Thales

Catherine Lamy-Bergot

Cyril Bergeron

Benjamin Gadat

Frédéric Ngo Bui Hung

Sébastien Marcille

Sebastien Herry

Jean-Luc Rogier

Jean-Claude Thill

Sylvain Traverso

Erwann Renan

Roberta Fracchia

Raphael Massin

Jean-Baptiste Chantelouve

Gilles Monzat De Saint Julien

Jean-Yves Bernier

Philippe Crambert

Pierre Hammes

Fracchia Roberta

Gaschi Jean-François

Merel Dominique

Crambert Philippe

Bertrand Marin

Isabelle Herbin

Fabien Verhaeghe

Dominique Merel

Gilbert Multedo

Sébastien Lys

Multedo Gilbert

Fabien Verharghe

Jean-François Gaschi

Rémi Painchault

Didier Chulot

Nathalie Haziza

Jean-Denis Dubant

Jonathan Guyot

Benoît Letellier

Sébastien Charlot

Jean-Francois Gaschi

A method and system is provided for transmitting data in a communication system operating in the HF band comprising a link layer and a physical layer. The system comprises a transmitter and a receiver. The transmitter comprises at least one scheduler. The method comprises a step of segmenting at least two data streams F,Feach of the streams having a service constraint, each being segmented into a plurality of data sub-blocks FBi, a step in which the data sub-blocks are transformed into a frame then a step of coding and interleaving the first frame TF, and of the second frame TF, producing sub-frames STF, STF, then generating a frame to be transmitted by mixing n sub-frames STFof the data stream Fwith m sub-frames STFof the data stream F.

System and method for transmitting a plurality of multi-service streams over an HF band

A method for managing the HF frequencies in a broadband communication network, comprises the following steps: determining the range of passing frequencies for a user for a given link and SLA service; establishing the set of authorized frequencies S&#x2033; in the transmission range of the user with the different power and modulation configurations for each frequency; analyzing the received spectrum in order to determine the frequency or frequencies already used and deciding, on the basis of their associated usage type, whether they must be excluded; for each possible frequency fl of the set S'&#x2033;, determining the necessary power, i=1 . . . N, j=1 . . . m for each of the m possible rate/waveform configurations, taking into account the power limit on each frequency fl; allocating the frequencies fl of the set S&#x2032;&#x2033; to the different users, their modulation and their power, by taking account of multi-carrier constraints.

Method for managing HF frequencies in broadband use

A system and method for communication resource allocation, a resource including a time slot and at least one associated channel, said channel including at least one transmit and/or receive frequency usable during said time slot, in a mobile meshed network including a first set of radio transceivers communicating with one another via radio links, at least one group, comprising a second set of at least one radio transceiver of said first set, said second set including a master transceiver in a master/subordinate relationship with all the radio transceivers of the second set, a central radio transceiver of the network belonging to said first set. Said system is characterized in that it comprises first means for determining said group(s), second means for allocating all or some of said resources through assignment of a resource to a single group which is able to use said resource for one or more communications between radio transceivers of said group; or through allocation of a resource to a single first group which is able to use said resource for communication between radio transceivers of said first group and radio transceivers belonging to one or more neighboring destination groups, if none of the other resources sharing the same time slot with said resource is determined as belonging to one of said destination groups or to a different second group for links to one of said destination groups of the first group, except if the first group and the second group have no transceiver having a common radio neighbor in the destination groups. Finally, said system comprises third means for allocating, for all or some of the groups, all or some of the resources allocated to said group, to one of the radio transceivers in the group.

System and method for communication resource allocation

A method for improving the HF band link establishment in a communication system including one or more transmit terminals and one or more receive terminals, at least one of the terminals having a broadband capability, comprises the following steps: creating call bands and listening bands according to the broadband transmit and/or receive capabilities, the minimum number of bands being suitable for covering the entire frequency plan; minimizing the number of bands and then maximizing the number of frequencies in each of these bands of size B; distributing the bands Bin time by arranging the bands in descending cardinal-value order, and allocating a frequency fto each band B; transmitting/receiving in broadband mode, by checking that the selected transmit frequencies are not already in use.

Method for improving the HF band link establishment using a broadband capability

A system for establishing and sustaining a broadband communication is provided wherein: the first master post is suitable for transmitting a known test sequence on a sub-band Bk to the second called post as soon as the said second called post acknowledges the receipt of a communication setup message on a frequency fi; the said second controller being suitable for determining quality scores on the Mk frequencies of the sub-band Bk and for transmitting the said values of quality to the first master post. The first master post is suitable for determining and for evaluating the capability of the sub-band Bk to respond to the SLA target service a sub-channel on the basis of the scores of qualities received, and for selecting the sub-band Bk which exhibits the required capability and thereafter for triggering the communication with the said second post. Application to HF broadband systems.

