Slip corrector means and method for multistation networks

• US 3,350,644 A
• Filed: 05/20/1965
• Issued: 10/31/1967
• Est. Priority Date: 05/20/1965
• Status: Expired due to Term

• Current Assignee: John Mcnair Robert
• Original Assignee: John Mcnair Robert
• Inventors: JOHN MCNAIR ROBERT
• Application Number:
  US04/457,345
• Time in Patent Office: 894 Days
• US Class Current: 375/356
• CPC Class Codes: H04J 13/00 Code division multiplex systems for frequency hopping H04B1/713
• CPC Class Codes: H04J 3/0682 by delay compensation, e.g. by compensation of propagation delay or variations thereof, by ranging
• CPC Class Codes: H04L 7/043 Pseudo-noise [PN] codes variable during transmission synchronisation of spread spectrum receivers H04B1/69

Claims

1. THE METHOD OF MAINTAINING SYNCHRONISM BETWEEN PSEUDO-RANDOM SEQUENCES AT FIRST AND SECOND TRANSMITTERRECEIVER STATIONS OF A WIDE BAND RADIO NETWORK WHICH COMPRISES THE FOLLOWING STEPS:

GENERATING A FIRST PSEUDO-RANDOM SEQUENCE AT THE FIRST STATION;

GENERATING A SECOND PSEUDO-RAMDOM SEQUENCE AT THE SECOND STATION;

DELAYING THE SECOND PSEUDO-RANDOM SEQUENCE TO PROVIDE A PRINCIPAL REFERENCE SEQUENCE, WHICH IS DELAYED BY A PREDETERMINED AMOUNT WITH REFERENCE TO THE SECOND PSEUDO-RANDOM SEQUENCE, AND SEVERAL SELECTABLE SEQUENCES WHICH ARE DELAYED BY INTERMEDIATE AMOUNTS WITH REFERENCE TO THE SECOND PSEUDO-RANDOM SEQUENCE AND TIME-ADVANCED RELATIVE TO THE PRINCIPAL REFERENCE SEQUENCE;

TRANSMITTING SIGNALS MODULATED BY SAID FIRST PSEUDORANDOM SEQUENCE FROM THE FIRST STATION TO THE SECOND STATION;

RECEIVING SAID SIGNALS AT THE SECOND STATION AND DEMODULATING THEM BY ULTILIZING SAID PRINCIPAL REFERENCE SEQUENCE;

SYNCHRONIZING THE PRINCIPAL REFERENCE SEQUENCE WITH THE FIRST PSEUDO-RANDOM SEQUENCE IN SUCH A MANNER THAT THE PRINCIPAL REFERENCE SEQUENCE LAGS IN TIME BEHIND THE FIRST PSEUDO-RANDOM SEQUENCE BY AN AMOUNT WHICH IS DEPENDENT ON THE DISTANCE BETWEEN THE STATIONS;

TRANSMITTING SIGNALS MODULATED BY A SELECTED ONE OF THE TIME-ADVANCED SEQUENCES FROM THE SECOND STATION TO THE FIRST STATION;

AND RECEIVING SAID SIGNALS AT THE FIRST STATION AND DEMODULATING THEM BY SAID FIRST PSEUDO-RANDOM SEQUENCY;

THE SELECTED TIME-ADVANCED SEQUENCE BEING TIME ADVANCED RALATIVE TO THE PRINCIPAL REFERENCE SEQUENCE SO AS TO BE SYNCHRONIZED AT THE FIRST STATION WITH THE FIRST SEQUENCE THERE GENERATED, THE MAGNITUDE OF THE TIME ADVANCE BEING PROPORTIONED TO DOUBLE SAID DISTANCE, AND EQUAL TO THE AMOUNT OF SAID LAG PLUS THE TIME OF SIGNAL TRAVEL BETWEEN SAID STATIONS.