Satellite
The satellite industry is experiencing a phase of significant
change. New applications continue to develop at a rapid rate,
exploiting higher and higher frequencies; applications are no longer
restricted to use of the geostationary orbit, but can exploit low,
medium and intermediate Earth orbits; even the organisations that
dominated the early years of the industry are reinventing
themselves. All of these changes have implications for use of the
spectrum by satellite applications. Today, successful exploitation
of satellite systems demands a thorough understanding of both the
technical and commercial constraints and opportunities that now
exist. Drawing upon our work for organisations such as the European
Space Agency, Eutelsat, Inmarsat, ICO Global Communications and
DACOM Corporation, we help our clients maximise the benefits they
can gain from the introduction and use of satellite systems.
Communications
The satellite communications sector continues to thrive. Existing
applications such as VSATs, for which Aegis worked with ETSI to
develop the Ku-band transmit and receive standard now used across
Europe, are enjoying a new lease of life. New satellite systems will
deliver voice and data to handheld phones, and broadband access via
rooftop terminals. In addition, there are the so-called Little-LEOs
that will provide lower bandwidth data services and messaging. The
arrival of these non-geostationary systems has led to a significant
increase in the complexity of the interference environment
associated with satellite operations – a complexity which the Aegis
Spectrum Engineering Toolkit is well able to handle. Furthermore,
the new dynamic interference environment has meant that a whole set
of new regulatory procedures is required. The issues that have to be
addressed in setting up these new procedures have not yet been fully
resolved; however, we contribute regularly to the ITU-R Study Groups
addressing these issues.
Broadcasting & Multimedia
The availability of spectrum both for key infrastructure
services, such as SNG
and outside broadcasting, and for programme delivery, is fundamental
to the broadcasting industry. We have been closely involved in
ensuring both that such spectrum is made available, and that
broadcasters are able to use bandwidth in an efficient and effective
fashion. Our work in the industry has ranged widely, including:
participation in the design of receiver technology, simulation of
specific sharing issues between broadcast and other applications,
harmonisation of spectrum use across Europe and market analysis of
the commercial viability of new services such as satellite digital
audio broadcast (S-DAB). We have also been closely involved in the
convergence of mobile and broadcast services provided by satellite,
as, for example our examination of Internet provision by satellite
for an Asian client.
Earth Observation & Space Science
Earth observation by satellite (including meteorological
applications) is another growing area, as the potential
environmental, scientific and social benefits come to fruition. This
places two key demands on the radio spectrum. Firstly, in the case
of microwave sensors (both passive and active) large bandwidths are
required in order to achieve the necessary sensing resolution.
Secondly, the frequency allocations commonly used for Earth
observation applications tend to be shared with terrestrial
services. In the case of the space-to-Earth data link any sharing
problems can usually be overcome by selecting an appropriate
frequency and the careful siting of the ground terminal. However, in
the case of the spaceborne sensor there are more complicated issues,
including the scattering of terrestrial transmissions into the
field-of-view of the sensor. We have experience in modelling and
resolving a wide range of problems faced by the Earth observation
community.
Navigation
Satellite systems such as GPS
and GLONASS
have long been used for global navigation and have faced a variety
of spectrum sharing problems. The next generation of Global
Navigation Satellite Systems (GNSS) is expected to operate within a
different institutional framework and will also have to operate
within tight spectrum constraints. Efforts are currently underway to
identify appropriate spectrum allocations and at the same time
address the spectrum-sharing processes that are implicit in such an
excercise. Through our combined work in the avionics and satellite
sectors we are able to help our clients understand the key issues
affecting GNSS.
Satellite Control (TT&C)
Whatever the satellite system, there is always a need for
Telemetry, Command and Ranging (TC&R) links (also referred to as
Telemetry, Tracking and Command, TT&C). These links can either
operate in allocations dedicated to Space Operations or in the
service allocation itself.
For further information on how Aegis can help your organisation
make the most of the opportunities that satellites can offer,
contact us at enquiry@aegis-systems.co.uk.
See also:
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