Background
Mircowave Oven Case Study
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Evolutionary Diagrams
Satellite Control System
Requirements and RBTs
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Satellite Control System
1.
Background
COMBIZ is a company that provides its internal and external customers
with a satellite data communications service. COMBIZ's satellite
communications assets are managed by a Ground Control System (GCS). The
GCS is responsible for the health and maintenance of the Satellite
Control System (SCS) as well as for scheduling bulk data communication
time slots for its customers. The SCS is the primary interface for
COMBIZ's satellite bulk data transmission customers who operate
satellite data communication uplink and downlink sites.
The COMBIZ's satellite constellation consists of three satellites, each
with an 8-hour contact window with one of three GCS ground sites. Thus,
there is 24-hour satellite coverage to address all ground control
system operations and customer data communication requirements. The
three satellites and their hardware and software systems represent the
SCS. The three ground control sites represent the Ground Control System.
The GCS directs the SCS activities on the basis of pre-scheduled time
slots. Time slots are allocated for maintenance activities and customer
data transmission preparation, e.g., pointing a satellite by executing
a firing command or updating the SCS's broadcast/location table. Time
slots are also allocated for customer data transmission. After system
initialization, a maintenance time slot is always performed, followed
by a customer data transmission time slot, followed by another
maintenance time slot. Maintenance time slots and customer data
transmission time slots are performed in alternating order. We refer to
the activities performed during a maintenance time slot as a "Manage
Satellites" transaction. We refer to the activities performed during a
customer data transmission time slot as a "Transmit Data" transaction.
2.
Mission
The mission of the Satellite Control System is to manage the system's
satellite assets to ensure the reliable throughput of communication
packets from uplink to downlink satellite data communication sites
within that customer's allotted time slot and to minimize the amount of
time required for allocation to maintenance time slots....
Read more about the Satellite Control System, click here to download the requirement file.
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