Remote 2-way transmission audience polling and response system

Abstract

A remote response system includes a central control unit and a plurality of remotely-located response units each having keypads for entering a selection from a user. The central control unit sequentially transmits distinct address words and includes redundant receivers for receiving data words transmitted by response units. Each response unit becomes powered-up upon the entry of a user response and transmits a data word, corresponding to the user selection, upon receipt of its unique address word. The central control unit examines the validity of each data bit received and the validity of an entire data word to determine if both a character and its complement are received. If a valid data word is received, the central control unit transmits an acknowledge bit, which powers-down the response unit that sent the valid word. Each response unit transmits its data word simultaneously with the central control unit transmitting the address word for the next unit that is to respond with the transmissions occurring over distinct frequency channels. A clock signal for controlling data word serial bit transmission is derived at each response unit from the address word signal.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows: 
     
       1. A remote response system comprising: a central control unit including address word transmitting means for sequentially transmitting a plurality of distinct address words and data word receiving means for receiving data words;   a plurality of response units located remote from said central control unit, each of said response units including data entry means for receiving an inputted data word, address word receiving means for receiving said address words transmitted from said central control unit, circuit means responsive to said address word receiving means for identifying a particular one of said address words that have been assigned to that particular one of said response units and data word transmitting means responsive to said data entry means and said circuit means for transmitting a data word from said data entry means to said central control unit in response to identification of a particular address word assigned to that particular remote unit; and   said central control unit further including acknowledging means for examining data words received by said data word receiving means and identifying that a data word received from one of said response units is valid and for transmitting an acknowledge message to the one of said response units sending the valid data word.   
     
     
       2. The response system in claim 1 in which said data word transmitting means includes a data word transmitter and energizing means for energizing said data word transmitter, said energizing means being actuated in response to the occurrence of both the receipt of a data word by said data entry means and the identification of the one of said address words assigned to that particular one of said response units, said energizing means being deactuated in response to an acknowledge message being transmitted by said acknowledging means. 
     
     
       3. The response system in claim 2 in which said energizing means includes a gatable switch means responsive to a gate signal for applying power from a power source to said data word transmitter, a first latch means for connecting said power source to, said gatable switch means in response to the receipt of an inputted data word by said data entry means and a second latch means for supplying a gate signal to said gatable switch means in response to said circuit means identifying the one of said address words assigned to that particular one of said response units and for terminating said supplying of a gate signal in response to said data word transmitter transmitting a data word. 
     
     
       4. The response system in claim 3 in which said first latch means is responsive to an acknowledge message being sent by said central control unit for disconnecting said power source from said gatable switch means. 
     
     
       5. The response system in claim 1 in which said address word transmitting means includes means for broadcasting an RF signal at a first predetermined frequency modulated with said address words and said data word transmitting means includes means for broadcasting an RF signal at a second predetermined frequency different than said first frequency and modulated with a data word and wherein one of said response units transmits a data word simultaneously with said central control unit transmitting the address word for another one of said response units. 
     
     
       6. The response system in claim 1 in which said address word transmitting means includes means for broadcasting a first RF signal at a first predetermined frequency, said first RF signal being modulated with said address words and said data word transmitting means includes means for broadcasting a second RF signal at a second predetermined frequency different than said first frequency, said second RF signal being modulated with a data word and wherein each one said response units transmits said second RF signal simultaneously with said central control unit transmitting said first RF signal modulated with the address word assigned to another one of said response units. 
     
     
       7. The response system of claim 5 in which said circuit means further includes clock generating means responsive to said address receiving means for generating clock pulses synchronized with elements of said address words and wherein said data word transmitting means is responsive to said clock pulses in order to establish a time reference for transmitting elements of said data word. 
     
     
       8. The response system in claim 6 in which said circuit means further includes clock generating means responsive to said address receiving means for generating clock pulses synchronized with elements of said address words and wherein said data word transmitting means is responsive to said clock pulses in order to establish a time reference for transmitting elements of said data word. 
     
