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The 26 years old TT&C Ground Network of CNES needs some refurbishments and extensions. A project called « Cormoran » was recently decided to replace the eldest TT&C stations, to expand services to data reception (in X-band) and to increase interoperability and automation. Beyond the usual technical and performance challenges which are derived from the satellite mission requirements, high level objectives of enhanced capacity and reduced costs were assigned to this project by the CNES Management. In fact, the workload of the GN is expected to be multiplied by 3 to 4, in the next 5 years. This increase is considered beyond what can be covered at a reasonable cost with the support of an external GN (e.g.: commercial GN). Therefore, it is a real challenge for the project to propose innovative and efficient solutions to cope with the extra load and to maintain the running costs under their current level. This paper will first introduce the context of the CNES GN and the rationale for its evolutions. It will then describe the components of the "CORMORAN" project and will detail how each of them will contribute to the high level objectives: the features of the new systems will be presented, among which the automation of the network operations center, the modernized stations and their automated maintenance and the original data distribution system intended to reduce the bandwidth requirements on communication lines. Finally, the paper will conclude with a summary of the awaited outcomes of the ongoing developments, in quantified terms of increased GN capacity and stable running costs. -IntroductionThe French Space Agency, CNES, has been operating an S-band Ground Stations Network (GSN) for more than 26 years. This is a multi-mission asset that provides Tracking, Telemetry and Command (TT&C) services to all CNES satellite missions (currently 17 in flight satellites) in Launch and Early Orbit Phase (LEOP), in mission phase and in the End Of Life operations (EOL). On occasions, the spare capacity of the network may be used to provide same services to satellites of other space agencies in the frame of cross supports or to launchers, on a non interference basis. Also, supports to satellite of other organizations are possible, always for short duration operations and under special conditions: the main rule here is that CNES will not compete with commercial providers of same services in open calls for tender; the exceptions to the rules are when the risks for a first mission must preferably be assumed by an Agency, when the support is requested to CNES under an inter-government umbrella or when the CNES assets are the only ones capable of providing the required services (e.g.: technical features or geographical location of the antennas).In this context, the main challenges for CNES are to guarantee the availability of the required services to all users and to provide high quality services at a reasonable cost. This must be true whether the users are CNES missions or external missions. It must also remain true along the evoluti...

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Conventionally, when a station network operator needs to extend the coverage of his network he builds a new station. And in that case the coverage extension corresponds to the coverage provided by the new station. Depending on the network mission profile, this coverage increase could be sufficient or not. In the field of TT&C or payload data reception activities for LEO satellites, the benefit of the additional new station may be limited in terms of contact opportunities, depending on the choice of the new antenna location.In the beginning of the 21st century CNES identified new needs regarding the coverage of the polar region for X band data reception capability and of capability of satellite control in S band. These needs were related to future earth observation missions. On the one hand, the workload analysis performed at that time showed that the use of one polar station was not sufficient because of the conflict between the missions. And on the other hand the station work load was not sufficient to justify building a second antenna.At the same time, SSC was looking to establish a second polar station to complement the Esrange Space Center in Kiruna, Sweden and thereby optimize the ground station coverage of every orbit of sun synchronous (SSO) LEO satellite missions, as well as increasing redundancy and capacity. In addition, by adding a second polar station in a different geographical location SSC would be able to reduce the risk of RF interference, which is increasing in the northern artic region. SSC and CNES were able to identify the location of Inuvik, Canada as an optimal location for a second polar station to complement the Esrange Space Center in Kiruna, Sweden, at the same latitude and with almost 180° separation in longitude.The founding of the Inuvik Satellite Station Facility (ISSF) at Inuvik, Canada in 2010 became a unique private-public undertaking between SSC and two space agencies (CNES and DLR) to establish a satellite station capable to provide strategic TT&C and data reception capabilities from a CNES-SSC antenna and a DLR antenna, to a variety of satellite missions, with coordination and backup support between the three parties. As the other part of the station sharing agreement, SSC and CNES also established an additional antenna system at the Esrange Space Center in Kiruna, Sweden, and CNES and SSC set up a scheme for sharing the load and operations of both the Inuvik and Kiruna antennas. This multi-site, public-private partnership between CNES and SSC has evolved since the last presentation at the 2012 SpaceOps, and the evolution of its unique capabilities and features is the subject of this paper.The two sites are operated together, as one site (often referred to as « Kinuvik »), with the load shared seamlessly. This combination forms a unique asset that can command and download significant payload data volumes on every orbit. The ideal geometry and separation between Kiruna and Inuvik gives the optimal solution to download more data by avoiding overlapping coverage. This solution all...