co-channel interference.35
9.1.10 Conducted spurious emission (clause 6.1.10).35
9.1.11 In-band Intermodulation.36
9.2 Transmitter.37
9.2.1 Channel Bit Rate.37
9.2.2 Manufacturer's declared output power.37
9.2.3 RF power rise time.37
9.2.4 RF power release time .38
9.2.5 Spurious emissions.38
9.2.6 Adjacent channel power.39
9.2.6.1 Method of measurement for the first adjacent channel .39
9.2.6.2 Method of measurement for the second adjacent channel.40
9.2.6.3 Method of measurement for the fourth adjacent channel .41
9.2.6.4 Alternative Measurement Procedure for Adjacent Channel Power (ACP) .41
9.2.7 Wideband noise.42
9.2.8 Frequency Error.43
9.2.8.1 Definition.43
9.2.8.2 Method of measurement.43
9.2.8.3 Limits.43
9.2.9 Load VSWR capability (clause 6.2.11) .43
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5 ETSI EN 301 842-1 V1.1.1 (2002-01)
9.3 Physical layer, system parameters.44
9.3.1 Receiver to Transmitter turn-around time.44
9.3.2 Transmitter to Receiver turn-around time.45
9.3.3 Tuning Time.45
Annex A (informative): Bibliography.46
History .47

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6 ETSI EN 301 842-1 V1.1.1 (2002-01)
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://webapp.etsi.org/IPR/home.asp).
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 (Telecommunications series) has been produced by ETSI Technical Committee
Electromagnetic compatibility and Radio spectrum Matters (ERM).
The present document is part 1 of a multi-part deliverable covering the VHF air-ground Data Link (VDL) Mode 4 radio
equipment; Technical characteristics and methods of measurement for ground-based equipment, as identified below:
Part 1: "General description and physical layer";
Part 2: "Data link layer".
National transposition dates
Date of adoption of this EN: 4 January 2002
Date of latest announcement of this EN (doa): 30 April 2002
Date of latest publication of new National Standard
or endorsement of this EN (dop/e): 31 October 2002
Date of withdrawal of any conflicting National Standard (dow): 31 October 2002

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
(118,000 MHz to 136,975 MHz), using Gaussian-filtered Frequency Shift Keying (GFSK) Modulation with 25 kHz
channel spacing. Optionally the transmitters, transceivers and receivers may tune between 113,000 MHz to
117,975 MHz.
The present document may be used to produce tests for the assessment of the performance of the equipment. The
performance of the equipment submitted for type testing should be representative of the performance of the
corresponding production model.
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7 ETSI EN 301 842-1 V1.1.1 (2002-01)
The present document has been written on the assumption that:
• the type test measurements will be performed only once, in an accredited test laboratory and the measurements
accepted by the various authorities in order to grant type approval;
• if equipment available on the market is required to be checked it may be tested in accordance with the methods
of measurement specified in the present document or a documented alternative approved by the certifying
authority;
• equipment comply with EN 301 489-22 [5].
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8 ETSI EN 301 842-1 V1.1.1 (2002-01)
1 Scope
The present document states the minimum performance requirements for radio transmitters receivers and transceivers
for ground VHF Datalink mode 4 (VDL mode 4) equipment intended to be used for air-ground data communications,
operating in the VHF band (118,000 MHz to 137,000 MHz and optionally 113,000 MHz to 117,975 MHz) allocated to
the aeronautical mobile service. It is designed to ensure that equipment certified to it will be compatible with the
relevant ICAO VHF Digital Link (VDL) mode 4 Standards and Recommended Practices (SARPs) [1].
Manufacturers should note that in the future, all or part of the frequency band 108,000 MHz to 117,975 MHz may
become available for aeronautical communications.
The present document applies to Gaussian-filtered Frequency Shift Keying (GFSK) systems, with channel separations
of 25 kHz intended for air-ground digital communications. The scope of the present document is limited to ground
stations.
The VDL mode 4 system provides data communication exchanges between aircraft and ground systems supporting
surveillance applications. The supported modes of communication for VDL mode 4 include:
• broadcast and point-to-point communication,
• air-air and ground-air,
• operation without ground infrastructure.
VDL Mode 4 is designed to be an Air/Ground subsystem of the Aeronautical Telecommunication Network (ATN)
using the AM(R)S band and it is organized according to the Open Systems Interconnection (OSI) model (defined by
ISO). It provides reliable subnetwork services to the ATN system.
The present document specifies functional specifications of radio transmitters, receivers and transceivers at
ground-based VHF communication equipment intended to be used for air-ground data communications. The present
document is derived from the specifications:
• Mode 4 standards produced under the auspices of the International Civil Aviation Organization (ICAO) [1].
