INMARSATS TRANSFER ORBIT AND PAYLOAD TESTING SUPPORT SERVICE TOPS: EVOLUTION AND RECENT ACHIEVEMENTS

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• INMARSATS TRANSFER ORBIT AND PAYLOAD TESTING
  SUPPORT SERVICE (TOPS) EVOLUTION AND RECENT
  ACHIEVEMENTS
• Emanuele Guariglia
• Senior Manager, Ground Stations Engineering
• Inmarsat Ltd, London, U.K.

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Inmarsat Ltd company background

• Inmarsat was established in 1979 as an
  inter-governmental organization (IGO). Its
  initial remit was to provide safe and reliable
  ship-to-shore and shore-to-ship satellite-based
  communications for ship management, including
  safety and distress applications
• Inmarsat was privatised in 1999 and ownership
  passed on to a number of major worldwide telecom
  operators
• In December 2003 two leading private equity
  groups, Apax Partners and Permira, have acquired
  a majority stake of Inmarsat
• There are now in excess of 290,000 Inmarsat
  terminals worldwide (maritime, land mobile,
  aeronautical). Data traffic accounts for more
  than 50, the rest being voice

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Inmarsat Ltd drilling down to satellite ops
(1)

• Inmarsat currently operates a fleet of 9
  satellites, 4 Inmarsat-2s and 5 Inmarsat-3s.
  Three fourth-generation satellites (Inmarsat-4s)
  are now being manufactured by Astrium (two to be
  flown and one ground spare), with the first
  launch scheduled to take place before the end of
  2004
• Inmarsat owns and operates its own satellite
  control facilities, with 5 prime and 3 back-up
  TTC stations, a Satellite Control Centre (SCC)
  in London and an Operations Back-up Centre (OBC)
  in a different London location, all connected by
  a fully redundant digital data communications
  network
• 3 of the above TTC stations house
  dual-polarisation C-band full-motion antennas
  which are capable of providing transfer orbit
  support

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Inmarsats Satellite Control Network prime TTC
Stations
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Inmarsats Satellite Control Network High Level
Architecture
L. COWICHAN
P. POINT
FUCINO
BURUM
BEIJING
EIK (Bck)
AUCKLAND (Bck)
LMA
LMA
LMA
FMA
LMA
LMA
LMA
FMA
LMA
LMA
LMA
LMA (SAS)
FMA
LMA
LMA
LMA
LMA (SAS)
LMA
NUDOL (Bck)
REDUNDANT DATA COMMUNIC. NETWORK
LMA
PRIME SCC (London City)
BACKUP SCC (North London)
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Inmarsat Ltd drilling down to satellite ops
(2)

• Inmarsat has just completed a major
  augmentation/upgrade to its satellite control
  network, largely driven by the upcoming
  Inmarsat-4 satellites, but also by maintenance
  considerations as some equipment was approaching
  end-of-life
• Technical aspects of this presentation will only
  consider the new (upgraded) network
• This presentation will provide a short
  introduction and history of the TOPS service
  before dwelling on the technical solution with
  its numerous advantages in terms of simplicity
  and flexibility

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Why TOPS at SpaceOps 2004? (1)

• At SpaceOps 2000 in Toulouse, Inmarsat presented
  a paper entitled Cross Network Support
  Inmarsats Experiences
• In that paper, Inmarsat described its approach to
  satellite control and in particular to the
  management of the Launch and Early Orbit Phase
  (LEOP) for its second, and its third generation
  satellites
• Particular emphasis was given to the aspect of
  LEOP TTC ground support, and the paper covered
  Inmarsats early experiences of transfer orbit
  support for external clients, on a commercial
  basis

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Why TOPS at SpaceOps 2004? (2)

• Now, thanks to its recent network upgrade,
  Inmarsat can offer a new approach which provides
  more standardisation (e.g. telemetry, telecommand
  and ranging interfaces to the client control
  centre), but at the same time much more
  flexibility
• This new approach results in increased overall
  efficiency and automation, leading to
  considerable cost savings for the client
• In addition, the increased level of
  interoperability will generate more opportunities
  for cooperation between different organisations,
  allowing cross-network support to become more
  common
• We therefore feel that SpaceOps 2004 provides the
  ideal forum to illustrate this service

