countries where they are located. Satellite control and coordination of communication services are
effected through the INTELSAT headquarters located in Washington DC, United States. Detailed
information on INTELSAT operational management, coordination and control, and line-up
procedures is given in the satellite system operations guide (SSOG). Figure 6.8.1 illustrates the management organization for the INTELSAT system. The INTELSAT operations centre (IOC),
located within INTELSAT headquarters, is manned 24 hours a day and is responsible for the
continuous control of the space segment.
6.8.2 Management of domestic satellite communications network operations
The management of domestic satellite communication networks is relatively less complex in
comparison to management of an international network due to a smaller service area, and since the
network including earth stations is generally owned and operated by one or a few entities within the
country, it is possible to centralize operation, monitoring and control functions. An earth station
associated with a network operations and control centre could be co-located with a TTCM earth
station for spacecraft operations or with one of the main traffic earth stations. Proper coordination
between the agency responsible for spacecraft operations, earth station operators and customers like
common carriers and broadcasting agencies is essential for efficient working of the system. Network
management structure in different countries may vary considerably depending on the organizational
set up of the agencies, which may be totally government owned with a single telecommunication
administration or, at the other extreme, may involve several private agencies. In any case, an
operational group responsible for implementation of operational plans, coordination and control is
required to be set up and the responsibilities of individual representatives from concerned agencies
identified.
Initial earth station check-out procedures, line-up procedures, operational procedures, inter-agency
interfaces and procedures for periodic review of operations, reports and coordination meetings have
to be laid down. Monthly, weekly and daily schedules of operations generated by customer agencies
and ratified by the spacecraft manager from the viewpoint of spacecraft operational constraints
should be the primary mechanism for inter-agency coordination. An operations directory should
provide full information for inter-agency communication/correspondence. Log books should be maintained for all subsystems of space segment and ground segment on a shift by shift basis for
keeping track of operational status.
Transmissions from all communication transponders are commonly monitored and network
discipline is maintained by a network operation and control centre (NOCC). Functions and
monitoring facilities of a typical NOCC are described in section 6.8.2.1. Apart from monitoring and
control of carrier transmission, in some networks, particularly those having remote isolated regions
and unattended earth stations, network management may involve the centralized supervision, fault
monitoring and control of remote stations.