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

• Current Assignee: Jerome D. Heibel
• Original Assignee: Jerome D. Heibel
• Inventors: Heibel, Jerome D.
• Primary Examiner(s): Claffy, Kathleen H.
• Assistant Examiner(s): Myers, Randall P.
• Application Number:
  US04/804,577
• Time in Patent Office: 1,035 Days
• Field of Search: 340/32,34,38,38P,38S,39,38R,38L 325/16,112 250/199 343/6.5,6.5SS,12MD,1CL,112TC,6.5R,5R,6R,5DP,6.5LC,6.8LC,17.1R,18D
• US Class Current: 398/170
• CPC Class Codes: B61L 25/041 using reflecting tags
• CPC Class Codes: G01S 17/74 Systems using reradiation of electromagnetic waves other than radio waves, e.g. IFF, i.e. identification of friend or foe
• CPC Class Codes: G08G 1/0965 responding to signals from another vehicle, e.g. emergency vehicle
• CPC Class Codes: G08G 1/096725 where the received information generates an automatic action on the vehicle control
• CPC Class Codes: G08G 1/096758 where no selection takes place on the transmitted or the received information
• CPC Class Codes: G08G 1/096783 where the origin of the information is a roadside individual element
• CPC Class Codes: G08G 1/096791 where the origin of the information is another vehicle

Abstract

A transceiver-demodulator combination in a transceivertransponder-type communications system wherein a pulsed beam of radiant energy is encoded to transmit information originating at a transceiver, and modulated by scanning a passive coded transponder with the beam to reflect to the transceiver information originating at the transponder. The information from the transponder is demodulated by producing in response to a pulsed clocking signal representative of the transmitted beam, a first-type signal response for each clocking pulse with which the reflected beam is coincident and a second-type signal response for each clocking pulse for which there is no coincident reflected beam. Successive first-type responses and successive second-type responses are counted and a binary signal is produced in response to a comparison of successive counts whenever a first-type response immediately preceded by a second-type response is produced. The state of the 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 second-type signal responses.

Claims

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.

2. A code-reading system for demodulating a signal received in response to scanning a coded array of first-type elements and second-type elements wherein the coded array of first-type elements are spaced so that the first-type elements representing coded binary 1'"'"''"'"'s are of greater width in the direction of scanning than the following scanned adjacent second-type elements;

and the first-type elements representing coded binary 0'"'"''"'"'s are of shorter width in the direction of scanning than the following scanned adjacent second-type elements, comprising scanning means for scanning the array of elements to provide a received signal in response to scanning a first-type element;

clock pulse generating means for providing a pulsed clocking signal;

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

counting means operatively coupled to the comparing means for separately 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 second-type 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 second-type signal responses.

3. In a communications system wherein a directional radiant energy beam is scanned across an encoded array of radiant energy reflective elements to provide a reflected beam of radiant energy modulated in accordance with the reflective element array, a transceiver-demodulator combination comprising a source of radiant energy;

a pulse generator for providing a pulsed signal;

a control circuit operatively coupled to the pulse generator for producing a pulsed clocking signal representative of said pulsed signal;

transmitting means operatively coupled to the radiant energy source and to the control circuit for transmitting from the radiant energy source in a directional beam pulsed radiant energy representative of said pulsed signal;

radiant energy receiving means proximate to the transmitting means and directed for receiving reflections of a said transmitted beam, which receiving means produces a received signal in response to received radiant energy;

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

counting means operatively coupled to the comparing means for separately 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 second-type 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 second-type signal responses.

4. A transceiver-dEmodulator combination according to claim 3 for use in a said communications system, wherein said encoded array of reflective elements includes a spaced array of reflective clocking elements, and reflective code elements having nonreflective spacing elements positioned between the clocking elements in accordance with a code whereby a binary 1 is represented by a single reflective code element placed between successive reflective clocking elements, and separated from the reflective clocking elements by nonreflective spacing elements, each of which reflective code elements is so dimensioned to reflect a portion of the scanning bean greater than the portion of the scanning beam not reflected by the adjacent following nonreflective spacing element in the direction of scanning, and a binary 0 is represented by only a single nonreflective code element placed between successive reflective clocking elements, each of which nonreflective code elements is so dimensioned that the portion of the scanning beam not reflected by the nonreflective code element is greater than the portion of the scanning beam reflected by the adjacent preceding clocking element in the direction of scanning;

the output means of which transceiver-demodulator combination comprises means for providing a binary 1 in response to each new succession of first-type signal responses when said count of said immediately preceding successive second-type signal responses is not greater than said count of said adjacent successive first-type signal responses;

means for providing a binary 0 in response to each new succession of first-type signal responses when said count of said immediately preceding successive second-type signal responses is greater than said count of said adjacent successive first-type signal responses; and

gating means which alternately inhibit and enable the registering of said provided binary number in response to each new succession of first-type signal responses and in response to each count of successive second-type signal responses which is greater than said count of said adjacent successive first-type signal responses.