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Inmarsats TOPS looking back (1)

• The prime focus of Inmarsats Satellite Control
  Department remains that of controlling Inmarsats
  existing and future satellites (both during
  transfer orbit and on-station)
• However, the philosophy behind its TOPS service
  is to take advantage of existing infrastructure,
  resources and expertise to provide a service to
  external clients
• Inmarsat has been fully responsible for the LEOP
  (including mission management) of its third
  generation satellites. Inmarsat is now getting
  ready to support its fourth generation satellites

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Inmarsats TOPS looking back (2)

• Today, almost four years after the inception of
  the commercial service, Inmarsats TOPS is
  firmly established, with service being offered
  from Inmarsats LEOP TTC earth stations at
  Fucino in Italy, Beijing in China, Lake Cowichan
  on Canadas west coast, and the Satellite Control
  Centre (SCC) in London
• Transfer orbit operations of eleven satellites
  have been successfully supported so far on a
  commercial basis (four during the six-month
  period April September 2003). The launch of the
  first Inmarsat-4 satellite in 2004 is now fast
  approaching

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Inmarsats TOPS the baseline solution

• For its upgraded ground control network, Inmarsat
  has adopted multi-standard CortexNT baseband
  equipment from IN-SNEC, and a TCP/IP based data
  communications network, resulting in the
  provision of a streamlined service with simple
  interfaces, in most cases removing the need for
  the client to send any equipment or personnel to
  the LEOP TTC stations
• Direct telemetry, telecommand, ranging, and
  azimuth/elevation collection interfaces (in
  addition to voice) can be provided at the client
  Mission Control Centre (MCC) through dedicated
  TCP/IP socket connections
• At the MCC end, the adoption of the CortexNT data
  interface is well established in the industry,
  and this in turn reduces to a minimum the level
  of customisation and of compatibility testing
  required

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Connectivity Diagram
Cortex NT
70 MHz TX
TC
IF Mod
A-Link
Leased
RNG Unit
ROUTER
ROUTER
ROUTER
TMRG
IP
ISDN
B-Link
AZ/EL
IFR
TM Unit
Station MCS
ISDN
London
MCC
TTC Station
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Ground Station Configuration
 
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Top-level Configuration of Upgraded Inmarsat LEOP
Network
  Figure 2-3 Top-level Configuration of Upgraded
Inmarsat LEOP Network
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Inmarsat Customer Interfaces
 
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Inmarsats TOPS flexibility (1)

• Based on state-of-the-art DSP technology, the
  CortexNT is a multi-mission system supporting all
  the common TM/TC and Ranging standards for GEO
  satellites applications. The interface with the
  MCC is based on the standard TCP/IP protocol
  provided by IN-SNEC.
• Spacecraft Compatibility Testing as an
  alternative to the traditional use of a suitcase
  simulator at the earth station, a Cortex unit
  can easily be set up in the spacecraft
  integration room, with a data link to the MCC.
  Depending on the interface arrangements,
  frequency converters may be required.

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Inmarsats TOPS flexibility (2)

• Ranging/AZ EL data collection the client can
  have direct socket interfaces to the Cortex
  ranging port and to an MCS monitoring port.
  Alternatively, Inmarsat can carry out this task
  on request, and each time prepare an appropriate
  ASCII file and make it available to the client.
• Provision by the client of orbital elements (for
  generation by Inmarsat FD of Antenna Pointing
  Element Sets, or APES) several formats are
  supported, e.g. true of date, Cartesian and
  Keplerian elements.

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And finally a look at our LEOP antennas at
Fucino, Beijing and Lake Cowichan, and at our SCC
in London!
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Fucino (Italy)Multi-Function Antenna(13 m)
operated by Telespazio
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Beijing (China)Multi-Function Antenna(15
m)operated by CLTC
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Lake Cowichan (British Columbia,
Canada)Full-Motion Antenna(13 m)operated by
Teleglobe
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Satellite Mission Room(SCC, London)
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• THANK YOU!