User's Manual

SYSTEM DESCRIPTION, INSTALLATION, AND MAINTENANCE MANUAL
ARINC 781-200 SDU and SCM
23-15-30 1-1
DATE TBD
SYSTEM DESCRIPTION
This section includes basic information about the A781-200 system, including the following sections:
• Inmarsat System Overview
• Equipment Overview
• Equipment Specifications
• System Interfaces
• User Interfaces
• Software Description
1. Inmarsat System Overview
This section provides an overview of the Inmarsat satellite communications system and
networks.
Satellite communication systems provide users with long-range voice and data communication
by accessing global satellite and ground communications networks. Satellite communication
systems include global satellite networks, Land Earth Stations (LESs), Ground Earth Stations
(GESs), Aircraft Earth Stations (AESs), and Mobile Earth Stations (MESs).
The LES/GES is the part of the satellite communication system that is on the ground. These
numerous, international stations are responsible for routing voice and data calls from the
MES/AES to their destinations around the world. The MES/AES is the part of the satellite
communication system that is on the aircraft. GES and AES are the terms associated with
Aero-H+ services. LES and MES are terms associated with other satellite communication
services.
Inmarsat is an international organization that operates and maintains multiple geostationary
satellites and satellite networks (I-3 and I-4). For more information about I-3 and I-4 satellite
beam coverage, refer to the Inmarsat website—www.inmarsat.com.
I-3 satellites provide Inmarsat services for aviation (Aero H+ and Swift 64), shipping, and
land-mobile users. The satellites connect to ground telecommunication systems through a
network of GESs. Each I-3 satellite is located over an Ocean Region (OR)—the current OR
names are:
• Atlantic Ocean Region-East (AOR-E)
• Atlantic Ocean Region-West (AOR-W)
• Indian Ocean Region (IOR)
• Pacific Ocean Region (POR)