5. A tranceiver-demodulator combination according to claim 3 for use in a said communications system, wherein said encoded array of reflective elements are spaced so that the leading edges in the direction of scanning of the reflective elements are evenly spaced;

wherein each reflective element representing a coded binary 1 is of greater width in the direction of scanning than a following scanned adjacent nonreflective element; and

wherein each reflective element representing a coded binary 0 is of shorter width in the direction of scanning than a following scanned adjacent nonreflective element, the output means of which transceiver-demodulator combination comprises means for providing a binary 1 in response to each new succession of first-type signal responses when said count of said immediately preceding successive second-type signal responses is not greater than said count of said adjacent successive first-type signal responses; and

means for providing a binary 0 in response to each new succession of first-type signal responses when said count of said immediately preceding successive second-type signal responses is greater than said count of said adjacent successive first-type responses.

6. A transceiver-demodulator combination according to claim 3, wherein said directional beam is encoded to convey information to a remote receiver, in which combination the control circuit further comprises means for selectively encoding said pulsed signal to convey discrete information, whereby said pulsed clocking signal is representative of said encoded pulsed signal, and whereby said transmitting means transmit encoded pulsed radiant energy representative of said encoded pulsed signal.

7. A transceiver-demodulator combination according to claim 3, wherein said source of radiant energy compriseS a source of high-intensity light.

8. In a communications system wherein a directional radiant energy beam is scanned across an encoded array of radiant energy reflective elements to provide a reflected beam of radiant energy modulated in accordance with the reflective element array, a transceiver-demodulator combination comprising a source of radiant energy;

a pulse generator for providing a pulsed signal;

a control circuit operatively coupled to the pulse generator for producing a pulsed clocking signal representative of said encoded pulsed signal;

transmitting means operatively coupled to the radiant energy source and to the control circuit for transmitting from the radiant energy source in a directional beam encoded pulsed radiant energy representative of said encoded pulsed signal;

radiant energy receiving means proximate to the transmitting means and directed for receiving reflections of a said transmitted beam, which receiving means produces a received signal in response to received radiant energy;

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

clock pulse generating means for producing a second pulsed clocking signal having a uniform rate essentially the same as the average rate of the first pulsed clocking signal;

detection means operatively coupled to the receiving means and to the clock pulse generating means for recognizing a received signal produced by the receiving means at essentially the same rate as said second pulsed clocking signal and having a unique predetermined binary recognition characteristic, as a received signal produced in response to a pulsed radiant energy beam from a remote transmitter; and

gating means operatively coupled to the detection means and to the comparing means for holding the received signal on a delayed basis, whenever a received signal produced in response to a pulsed radiant energy beam from a remote transmitter is recognized, to enable the comparing means to make said coincidence comparisons between said first clocking signal and a said received signal produced in response to a said pulsed radiant energy beam received from a remote transmitter.

9. A transceiver-demodulator combination according to claim 8, wherein said directional beam is encoded to convey information to a remote receiver, in which combination the control circuit further comprises means for selectively encoding said pulsed signal to convey discrete information, whereby said first pulsed clocking signal is representative of said encoded pulsed signal, and whereby said transmitting means transmit encoded pulsed radiant energy representative of said encoded pulsed signal.

10. A transceiver-demodulator combination according to claim 8 wherein said source of radiant energy comprises a source of high-intensity light.

