×

TRANSCEIVER-TRANSPONDER-TYPE COMMUNICATIONS SYSTEM

  • US 3,633,158 A
  • Filed: 03/05/1969
  • Issued: 01/04/1972
  • Est. Priority Date: 03/05/1969
  • Status: Expired due to Term
First Claim
Patent Images

1. A code-reading system for demodulating a signal received in response to scanning an array of elements including a spaced array of first-type clocking elements, first- and second-type code elements positioned between the clocking elements, and second-type spacing elements in accordance with a code whereby a binary 1 is represented by a single first-type code element placed between successive clocking elements, and separated from the clocking elements by second-type spacing elements, each of which first-type code elements is so dimensioned to provide in response to scanning a greater duration of a first-type received signal than the duration of a second-type received signal provided in response to scanning the adjacent following secondtype spacing element scanned in the direction of scanning;

  • and a binary 0 is represented by only a single second-type code element placed between successive clocking elements, each of which second-type code elements is so dimensioned that the duration of a second-type received signal provided in response to scanning thereof is greater than the duration of a first-type received signal provided in response to scanning the adjacent preceding clocking element in the direction of scanning, comprising scanning means for scanning the array of elements to provide first-type received signals and second-type received signals in accordance with the coded array;

    clocking pulse generating means for providing a pulsed clocking signal;

    comparing means for comparing a said pulsed clocking signal with first-type received signals, which comparing means provides a first-type signal response for each pulse of the clocking signal with which a first-type received signal is coincident and a second-type signal response for each pulse of the clocking signal for which there is no coincident first-type received signal;

    counting means operatively coupled to the comparing means for counting both successive first-type signal responses and successive second-type signal responses; and

    output means operatively coupled to the comparing means and to the counting means for providing a binary signal each time a first-type signal response immediately preceded by a secondtype signal response is provided from the comparing means, the state of which binary signal is determined by the count of the immediately preceding successive second-type signal responses in relation to the count of the adjacent successive first-type signal responses preceding said immediAtely preceding secondtype signal responses.

View all claims
  • 0 Assignments
Timeline View
Assignment View
    ×
    ×