Abstract:
A data transmission system in a communication network comprising a data modulator comprises: a first part at the level of the collection point part comprising: an NCR module taking account of an external absolute time reference to reconstitute a network clock, a transmitter module receiving the value of a time reference to be inserted into the data packet to be transmitted and transmitting to the NCR module an information item on an instant of synchronization for the receiver, a second part at the level of the radiofrequency part of a gateway comprising; a receiver module, a module for reconstructing a clock locally, a module for inserting a time reference into a data packet received by the receiver before transmission of the data via the satellite, the first part and the second part exchange encapsulated data.
Abstract:
A method, and associated equipment, for dynamically allocating resources in a satellite network comprising at least one satellite configured to form a plurality of satellite beams and terminals, comprises the steps of: clustering the beams into groups of beams, allocating frequency resources to each of the groups of beams, determining geographical zones in which these frequency resources can be used simultaneously, determining a hop frame comprising first timeslots, in which the frequency resources are allocated to the whole set of terminals of one of the beams of the group, and second timeslots, in which the frequency resources are allocated to a subset of terminals of at least one beam of the group, identifying the subset of terminals and allocating to the terminals of the frequency resources, and uploading of information relating to the overall loading of each of the beams.
Abstract:
A soft handover method with gateway site diversity between a first nominal gateway to a relay satellite of a space telecommunication system and a second redundant gateway to the same satellite comprises a soft handover preparation phase, and a soft handover execution phase that are executed in succession. During the execution phase, a first switchover of the traffic at the ground segment level to the second redundant gateway, and a second switchover at the level of the segment on board the satellite between a first nominal access link of the first nominal gateway and a second redundant access link of the second redundant gateway are finely synchronized.
Abstract:
A multibeam telecommunication satellite comprises a reconfigurable payload, at least one anchor spot access and a plurality of user spot accesses wherein, for a given mobile terminal, the anchor spot access is associated with a unique frequency channel and the user spot accesses are each associated with a frequency channel, and wherein the payload comprises at least one routing module configured to dynamically route the user spot access to the anchor spot access associated with the anchor station and vice versa depending on the position of the mobile terminal, and a transposition module configured to transpose the frequency of the RF signals that originate from the user spot accesses to the frequency associated with the frequency channel of the anchor spot access and vice versa, the transposition of the signals always being to the same frequency for a given mobile terminal.
Abstract:
A broadband multi-beam satellite radiocommunication system configured to implement a scheme for re-use of frequencies from a total band allocated to an uplink comprises a satellite with a multi-beam receive antenna that forms adjacent reception spots of a terrestrial coverage. Each reception spot consists of a central inner zone and a peripheral zone. Each central inner zone is a cellular pattern identical except for a scale factor to geographical cells wherein the principal frequency sub-bands of a bundle of separate or adjacent principal sub-bands are unitarily distributed and the combination of which is equal to a principal band, included in the total band.