• Other relevant standards as defined in clause 2.
The present document includes:
• Clause 2 provides references to relevant documents.
• Clause 3 provides general definitions, abbreviations and symbols used.
• Clause 4 provides a general description and architecture of VDL Mode 4 including reference to the OSI model,
communication services, ADS-B and operational scenarios.
• Clause 5 provides functional specifications applicable to the physical layer including transmitter/receiver
requirements and the modulation scheme.
• Clause 6 provides general equipment requirements.
• Clause 7 provides general design requirements.
• Clause 8 covers general test conditions, environmental tests and calibration.
• Clause 9 provides detailed test procedures for the physical layer.
The full physical layer tests are provided which correspond closely to the standard set of tests used for other VDL
systems.
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9 ETSI EN 301 842-1 V1.1.1 (2002-01)
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.) indicate 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
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 and/or edition number or version number) or
non-specific.
• For a specific reference, subsequent revisions do not apply.
• For a non-specific reference, the latest version applies.
[1] Annex 10 to the Convention on International Civil Aviation Aeronautical Telecommunications,
International Civil Aviation Organization.
[2] ISO/IEC 7498-1 (1994): "Information technology - Open Systems Interconnection - Basic
Reference Model: The Basic Model".
[3] ISO/IEC 10731 (1994): "Information technology - Open Systems Interconnection - Basic
Reference Model - Conventions for the definition of OSI services".
[4] ETSI EN 300 113-1: "ElectroMagnetic Compatibility and Radio Spectrum Matters (ERM); Land
mobile service; Radio equipment intended for the transmission of data (and speech) and having an
antenna connector; Part 1: Technical characteristics and methods of measurement".
[5] ETSI EN 301 489-22: "Electromagnetic compatibility and Radio spectrum Matters (ERM);
ElectroMagnetic Compatibility (EMC) standard for radio equipment and services;
Part 22: Specific conditions for ground based VHF aeronautical mobile and fixed radio
equipment".
[6] ISO/IEC 3309: "Information technology - Telecommunications and information exchange between
systems - High-level data link control (HDLC) procedures - Frame structure".
[7] ISO/IEC 8208: "Information technology - Data communications - X.25 Packet Layer Protocol for
Data Terminal Equipment".
[8] ITU-T Recommendation X.25: "Interface between Data Terminal Equipment (DTE) and Data
Circuit-terminating Equipment (DCE) for terminals operating in the packet mode and connected to
public data networks by dedicated circuit".
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10 ETSI EN 301 842-1 V1.1.1 (2002-01)
3 Definitions and abbreviations
3.1 Definitions
3.1.1 Basic reference model definitions
The present document is based on the concepts developed in the open systems interconnect basic reference model and
makes use of the following terms defined in ISO/IEC 7498-1 [2]:
• layer,
• sublayer,
• entity,
• service,
• service access point,
• service data unit,
• physical layer,
• data link layer.
3.1.2 Service conventions definitions
The present document makes use of the following terms defined in ISO/IEC 10731 [3]:
• service provider,
• service user,
• service primitive,
• request,
• indication,
• confirm.
3.1.3 General definitions
For the purposes of the present document, the following terms and definitions apply:
adjacent channel power: amount of the modulated rf signal power which falls within a given adjacent channel
NOTE: Adjacent channel power includes discrete spurious, signal sidebands, and noise density (including phase
noise) at the transmitter output.
Adjacent Channel Rejection: receiver's ability to demodulate the desired signal and meet the BER requirement in the
presence of an interfering signal in an adjacent channel
NOTE: The ratio (in dB) between the adjacent interfering signal level and the desired signal level necessary to
achieve the specified minimum BER, is the adjacent channel rejection (ACR) ratio.
Aeronautical Mobile Service: mobile service between aeronautical stations and aircraft stations, or between aircraft
stations, in which survival craft stations may participate
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11 ETSI EN 301 842-1 V1.1.1 (2002-01)
Aeronautical Telecommunications Network: internetwork architecture that allows ground, air/ground, and aircraft
data subnetworks to interoperate by adopting common interface services and protocols based on the International
Organization for Standardization Open Systems Interconnection Reference Model
aircraft address: unique combination of 24 bits available for assignment to an aircraft for the purpose of air-ground
communications, navigation and surveillance
NOTE: An aircraft may choose not to use this unique address and can use instead a non-unique address.
