23-11-2012, 01:15 PM
SATELLITE BASED VOICE COMMUNICATION FOR AIR TRAFFIC MANAGEMENT
1SATELLITE BASED VOICE.pptx (Size: 1.48 MB / Downloads: 35)
INTRODUCTION
Interconnecting ground based communication facilities with suitably equipped aircrafts.
IP is considered as the common network layer protocol for communication.
To define IP in ground end, a standard is proposed,
i.e. ED-137A.
Aircrafts are considered as mobile IPv6 clients.
The link gateway (LGW) act as an optimization entity between both ends.
PROPOSED ARCHITECHTURE
The ground end consists of air traffic communication centre (ACC), airline operation centre (AOC), ground earth station (GES), link gateway (LGW)...
The whole traffic route is divided into hexagonal structures called sectors .
Aircrafts occupying various sectors communicate with ground at different frequencies.
Sector floor control allots these sector frequencies to aircrafts.
LINK GATEWAY
A translation and link optimization entity.
Translates between media protocols defined in ground segment and those received from or send to aircraft.
Supports voice compression.
The limited data rate of a satellite communication system requires packet size reduction of data.
For addressing an aircraft within a sector, gateway uses care-off address of aircraft.
SECTOR FLOOR CONTROL
Floor control connects voice application services to link gateways.
These elements allot particular sector frequency for transmission of data from Ground to aircraft or vice versa.
Performs speaker arbitration and provides priority over ride mechanisms
communication services
Session Interface Protocol (SIP) dialog establishment.
The ground system establishes a SIP dialog to sector floor control. Then it reflects a virtual sector. If the controller wants to communicate with more than one aircraft ,it could open more sessions.
Aircraft need to join these virtual sector in order to complete communication. This requires flight crew interaction.
Thus Pilot is informed by a controller about the next information.