Method and system for the establishment and sustaining of a broad-band link

A method and system of communication in a wide band high frequency HF communication system is disclosed. The system includes at least n communication channels, an interleaver common to the n communication channels, a means for determining the quality of communication of each of the n communication channels. At least the following information is introduced into the structure of the frame of the data at the level of an autobaud: an item of information about the modulation employed on each of the n communication channels ch, an item of information about the interlever common to the n communication channels, the corrector code FEC employed, the number of communication channels employed (n) as well as for each one its identifier id. The modulation is chosen on channel n, a common coding and interleaving are operated on the n channels, and the information introduced in the shared autobaud is transmitted.

Method and system of communication using dynamic modulation and coding schemes on wide band HF communication channels

A method and system is provided for dynamic allocation of power required on a number n with n greater than 1 of an HF communication system, comprising an amplifier of maximum total power and at least one step in which the power and/or the modulation is managed on all the n pathways of said system so as to optimize a given probability of error termed the operating point for a maximum bitrate under the constraint of the total power imposed by the operation of said system.

Method and system allowing the dynamic allocation of power and/or of modulation in a system comprising N channels

A method and system are provided for reducing the peak factor in a multi-carrier communication system, the data being transmitted on m channels comprising, in the transmission of data in the form of a frame, a step in which a number d of desynchronization symbols are introduced at the start of each of the frames, the number d being chosen as a function of the transmission channel number concerned.

Method and system for desynchronizing channels in multi-carrier communication systems

A method of determining the coding parameters of a variable-resolution video stream by a video coder, said video stream including multiple resolution layers and being compressed so as to be transmitted at a given rate or a given quality through a heterogeneous network to multiple users, said method including a classification step to associate each resolution level with a group of users and to determine the optimal coding parameters for each resolution level as a function of the requirements of each group of users.

Method and system for determining coding parameters on variable-resolution streams

A method for adaptive communication in an HF frequency band includes at least one of the following steps: the determination of a payload subband S that is available for a transmission in the HF band, the selection in the payload subband S of a set of n frequency channels of identical width according to a frequency allocation plan and the quality of the link of each of said channels, or the simultaneous transmission on the n frequency channels of a signal complying with an HF waveform.

Method and system of adaptive communication in the HF band

A method for optimizing a video transmission, in a constrained environment using a video coder adapted for coding the video data to be transmitted, includes determining one or more compression parameters for the video coder considered to transmit the video data at a given throughput or for a given quality. The method defines and uses reference charts for the coder considered, and predicts for the part of the video sequence undergoing compression, using the reference charts, compression parameters to be used, such as the quantization interval, by selecting a chart for which the targeted range of throughput or of quality is the closest in distance to the part of the sequence to be compressed, while complying with a given margin, and updates with an iterative method the prediction step to converge on the best choice of parameterization. The iteration includes at least one compression step followed by a verification step, to compress the video data to be transmitted with the parameters.

System and method for determining encoding parameters

A method for protecting multimedia data encoded by the H.264 standard, the data being encapsulated in a structure of the network abstraction layer or NAL type, characterized in that the user inserts at least one redundancy NAL containing the error-correcting code used for transmitting the data.

Method for protecting multimedia data using additional network abstraction layers (NAL)

Method for transmitting data in a transmission system, the data being transmitted in the form of packets including a compressed header field and a data field and according to a format suited to the transmission system comprising the following steps: recovering the data packet to be transmitted including a compressed header and useful data, identifying the header part from the useful-data part, applying a corrector coding which is selected at the level of the header, and providing the resulting new packet to the link layer, while also communicating the protection mode used, generating the link header according to the transmission format of the relevant transmission system integrating the mode of protection used, and the adaptation of the CRC checksum of the link layer, on reception, performing the error corrector decoding in two steps.

Method and device for the reliable transmission of compressed network headers

Method of estimating the perceived quality of a video sequence at a maximum spatial resolution and a maximum temporal resolution, and at a lower spatial resolution and/or temporal resolution, said method including filtering said video sequence at the lower temporal resolution and/or the lower spatial resolution so as to produce a filtered video sequence at the maximum spatial and temporal resolutions; determining a reference sequence that is, at most, equal to the content of said video sequence at the maximum spatial and temporal resolutions; and calculating a metric of perceived quality of said video sequence at the lower temporal resolution and/or the lower spatial resolution.

Method of estimating video quality at any resolution

A method for transmitting multimedia data in an ad hoc network including receiving a packet on a radio interface, and if the node is not its destination, is copied into a local buffer Q while awaiting the verification of the packet, the packet is also uploaded to the top layers for on the one hand verification of its possible corruption and on the other hand optional storage in a local stack P of long duration with additional information about the data fragment. In the case where the transmission on the last hop before the current node has corrupted the packet, it is verified that the headers are intact so as to be able to route the packet appropriately, after having verified whether the stack P is present and whether it contains an intact version of the packet, in which case it is the intact payload which will be substituted for the erroneous payload in the buffer Q. If the stack P is not present or does not contain the packet, then the method will nevertheless propagate the packet when only the payload has been corrupted since a robust multimedia decoder might be able to use this packet correctly.

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Gennevilliers, France

Catherine Lamy-Bergot