Automatic Dependent Surveillance-Broadcast (ADS-B): surveillance application transmitting parameters, such as
position, track and ground speed, via a broadcast mode data link for use by any air and/or ground users requiring it
NOTE: ADS-B is a surveillance service based on aircraft self-determination of position/velocity/time and
automatic, periodic or random, broadcast of this information along with auxiliary data such as aircraft
identity (ID), communications control parameters, etc. ADS-B is intended to support multiple high-level
applications and associated services such as cockpit display of traffic information, traffic alert and
collision avoidance functionality, enhanced traffic management in the air and on the ground, search and
rescue support and others.
autotune function: function, performed by the Link Management Entity, that allows a ground VDL Mode 4 station to
command an aircraft to change the operating characteristics of synchronization burst transmissions
Bit Error Rate (BER): expressed as the ratio between the number of erroneous bits received and the total number of
bits received
burst: a VHF digital link (VDL) specific services burst is composed of a sequence of source address, burst ID,
information, slot reservation, and frame check sequence (FCS) fields, bracketed by opening and closing flag sequences
NOTE: The start of a burst may occur only at quantized time intervals and this constraint allows the propagation
delay between the transmission and reception to be derived.
burst length: number of slots across which the VDL Mode 4 burst is transmitted
Co-Channel Interference (CCI): co-channel interference protection defines the capability of a receiver to demodulate
the desired signal and achieve the minimum specified BER performance in the presence of an unwanted signal at the
same assigned frequency
NOTE: The ratio (in dB) between the wanted signal level and the unwanted signal level is the co-channel
interference ratio. The co-channel interference ratio has a major impact on frequency re-use planning
criteria.
conducted measurements: measurements which are made using a direct rf connection to the equipment under test
current slot: slot in which a received transmission begins
Data Link Entity: protocol state machine capable of setting up and managing a single data link connection
Data Link Service (DLS) sublayer: sublayer that resides above the VDL Mode 4 Specific Services (VSS) and the
MAC sublayers
NOTE: The data link service (DLS) manages the transmit queue, creates and destroys data link entities (DLEs)
for connection-oriented communications, provides facilities for the link management entity (LME) to
manage the DLS, and provides facilities for connection-less communications.
data rate: Mode 4 nominal data rate is 19 200 bits/s
delayed burst: VDL Mode 4 burst that begins sufficiently after the beginning of a slot so that the transmitting VDL
Mode 4 station is confident that no other VDL Mode 4 station that it could receive from and is within the guard range is
transmitting in the slot
NOTE: The delayed VDL Mode 4 burst terminates by the end of the slot in which it began (its length is shortened
to ensure completion by the nominal time).
DLS system: VDL system that implements the DLS and subnetwork protocols to carry Aeronautical
Telecommunications Network (ATN) or other packets
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12 ETSI EN 301 842-1 V1.1.1 (2002-01)
frame: link layer frame is composed of a sequence of address, control, information and FCS fields, bracketed by
opening and closing flag sequences
NOTE: A valid frame is at least 11 octets in length and contains an address field (8 octets), a link control field
(1 octet) and a frame check sequence (2 octets). A frame may or may not include a variable-length
information field.
Global Signalling Channel (GSC): channel available on a world wide basis which provides for communication control
ground base station: aeronautical station equipment, in the aeronautical mobile service, for use with an external
antenna and intended for use at a fixed location
ground station coordination: coordination of transmissions from two or more ground stations uses the UTC-minute
time frame
hand held: radio equipment with integral batteries, designed to be hand portable and operated hand held
NOTE: Provisions may be made for external connections and temporary installation into vehicles.
integral antenna equipment: radio communications equipment with an antenna integrated into the equipment without
the use of an external connector and considered to be part of the equipment
NOTE: An integral antenna may be internal or external to the equipment. In equipment of this type, a 50 Ω rf
connection point shall be provided for test purposes.
link: connects a mobile DLE and a ground DLE and is uniquely specified by the combination of mobile DLS address
and the ground DLS address
NOTE: A different subnetwork entity resides above every link endpoint.
link establishment: process by which an aircraft and a ground LME discover each other, determine to communicate
with each other, decide upon the communication parameters, create a link and initialize its state before beginning
communications
link handoff: process by which peer LMEs, already in communication with each other, create a link between an aircraft
and a new ground station before disconnecting the old link between the aircraft and the current ground station
link layer: layer that lies immediately above the physical layer in the Open Systems Interconnection protocol model
NOTE: The link layer provides for the reliable transfer of information across the physical media. It is subdivided
into the data link sublayer and the media access control sublayer.