     
       9. The response system in claim 1 in which said circuit means further includes clock generating means responsive to said address receiving means for generating clock pulses synchronized with elements of said address words and wherein said data word transmitting means is responsive to said clock pulses in order to establish a time reference for transmitting elements of said data word. 
     
     
       10. The response system in claim 1 in which said address word transmitting means includes memory means for storing a plurality of said address words and retrieving means for retrieving address words from said memory means and transmitting individual ones of said retrieved address words in a sequential manner and wherein said retrieving means repetitively cycles through said address words irrespective of which of said response units have sent valid data words. 
     
     
       11. The response system in claim 1 in which said data word transmitting means includes means for frequency modulating an RF signal with said data word and said acknowledging means includes means for sampling said RF signal received by said data word receiving means for a predetermined sampling period and for determining that said RF signal is within one of two predetermined frequency ranges during said sampling period. 
     
     
       12. The response system in claim 11 in which said data word transmitting means includes means for transmitting a data word as a character and a complement of said character and in which said acknowledging means includes means for determining that a character and its complement are in a data word received by said data word receiving means. 
     
     
       13. A remote response system comprising: a central control unit and a plurality of response units located remote from said control unit, said central control unit including address word transmitting means for transmitting a plurality of distinct address words at a given rate and data word receiving means for receiving data words transmitted from said response units; each or said response units including; address word receiver means tar receiving said elements of address words from said central control unit at said given rate;   address identification means responsive to said address word receiver means for identifying an address word assigned to the particular response unit;   clock generating means responsive to said address word receiver means for generating a clock signal having elements that are generated in synchronism with elements of each of said address words:   data entry means adapted to actuation by a user for   receiving and storing data words;   data transmitting means for transmitting data words from said data entry means to the central control unit; and   transfer means responsive to said clock signal and to said address identification means for transferring data words from said data entry means to said data transmitting means when said address word assigned to the particular response unit is identified and at a rate that is synchronized with the rate of receipt or said address word elements whereby the rate of data word transmission is established by the central control unit at said given rate.   
     
     
       14. The response system in claim 13 in which each of said response units further includes acknowledge message identification means responsive to said address word receiver means for identifying a particular element of an address word, wherein said particular element is an acknowledge message, each said response unit further including energizing means for energizing said data transmitting means to transmit a data word to said central control unit, said energizing means including first and second latches and means responsive to both said latches being set for energizing said transmitting means, said first latch being set in response to said address identification means identifying said address word that is assigned to the particular response unit, said second latch being set in response to actuation of said data entry means by a user, and wherein both said first and second latches are reset in response to said acknowledge message identification means identifying an acknowledge message, whereby data words are transmitted during the receipt of the address word immediately after the address word that is unique to the particular response unit and will be repeated in this manner until an acknowledge message is received. 
     
     
       15. The response system in claim 14 in which each of said response units includes indicating means for producing an indication to a user, and a third latch for actuating said indicating means, said third latch being set in response to said second latch being set and being reset in response to said address identification means identifying said address word assigned to the particular response unit. 
     
     
       16. A method of retrieving data words at a central control unit from a plurality of remote response units comprising the steps of: receiving user inputted data words in at least one of said remote response units;   placing each one of said remote response units having a data word obtained during said step or receiving in a first mode indicative of that particular response unit having a data word to be retrieved;   transmitting from said central control unit to substantially all remote response units, distinct address words in a sequential manner, said address words having a predetermined number of elements;   at each one of said remote response units, receiving said address words and identifying when an address word is received that is assigned to that particular remote response unit:   transmitting from each response unit which is in said first mode a data word during an interval after receipt of the address word assigned to the response unit;   receiving at said central control unit each said data word transmitted by one of said response units and determining if each received data word is a valid data word:   transmitting from said central control unit an acknowledge message in response to determining that a valid data word has been received from one of said response units, to the response unit sending the valid data word; and   placing a response unit that is in said tint mode in a second mode in response to that response unit receiving an acknowledge message transmitted by said central control unit, said second mode being indicative of that response unit not having a data word to be retrieved.   
     