11. In a communications system wherein a directional light beam is scanned across an encoded array of light-reflective elements to provide a reflected beam of light modulated in accordance with the reflective element array, a transceiver-demodulator combination for providing a said transmitted directional light beam which is encoded to convey information to a remote receiver, comprising a source of high-intensity light;

a pulse generator for providing a pulsed signal;

a control circuit operatively coupled to the pulse generator for selectively encoding said pulsed signal to convey discrete information and for producing a pulsed clocking signal representative of said encoded pulsed signal;

transmitting means operatively coupled to the light source and to the control cirCuit for transmitting from the light source in a directional beam encoded high-intensity short duration light pulses;

light-receiving means proximate to the transmitting means and directed for receiving reflections of a said transmitted beam, which receiving means produces a received signal in response to received light; and

comparing means operatively coupled to the control circuit and to the receiving means for comparing said pulsed clocking signal with a said received signal, which comparing means provides a first-type signal response for each pulse of said pulsed clocking signal with which a said received signal is coincident and a second-type signal response for each pulse of said pulsed clocking signal for which there is no coincident received signal.

12. A communications system wherein a directional radiant energy beam is scanned across an encoded array of radiant energy reflective elements to provide a reflected beam of radiant energy modulated in accordance with the reflective element array and wherein a said transmitted directional beam is encoded to convey information to a remote receiver, which system comprises an encoded array of radiant energy reflective elements;

a source of radiant energy;

a pulse generator for providing a pulsed signal;

a control circuit operatively coupled to the pulse generator for selectively encoding said pulsed signal to convey discrete information and for producing a pulsed clocking signal representative of said encoded pulsed signal;

transmitting means operatively coupled to the radiant energy source and to the control circuit for transmitting from the radiant energy source in a directional beam encoded pulsed radiant energy representative of said encoded pulsed signal;

radiant energy receiving means proximate to the transmitting means and directed for receiving reflections of a said transmitted beam, which receiving means produces a received signal in response to received radiant energy; and

comparing means operatively coupled to the control circuit and to the receiving means for comparing said pulsed clocking signal with a said received signal, which comparing means provides a first-type signal response for each pulse of said pulsed clocking signal with which a said received signal is coincident and a second-type signal response for each pulse of said pulsed clocking signal for which there is no coincident received signal.

13. A communications system according to claim 12, in which the source of radiant energy is a high-intensity light source and in which the transmitting means transmits pulsed light from the light source in a directional beam of high-intensity short duration pulses.

14. A communications method wherein a directional radiant energy beam is scanned across an encoded array of radiant energy reflective elements to provide a reflected beam of radiant energy modulated in accordance with the reflective element array, comprising providing radiant energy;

providing a pulsed signal;

transmitting said radiant energy in a pulsed directional beam in response to said pulsed signal;

producing a pulsed clocking signal representative of said transmitted beam;

receiving reflections of a said transmitted beam, and producing a received signal in response to said received radiant energy, comparing said pulsed clocking signal with said received signal to provide a first-type signal response for each pulse of said pulsed clocking signal with which said received signal is coincident and a second-type signal response for each pulse of said pulsed clocking signal for which there is no coincident received signal;

separately counting both successive first-type signal responses and successive second-type signal responses; and

providing a binary signal each time a first-type signal response immediately preceded by a second-type signal response is provided in response to the comparing step, the state of which 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 second-type signal responses.

15. A communications method wherein a directional radiant energy beam is scanned across an encoded array of radiant energy reflective elements to provide a reflected beam of radiant energy modulated in accordance with the reflective element array, which method comprises providing radiant energy;

providing a pulsed signal;

transmitting said radiant energy in a pulsed directional beam in response to said pulsed signal;

producing a first pulsed clocking signal representative of said transmitted beam;

receiving reflections of a said transmitted beam, and producing a received signal in response to said received radiant energy;

comparing said pulsed clocking signal with said received signal to provide a first-type signal response for each pulse of said pulsed clocking signal with which said received signal is coincident and a second-type signal response for each pulse of said pulsed clocking signal for which there is no coincident received signal;

producing a second pulsed clocking signal having a uniform rate essentially the same as the average rate of the first pulsed clocking signal;

receiving a pulsed energy beam from a remote transmitter and producing a received signal in response to said received pulsed radiant energy beam;

recognizing a received signal produced at essentially the same rate as said second pulsed clocking signal and having a unique predetermined binary recognition characteristic, as a received signal produced in response to a pulsed energy beam received from a remote transmitter; and

holding the received signal on a delayed basis, whenever a received signal produced in response to a pulsed energy beam from a remote transmitter is recognized, to enable coincidence comparisons to be made between said first clocking signal and a said received signal produced in response to a said pulsed radiant energy beam received from a remote transmitter.