The purpose of this study is to review the requirements on mobile satellite networks (within a 10 year time frame) before engaging a more detailed study on the required technical developments. This study shall address: (1) a review of the different classes of users and their requirements for satellite based mobile services (2) a review of the constraints associated with the design or the use of satellite networks such as propagation and frequency allocation (3) a review and a comparative analysis of system design options â e.g. nature of orbit, ISL or not, regenerative OBP or not, On Ground Beam Forming, ... â (4) the definition of high level requirements on future satellite networks and their validation through a first-level technical analysis aimed at validating their feasibility within the targeted time frame. The results of this activity will be disseminated so as to engage on a future detailed activity onARTES 1. Participants to this activity could be: MSS operators, MSS network designers, prime satellite and payload manufacturers, user terminals manufacturers, ground infrastructure providers. This study shall take the benefits of previous efforts engaged by ESA,including market studies (M2M), or Benefit analysis of integration of Mobile Satellite Systems in terrestrial mobile networks. Procurement Policy: C(1) = Activity restricted to non-prime contractors (incl. SMEs). For additional information please go to EMITS news "Industrial Policy measures for non-primes, SMEs and R&D entities in ESA programmes".