     
       17. The method in claim 16 in which said step of transmitting an acknowledge message includes transmitting an acknowledge element after determining that a valid data word has been received and during said interval after receipt of the address word assigned to that particular response unit. 
     
     
       18. The method in claim 17 in which said step of transmitting an acknowledge message further includes simultaneously transmitting said acknowledge element to all response units and in which said step of placing a response unit in a second mode includes causing the response unit that transmitted a data word in the interval during which the acknowledge element is being transmitted to respond to the acknowledge element by switching from said tint mode to said second mode. 
     
     
       19. The method in claim 18 in which said step of transmitting from said central control unit includes broadcasting a first RF signal at a first predetermined frequency and said step of transmitting from each response unit includes broadcasting a second RF signal at a second predetermined frequency different from said first RF signal and wherein said first and second RF signals are broadcast concurrently. 
     
     
       20. The method in claim 16 in which said step of transmitting address words includes providing distinct address words, each being assigned to a different one of said response units, and repetitively cycling through all said address words irrespective of the result of said step of determining if a valid data word is received. 
     
     
       21. The method in claim 16 in which said step of transmitting from each response unit includes deriving a clock signal from the elements of the address word being transmitted from the central control unit during said step of transmitting from said central control unit and using said clock signal to provide a time reference for controlling the rate at which said data word is being transmitted. 
     
     
       22. The method in claim 16 in which said step of transmitting from each response unit includes transmitting said data word and a complement of said data word and in which said step of determining includes determining if both a data word and its complement have been received. 
     
     
       23. A remote response system comprising: a central control unit including means for transmitting a plurality of distinct address words individually in a sequential manner, receiving means for receiving data words, determining means responsive to said receiving means for determining whether a received data word is valid and acknowledging means responsive to a valid data word being received for transmitting an acknowledge message;   a plurality of response units located remote from said central control unit, each of said response units including: data entry means for receiving input data:   means responsive to said data entry means receiving data for placing said response unit in a first mode indicative of that particular response unit having received data to be transmitted to said central control unit;   receiving means for receiving said address words transmitted from said central control unit and determining if an address word is a predetermined address word assigned to that particular response unit;   data word transmitting means responsive to said receiving means receiving the address word assigned to that particular response unit and to that particular response unit being in said first mode for transmitting a data word representative of said data to said central control unit; and   means responsive to said acknowledge message for switching said response unit from said first mode to a second mode indicative of that particular response unit not having data to be transmitted to said central control unit.     
     
     
       24. The response system in claim 23 in which said acknowledging means transmits said acknowledge message substantially concurrently to all said response units and in which said means responsive to said acknowledge message includes means responsive to that particular response unit being the most recent response unit to have transmitted a data word and thereby the one that sent the data word determined by said determining means to be valid for switching that particular response unit from said first mode to said second mode. 
     
     
       25. The response system in claim 24 in which said central control unit transmitting means includes means for broadcasting a first RF signal at a first predetermined frequency and said response unit transmitting means includes means for broadcasting a second RF signal at a second predetermined frequency different from said first frequency wherein said first and second RF signals are broadcast concurrently. 
     
     
       26. The response system in claim 23 in which said central control unit transmitting means includes means for repetitively cycling sequentially through all the distinct address words assigned to response units irrespective of said determining means. 
     
     
       27. The response system in claim 23 in which each said remote unit further includes means responsive to said receiving means for deriving a clock signal from address words and said response unit transmitting means is responsive to said clock signal for transmitting a data word, synchronously with said central control unit transmitting an address word. 
     
