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12.2
Satellite System Economic Principles
The successful implementation and operation of a system or network depend as
much on economics as on technology. Once the development risks have been
identified and addressed properly, the economics of satellite communication can
be defined using the basic principles of capital budgeting and service development.
Geostationary satellite systems are evaluated like other industrial fields, including
394
Satellite Systems Engineering and Economics
public telecommunications services. DTH and VSAT networks employing bent-
pipe repeater satellites are well understood, so it is possible to make accurate
predictions of what it will cost to implement and operate a system.
Unknown factors in system economics often have to do with new technology
that must be developed and introduced for commercial service. Another set of
unknowns involves the expected amount of traffic the system can carry and the
prices users are willing to pay. Furthermore, competition, such as exists in the
United States, is an extremely strong factor that can render even the best system
implementation concept uneconomic.
A satellite system in its entirety is costly to implement, but the technology
provides versatility and flexibility that are potentially greater than that of any other
telecommunications technology. The cost of space segment implementation ranges
from approximately $250 million for one conventional bent-pipe satellite to more
than $10 billion for a complete DTH system. A medium-power GEO communica-
tions satellite delivers any combination of voice, data, and video services between
a potentially large set of Earth stations located within the footprint. A comparable
terrestrial network must be implemented on a wide-scale basis, and rapid relocation
is virtually impossible. A non-GEO constellation, on the other hand, promotes
the concept of ubiquitous global telecommunications service, independent of the
terrestrial infrastructure. For some payload designs, communications satellites are
attractive from an economic standpoint because the particular mix of services can
be altered rapidly and the value of the investment is not lost due to changing
demand. A satellite that has been launched will normally see its use increase over
time even to the end of orbital life, when it must be retired from service.
The communications Earth stations employed to deliver services cover a wide
range of applications and costs. Large Earth stations used as broadcast centers and
telecommunications gateways have long economic lives, since it is possible to
expand, modify, or even replace the specific equipment used to provide new capabil-
ities. Low-cost end-user terminals, particularly DTH receivers, VSATs, and MSS
mobile phones might have relatively short lives of 2 to 5 years. Part of the reason
for that short economic life is the trend toward obsolescence as newer products
are introduced. The advent of microelectronics has greatly increased the versatility
of ground equipment at the same time that unit costs have decreased. Also, higher
power satellites permit a significant reduction in ground antenna size and RF
electronics costs. Those mitigating factors encourage the replacement of functional
but obsolete Earth station equipment.
The approach that follows is meant as a framework for understanding the
underlying economics of a satellite system. It should be possible to use this frame-
work to create a specific economic model of any system so the detailed costs can
be determined. As a rule, the economics of the system go hand in hand with the
functions it is required to perform. Typical studies of system economics consider
the recovery of the original investment by including the time value of money and
computing equivalent annual payments. The investment costs are embodied in the
block diagrams of the elements and for the system as a whole. The annual costs
usually are more difficult to assess, involving labor and other expenses for manag-
ing, marketing, and operating the system, and financial matters such as the cost
of money and taxes. In large, complex networks, costs and therefore revenues must
12.3
System Development Methodology
395
be split among the space segment operator, the Earth station operator, and the
ultimate service provider or distributor. That can be exceedingly difficult to assess
in advance of actually creating the required business structure. Economic studies
are still useful to size the business and to attempt to convince investors (internal
or external) that a satellite system is an attractive investment.
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