SSH EN 301 841-2 V1.1.1:2004

Electromagnetic compatibility and Radio spectrum Matters (ERM); VHF air-ground Digital Link (VDL) Mode 2; Technical characteristics and methods of measurement for ground-based equipment; Part 2: Upper layers

Scope

The present document applies to VDL Mode 2 ground-air digital communications using Differential Eight Phase Shift
Keying (D8PSK), intended for channel separations of 25 kHz. The VDL Mode 2 system provides data communication
exchanges between aircraft and ground based systems. The scope of the present document is limited to ground based
stations.
The VDL Mode 2 system is designed to be an Air/Ground sub-system 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 shall provide reliable subnetwork services to the ATN system.
The present document provides functional specifications for ground-based radio transmitters, receivers, and transceivers
intended to be used for ground-air data communications. The present document is derived from the following
documents:
• VDL Mode 2 SARPs version 3.0. ICAO, annex 10 Volume III part I [1];
• Minimum Operational Performance Standards for Airborne Radio Communications Equipment Operating
within the Radio Frequency Range 117,975 MHz to 137,000 MHz [2];
that specify the airborne transmission system.
The present document consists of two parts:
• The first part provides functional specifications and test procedures for physical layer.
• The second part provides functional specifications and test procedures for link and sub-network access layers.