Abstract: A method for generating cryptographic half-keys makes it possible to generate n pairs (Ki1, Ki2), 1?i?n, of cryptographic half-keys, each of said pairs making it possible to reconstruct an access key KPL specific to a secure apparatus, said method comprising at least the following steps: generating and storing, with the help of a management center distinct from said apparatus, a first series of n half-keys Ki1 on a recording medium; supplying the apparatus with said recording medium so as to generate, with the help of said local key KPL and of the n half-keys Ki1 stored on said medium, a second series of n half-keys Ki2 making it possible to form said n pairs (Ki1, Ki2). The method applies notably to the creation of several keys for access to a secure apparatus.

Abstract: A method for generating cryptographic half-keys makes it possible to generate n pairs (Ki1, Ki2), 1?i?n, of cryptographic half-keys, each of said pairs making it possible to reconstruct an access key KPL specific to a secure apparatus, said method comprising at least the following steps: generating and storing, with the help of a management center distinct from said apparatus, a first series of n half-keys Ki1 on a recording medium; supplying the apparatus with said recording medium so as to generate, with the help of said local key KPL and of the n half-keys Ki1 stored on said medium, a second series of n half-keys Ki2 making it possible to form said n pairs (Ki1, Ki2). The method applies notably to the creation of several keys for access to a secure apparatus.

Abstract: The invention relates to a frequency hopping communication method in which the data travels over time-variable frequency bearers. A frequency bearer is defined as a subset pair of carriers in a channel of a set of frequency channels (RF). The choice of the frequency bearers is derived from a pseudo-random draw.

Abstract: A relay station used in a communication network that has a tree-structured architecture including a number of hierarchical levels, the communication network including a base station of the highest hierarchical level, one or more relay stations and one or more subscriber stations, wherein a relay station has two radio modules, a first radio module being designed to communicate with stations of lower hierarchical level and a second radio module being designed to communicate with stations of higher hierarchical level, the two radio modules being synchronized in their MAC layer and the relay station including at least one antennas connected to the MAC layer of the radio modules.

Abstract: A method and device for implementing a smart antenna in a network that uses a deterministic access protocol, one or more mobile stations MS and at least one base station BS, the transmitted data being included in a data frame, wherein it comprises at least the following steps: On entry into the network: the step of synchronizing a mobile station MS equipped with an FESA directional antenna on a transmission from the base station by changing beam for a duration at least equal to a frame in order to aim the directional beam toward the base station BS to obtain the best signal reception, the step of following the synchronization of the mobile station on the transmission from the base station, and implementing an aiming tracking algorithm in order to retain the best signal reception, the step of determining the parameters for defining the downlink or the uplink by decoding signaling messages contained in the message transmitted by the base station, triggering a network entry procedure.

Abstract: The invention relates to a frequency hopping communication method in which the data travels over time-variable frequency bearers. A frequency bearer is defined as a subset pair of carriers in a channel of a set of frequency channels (RF). The choice of the frequency bearers is derived from a pseudo-random draw.