     
       28. A remote response system comprising: a central control unit including control unit transmitting means for individually transmitting a plurality of distinct address words in a sequential manner and control unit receiving means for receiving data words, said control unit transmitting means including means for serially transmitting elements of said address words;   a plurality of response units located remote from said central control unit, each of said response units including data entry means for receiving and storing input data, response unit receiving means for receiving said address words and determining if an address word is a predetermined address word assigned to that particular response unit and transmitting means responsive to said receiving means receiving the address word assigned to that particular response unit for transmitting a data word representative of data stored in said data entry means said data word made up of data word elements;   each of said response units further including clock generating means responsive to said response unit receiving means for generating a clock signal synchronized with said elements of said address words transmitted by said control unit transmitting means and transfer means responsive to said clock signal for serially transferring said data word elements from said data entry means to said response unit transmitting means such that each response unit transmitting means transmits said data word elements synchronized with the elements of address words being transmitted by said central control unit during the interval immediately after the address word assigned to that particular response unit is transmitted by said central control unit.   
     
     
       29. The response system in claim 28 in which said central control unit transmitting means includes means for broadcasting a first RF signal at a first predetermined frequency and said response unit transmitting means includes means for broadcasting a second RF signal at a second predetermined frequency different from said first frequency wherein said first and second RF signals are broadcast concurrently. 
     
     
       30. The response system in claim 28 in which said central control unit further includes determining means responsive to said control unit receiving means for determining whether said data words are valid and acknowledging means responsive to said determining means for causing said control unit transmitting means to transmit an acknowledge message in response to a valid data word. 
     
     
       31. The response system in claim 30 in which said address words and said data words have the same number of elements and in which said acknowledge message is transmitted by said control unit transmitting means as an additional element of the address word being transmitted concurrently with a data word that is determined by said control unit determining means to be valid. 
     
     
       32. The response system in claim 30 in which said response unit transmitting means includes means for transmitting a data word including said data and a complement of said data and in which said determining means is responsive to receipt of a data word and the complement of said data word for determining that the received data word is valid. 
     
     
       33. The response system in claim 31 in which said elements are equally spaced in time. 
     
     
       34. The response system in claim 32 in which said response unit transmitting means includes means for transmitting an RF signal that is frequency-shift-key modulated by a data word and in which said central control unit determining means includes means for counting cycles of a received data word signal and means responsive to said counting means for determining that the number of said cycles within a predetermined period is within one of two predetermined ranges. 
     
     
       35. A method of retrieving data at a central control unit from a plurality of remote response units comprising the steps of: transmitting from said central control unit to said plurality of remote response units a plurality of distinct address words individually in a sequential manner;   receiving at each remote response unit said address words transmitted from said central control unit and identifying an address word that is assigned to that particular remote unit;   transmitting a data word from a remote response unit to said central control unit in response to that particular remote response unit identifying the address word assigned to it;   receiving at said central control unit data words transmitted from said remote response units and determining whether said data words are valid; and   transmitting an acknowledge message from the central control unit to the remote response unit sending the valid data word in response to said central control unit receiving a valid data word.   
     
     
       36. The method in claim 35 in which said step of transmitting a data word occurs substantially concurrently with the transmitting from the central control unit of the address word sequentially transmitted immediately after said address word that is assigned to the remote unit that is transmitting data. 
     
     
       37. The method in claim 36 in which said step of transmitting an acknowledge message occurs after transmitting from the-central control unit said next address word and before transmitting from the central control unit the address word that is sequentially transmitted immediately after said next address word. 
     
     
       38. A method of retrieving data at a central control unit from a plurality of remotely positioned response units comprising the steps of: sequentially transmitting a plurality of distinct address words having elements from said central control unit in a manner that elements of each address word are serially transmitted;   receiving at each of said response units said plurality of distinct address words transmitted from said central control unit;   generating at each of said response units, from the received data words, a clock signal synchronized with said elements of said address words;   receiving user selections at each of said response units and storing each selection as a data word having elements;   serially transmitting said elements of said data word to the central control unit from a response unit upon the central control unit transmitting an address word assigned to that particular response unit and at a rate determined by said clock signal.   
     
