×

COMMUNICATION SYSTEM FOR ELIMINATING TIME DELAY EFFECTS WHEN USED IN A MULTIPATH TRANSMISSION MEDIUM

  • US 3,689,841 A
  • Filed: 10/23/1970
  • Issued: 09/05/1972
  • Est. Priority Date: 10/23/1970
  • Status: Expired due to Term
First Claim
Patent Images

1. A system for communicating analog and digital information through a dispersive transmission medium, said system comprising:

  • a transmitter including means for generating a carrier signal;

    hybrid modulating means responsive to said analog and digital information for modulating said carrier signal to produce a carrier modulated signal in which said analog and said digital information are transmitted periodically over selected frame intervals of time, said hybrid modulating means comprising;

    means responsive to said analog information for producing periodic sampled amplitudes of said analog information;

    means responsive to said periodic sampled amplitudes for modulating said carrier signal as a function of said periodically sampled amplitudes of said analog information;

    means responsive to said digital information for modulating said carrier signal as a function of said digital information; and

    timing means for controlling said hybrid modulating means so that said carrier modulated signal includes both said analog and said digital information during each said frame interval of time; and

    means for transmitting said carrier modulated signal through said dispersive transmission medium; and

    a receiver including means for receiving said carrier modulated signal as transmitted through said dispersive transmission medium;

    gating means for passing selected portions of said received signal during each said frame interval of time, said gating means being actuated to pass each said selected portions only during a selected time interval within each said frame time interval which is sufficiently removed from the leading portion of each said frame time interval to avoid time delay effects introduced by said dispersive transmission medium;

    detecting means responsive to said selected portions of said received signal during each said frame interval of time for detecting said modulation characteristics thereof during each said frame interval of time;

    time synchronization means responsive to said receiving means for synchronizing the operations of said gating means and said detecting means; and

    means responsive to said detected modulation characteristics during each said frame interval of time for reconstructing said analog information and said digital information.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×