Link Management Entity (LME): protocol state machine capable of acquiring, establishing, and maintaining a
connection to a single peer system
NOTE: An LME establishes data link and subnetwork connections, "hands-off" those connections, and manages
the media access control sublayer and physical layer. An aircraft LME tracks how well it can
communicate with the ground stations of a single ground system. An aircraft VDL management entity
(VME) instantiates an LME for each ground station that it monitors. Similarly, the ground VME
instantiates an LME for each aircraft that it monitors. An LME is deleted when communication with the
peer system is no longer viable.
Media Access Control: sublayer that acquires the data path and controls the movement of bits over the data path
mobile: radio equipment designed for installation into vehicles
non-integral antenna equipment: radio communications equipment with a connector intended for connection to an
antenna
physical layer: lowest level layer in the Open Systems Interconnection protocol model
NOTE: The physical layer is concerned with only the transmission of binary information over the physical
medium (e.g. VHF radio).
primary time source: normal operation timing mode in which a VDL Mode 4 station maintains time synchronization
to Universal Coordinated Time (UTC) second to within a two-sigma value of 400 ns
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13 ETSI EN 301 842-1 V1.1.1 (2002-01)
private parameters: parameters that are contained in exchange identity (XID) frames and that are unique to the VHF
digital link environment
radiated measurements: measurements which involve the measurement of a radiated field
reference signal level: signal level used in the receiver performance specifications except otherwise stated
reference bit sequence: sequence of bits used in the transmitter performance specifications
secondary time source: timing source used in a failure mode, which applies when the primary time source fails, in
which a VDL Mode 4 station maintains time synchronization to UTC second to within a two-sigma value of 15 µs
Self-organizing Time Division Multiple Access (STDMA): multiple access scheme based on time-shared use of a
radio frequency (rf) channel employing: (1) discrete contiguous time slots as the fundamental shared resource; and (2) a
set of operating protocols that allows users to mediate access to these time slots without reliance on a master control
station
slot: In VDL Mode 4, time is divided into a series of time slots of equal period. Each VDL Mode 4 burst transmission
starts at the beginning of a slot.
station: VDL Mode 4 Specific Services (VSS)-capable entity
NOTE: A station may be either a mobile station or a ground station. A station is a physical entity that transmits
and receives bursts over the rf interface (either A/G or air-to-air (A/A)) and comprises, at a minimum: a
physical layer, media access control sublayer, and a unique VSS address. A station which is also a DLS
station has the same address.
subnetwork layer: layer that establishes, manages, and terminates connections across a subnetwork
superframe: group of slots that span a period of one minute
NOTE: The start of the current superframe is aligned with the start of the slot that is currently being used for
transmission. The next superframe starts one minute after the current slot.
synchronization burst (or "sync" burst): VDL Mode 4 burst which announces, as a minimum, existence and position
NOTE: Ground stations announce existence, position, and the current time. Mobile stations lacking timing
information can then derive the slot structure from ground synchronization bursts. Mobile stations lacking
position information can derive position from both mobile and ground synchronization bursts. This
periodic information is used in various ways including ADS-B, secondary navigation, and simplifying the
LME algorithms.
Time Division Multiple Access (TDMA): multiple access scheme based on time-shared use of an rf channel
employing: (1) discrete contiguous time slots as the fundamental shared resource; and (2) a set of operating protocols
that allows users to interact with a master control station to mediate access to the channel
unicasted transmission: transmission addressed to a single station
VDL Mode 2: VHF data link using a differentially encoded 8 phase shift keying modulation scheme and carrier sense
multiple access
VDL Mode 4: VHF data link using a Gaussian Filtered Frequency Shift Keying modulation scheme and self organizing
time division multiple access
VDL Mode 4 burst: VHF digital link (VDL) Mode 4 burst is composed of a sequence of source address, burst ID,
information, slot reservation, and frame check sequence (FCS) fields, bracketed by opening and closing flag sequences
NOTE: The start of a burst may occur only at quantized time intervals and this constraint allows the propagation
delay between the transmission and reception to be derived.
VDL Mode 4 Specific Services (VSS) sublayer: sublayer that resides above the MAC sublayer and provides VDL
Mode 4 specific access protocols including reserved, random and fixed protocols
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14 ETSI EN 301 842-1 V1.1.1 (2002-01)
VSS user: user of the VDL Mode 4 Specific Services
NOTE: The VSS user could be higher layers in the VDL Mode 4 Technical Manual or an external application
using VDL Mode 4.
VDL Management Entity (VME): VDL-specific entity that provides the quality of service requested by the
ATN-defined subnetwork system management entity
NOTE: A VME uses the LMEs (that it creates and destroys) to acquire the quality of service available from peer
systems.
VDL Mode 4 station: physical entity that transmits and receives VDL Mode 4 bursts over the rf interface (either A/G or
air-t
...