摘要:
An onboard directional plane antenna comprises at least one array of radiating-slot waveguides comprising an alternating succession of three superposed metallic plates and of two dielectric substrates. The two substrates each comprise at least four adjacent waveguides, corresponding and communicating with one another pairwise by way of coupling slots. Each waveguide of the upper substrate furthermore comprises a plurality of radiating slots passing through the upper metallic plate, all the radiating slots of one and the same waveguide being parallel to one another and oriented in one and the same direction, the radiating slots of two adjacent waveguides being disposed in chevrons. Each waveguide of the lower substrate comprises an internal individual feed circuit comprising an individual electronic circuit for phase shifting and amplification.
摘要:
An onboard directional plane antenna comprises at least one array of radiating-slot waveguides comprising an alternating succession of three superposed metallic plates and of two dielectric substrates. The two substrates each comprise at least four adjacent waveguides, corresponding and communicating with one another pairwise by way of coupling slots. Each waveguide of the upper substrate furthermore comprises a plurality of radiating slots passing through the upper metallic plate, all the radiating slots of one and the same waveguide being parallel to one another and oriented in one and the same direction, the radiating slots of two adjacent waveguides being disposed in chevrons. Each waveguide of the lower substrate comprises an internal individual feed circuit comprising an individual electronic circuit for phase shifting and amplification.
摘要:
The invention relates to a multiplexing device comprising a data compressor. The compressed data block leaving said compressor occupies a particular bandwidth.According to the invention, a bandwidth prediction unit calculates said bandwidth and deduces from it the available bandwidth for conveyance in a time space dedicated to Internet traffic.The invention also relates to a multiplexing device and a multiplexing/demultiplexing system.Particular application in a satellite telecommunication system.
摘要:
IP encapsulation equipment comprises encapsulation means responsible for encapsulating into bursts IP packets representing sets of multimedia data delivered by at least one multimedia content server and accompanied beforehand by information data at least partly defining the set of data that is integrated into those IP packets and/or the content of which that set of data forms part, with a view to the broadcasting thereof to receiver equipments via a communication network. It further comprises analysis means responsible for analyzing the information data added to the received IP packets in order to instruct the encapsulation means to encapsulate at least some of those IP packets in selected positions in the bursts as a function of the corresponding information data and so that all the IP packets including the data of a set are encapsulated in a single burst.
摘要:
An optimized method for the transmission of multimedia contents between a multimedia content transmitter and a multimedia content receiver in a mobile radio network transmitting a multimedia content description vector from the transmitter to the receiver, calculating a pertinence score of the content from the description vector and as a function of a user profile associated with a user of the receiver, and recovering, at the explicit request of the receiver, a block or blocks of the content not received by the receiver, with a priority depending on the pertinence score associated with the content to which the missing block(s) belong(s).
摘要:
A method of receiving signals in a spread-spectrum telecommunications system with terrestrial repeaters, and a terminal for receiving, the terminal including two rake receivers (16, 18), each receiver having a set of demodulation channels (20-1, 20-n, 24-1, 24-n) and a combiner (22, 26). A third combiner (28) receives the signals provided by the combiners belonging to the two above-mentioned receivers. In this way, signals arriving from a diffuse system of terrestrial receivers and a complementary source can be received, in spite of the time differences between the different paths of the signals. The terminal can be used in a telecommunications system with numerous multiple paths.
摘要:
The invention concerns a radio communication terminal, comprising first means for transmitting/receiving RF signals to communicate in a cellular radio communication network, said first means being in standby mode when no communication is set up in the cellular network with another terminal or with the network itself. The invention is characterized in that the terminal comprises second means for receiving at least one carrier dedicated to collective data of multimedia contents, said second means being activated only when the first means are n standby mode. The invention also concerns a method for broadcasting and receiving collective data, as well as a system for broadcasting multimedia contents.
摘要:
A method is devoted to synchronizing the transmission of user signals within a single-frequency hybrid network comprising at least one transmission satellite (SAT) and regenerative emitters (E1-E6) tasked with retransmitting received user signals to user terminals (T1, T2), using the same frequency and the same waveform. This method consists of temporally shifting, with respect to a time marker (TM) corresponding to the moment when a chosen element of the user signals arrives at a terrestrial reference arc (RA) from said satellite (SAT), the moment when the user signals received by each emitter (E1-E6) are retransmitted, by a local duration which is a function of the respective positions of the emitter and the satellite (SAT) with respect to a chosen reference position (RP) on said arc (RA), so that the same user signals retransmitted by the satellite (SAT) and the emitter (Ei) reach a user terminal (T1, T2) at roughly the same time.
摘要:
A method is devoted to synchronizing the transmission of user signals within a single-frequency hybrid network comprising at least one transmission satellite (SAT) and regenerative emitters (E1-E6) tasked with retransmitting received user signals to user terminals (T1, T2), using the same frequency and the same waveform. This method consists of temporally shifting, with respect to a time marker (TM) corresponding to the moment when a chosen element of the user signals arrives at a terrestrial reference arc (RA) from said satellite (SAT), the moment when the user signals received by each emitter (E1-E6) are retransmitted, by a local duration which is a function of the respective positions of the emitter and the satellite (SAT) with respect to a chosen reference position (RP) on said arc (RA), so that the same user signals retransmitted by the satellite (SAT) and the emitter (Ei) reach a user terminal (T1, T2) at roughly the same time.
摘要:
In a secure method of deciding on a communication channel in a data decompression device, the compressor detects channels that vary from one frame to another, which are referred to as “active” channels. It transmits active and passive channels in a data block which also contains a state code locating the active data in the starting frame in order to be able to reconstitute it in the decompressor. A reference pattern is transmitted incorporating the passive channels and a majority vote statistical analysis is applied to the states of the passive channels to decide on the state (0 or 1) of each bit constituting the pattern repeated by each passive channel. One particular application of the method is to a satellite telecommunication system.