Patents Assigned to L'Etat Francais and Telediffusion de France S.A.
  • Patent number: 5191576
    Abstract: A method for the diffusion of digital data designed to be received notably by mobile receivers moving in an urban environment, that is, in the presence of stray signals and jamming, and in conditions of multiple propagation (Rayleigh process) providing an optimized mode of setting up the frame structure of the broadcast signal, so as to derive the maximum benefit from the resistance of the system to pulsed stray signals and to jamming. The header of each frame has a first empty synchronization symbol and eventually a second, unmodulated wobbled signal forming a two-stage analog synchronization system. So, the recovery of synchronization is achieved in an analog way, without prior extraction of a clock signal at the binary level. The constitution of the sequence of the useful symbols in the frame results from temporal and sequential interlacing operations, combined to obtain an implicit de-interlacing at the receiver.
    Type: Grant
    Filed: October 17, 1991
    Date of Patent: March 2, 1993
    Assignee: L'Etat Francais and Telediffusion de France S.A.
    Inventors: Daniel Pommier, Bernard LeFloch