     
       39. The method in claim 38 in which said step of sequentially transmitting includes broadcasting a first RF signal at a first predetermined frequency modulated with said address word elements and said step of transmitting said data word includes broadcasting a second RF signal at a second predetermined frequency modulated with said data word and in which said second frequency is different from said first frequency whereby said first and second RF signal are broadcast concurrently. .Iadd. 
     
     
       40.  A remote response system comprising: a central control unit including address word transmitting means for transmitting address words and data word receiving means for receiving data words;   a plurality of response units located remote from said central control unit, each of said response units including data entry means for receiving an inputted data word, address word receiving means for receiving said address words transmitted from said central control unit, circuit means responsive to said address word receiving means for identifying a particular one of said address words that have been assigned to that particular one of said response units and data word transmitting means responsive to said data entry means and said circuit means for transmitting a data word from said data entry means to said central control unit in response to identification of a particular address word assigned to that particular remote unit; and   said central control unit further including acknowledging means for examining data words received by said data word receiving means and identifying that a data word received from one of said response units is valid and for transmitting an acknowledge message to the one of said response units sending the valid data word. .Iaddend..Iadd.   
     
     
       41.  A method of retrieving data words at a central control unit from a plurality of remote response units comprising the steps of: receiving user inputted data words in at least one of said remote response units;   placing each one of said remote response units having a data word obtained during said step of receiving in a first mode indicative of that particular response unit having a data word to be retrieved;   transmitting address words from said central control unit to substantially all remote response units;   at each one of said remote response units, receiving said address words and identifying when an address word is received that is assigned to that particular remote response unit;   transmitting from each response unit which is in said first mode a data word during an interval after receipt of the address word assigned to the response unit;   receiving at said central control unit each said data word transmitted by one of said response units and determining if each received data word is a valid data word;   transmitting from said central control unit an acknowledge message in response to determining that a valid data word has been received from one of said response units, to the response unit sending the valid data word; and   placing a response unit that is in said first mode in a second mode in response to that response unit receiving an acknowledge message transmitted by said central control unit, said second mode being indicative of that response unit not having a data word to be retrieved. .Iaddend..Iadd.   
     
     
       42.  A remote response system comprising: a central control unit including means for transmitting address words, receiving means for receiving data words, determining means responsive to said receiving means for determining whether a received data word is valid and acknowledging means responsive to a valid data word being received for transmitting an acknowledge message;   a plurality of response units located remote from said central control unit, each of said response units including; data entry means for receiving input data;   means responsive to said data entry means receiving data for placing said response unit in a first mode indicative of that particular response unit having received data to be transmitted to said central control unit;   receiving means for receiving said address words transmitted from said central control unit and determining if an address word is assigned to that particular response unit;   data word transmitting means responsive to said receiving means receiving the address word assigned to that particular response unit and to that particular response unit being in said first mode for transmitting a data word representative of said data to said central control unit; and   means responsive to said acknowledge message for switching said response unit from said first mode to a second mode indicative of that particular response unit not having data to be transmitted to said central control unit. .Iaddend..Iadd.     
     
     
       43.  A method of retrieving data at a central control unit from a plurality of remote response units comprising the steps of: transmitting address words from said central control unit to said plurality of remote response units;   receiving at each remote response unit said address words transmitted from said central control unit and identifying an address word that is assigned to that particular remote unit;   transmitting a data word from a remote response unit to said central control unit in response to that particular remote unit identifying the address word assigned to it;   receiving at said central control unit data words transmitted from said remote response units and determining whether said data words are valid; and   transmitting an acknowledge message from the central control unit to the remote response unit sending the valid data word in response to said central control unit receiving a valid data word. .Iaddend.