Remote response system and data transfer protocol

• US 5,724,357 A
• Filed: 06/24/1994
• Issued: 03/03/1998
• Est. Priority Date: 01/28/1992
• Status: Expired due to Term

• Current Assignee: Fleetwood Furniture Company
• Original Assignee: Fleetwood Group Incorporated
• Inventors: Derks, Harry G.
• Primary Examiner(s): Kizou, Hassan
• Application Number:
  US08/265,843
• Time in Patent Office: 1,348 Days
• Field of Search: 370/8, 370/9, 370/10, 370/94.1, 370/94.2, 370/95.1, 370/95.2, 370/205, 370/212, 370/312, 370/313, 370/314, 370/349, 370/432, 370/449, 375/238, 375/239, 375/259, 375/274, 375/276, 455/2, 455/53.1, 455/54.1, 455/54.2, 341/60, 341/178, 341/182, 434/322, 434/350, 434/351, 434/352, 434/327, 434/336, 340/504, 340/505, 340/825.44, 340/825.52, 340/825.54, 340/825.55, 340/825.57, 340/825.63, 340/825.64, 340/311.1, 340/313, 379/92
• US Class Current: 370/313
• CPC Class Codes: G06F 15/025 adapted to a specific application
• CPC Class Codes: G06Q 30/02 Marketing; Price estimation or determination; Fundraising
• CPC Class Codes: G09B 5/14 with provision for individual teacher-student communication
• CPC Class Codes: G09B 7/06 of the multiple-choice answer-type, i.e. where a given question is provided with a series of answers and a choice has to be made from the answers
• CPC Class Codes: H04H 20/38 Arrangements for distribution where lower stations, e.g. receivers, interact with the broadcast
• CPC Class Codes: H04H 2201/70 characterised in that receivers can be addressed
• CPC Class Codes: H04H 60/15 on receiving information

Abstract

A wireless remote response system includes a base unit which retrieves user-entered responses from a plurality of remote response units, each of which is provided to a user. The base unit transmits a base data package over a wireless communication link to the plurality of remote response units, which decode the base packet and load into memory a portion of the decoded base package at each response unit. Each response unit examines the characters loaded into the memory and determines any character in the portion of the decoded base package that pertains to that particular response unit. Each remote response unit then processes any character that pertains to that particular response unit. Each bit of data exchanged between the base unit and the response unit is encoded as a particular time interval for at least one cycle of a periodic waveform by varying the time interval either between successive rising edges or between successive falling edges of the periodic waveform. Decoding is carried out by measuring the time intervals between rising edges or between falling edges of successive waveforms. It is then determined whether each measured time interval falls within one of at least two distinct non-overlapping time ranges in order to determine a value of each bit.

Claims

1. A wireless method of retrieving at a base unit responses from a plurality of users, said responses being entered in a plurality of remote response units, each user being provided with a response unit, including:

transmitting a base data packet over a wireless communication link to said plurality of remote response units;

decoding said base data packet at each response unit and loading into memory at least a portion of the decoded base data packet at each response unit, wherein said portion of the decoded base packet includes a plurality of characters, at least a portion of said plurality of characters pertaining to different response units;

determining at each response unit any character of said portion of the decoded base data packet that pertains to that particular response unit; and

processing by each remote response unit any character that pertains to that particular remote response unit, including transmitting in a response data packet over a wireless communication link from that particular remote response unit to the base unit any response entered by a user.

2. The method of claim 1 wherein said plurality of characters includes acknowledge characters, each indicative of whether a valid response was previously received from a particular response unit.

3. The method of claim 2, wherein said processing any character includes terminating transmission of a response entered by a user in response to an acknowledge character pertaining to that particular response unit.

4. The method of claim 1 wherein said plurality of characters includes correctness characters, each indicative of whether a previously received response matches a correct answer in an answer key.

5. The method of claim 4 wherein said portion of the decoded base packet includes another plurality of characters pertaining to all said response units, wherein a particular response unit displays a first message contained in said another plurality of characters in response to a given value of the correctness character pertaining to that particular response unit and displays a second message contained in said another plurality of characters in response to a different value of the correctness character pertaining to that particular response unit.

6. The method of claim 4 wherein each response unit displays the value of the correctness character pertaining to that particular response unit.

7. The method of claim 1 wherein said plurality of characters includes microphone activation characters, each for activating an audio communication link with a particular response unit.

8. The method of claim 7 wherein said response units includes a microphone and an audio communication link with said base unit and wherein a particular response unit opens the audio communication link between the microphone of that particular response unit and the base unit in response to said microphone activation character pertaining to that particular response unit.

9. The method of claim 1 wherein said remote response units are divided into groups and wherein said decoded base data packet includes a designation of a group of response units to which said plurality of characters pertain.

10. The method of claim 1 wherein said remote response units are divided into groups and wherein said decoded base data packet includes a first designation of a particular group of response units to which said plurality of characters pertain and a second designation of a particular group of response units to transmit a response data packet.

11. The method of claim 1 wherein said remote response units are divided into groups and wherein said decoded base data packet includes a designation of a particular group of response units to transmit a response data packet.

12. The method of claim 11 including providing a unique identification to each of said number of response units and determining at each of said number of response units a response interval following said base data packet as a function of said designation of a particular group of response units and the identification of a particular response unit.

13. The method of claim 12 wherein said decoded base data packet includes a designation of the number of characters making up a response data packet and wherein said determining is also a function of said number of characters.

14. The method of claim 1 wherein said decoded base data packet includes a designation of the number of characters making up a response data packet.

15. The method of claim 14 wherein each response unit transmits a response data packet having the number of characters designated in said decoded base data packet.

16. The method of claim 1 wherein each of said remote response units includes a microcomputer having erasable memory and wherein said portion of the decoded base data packet includes operating code and wherein said processing includes storing said operating code in said erasable memory for operating said microcomputer.

17. The method of claim 16 wherein said transmitting a response data packet includes transmitting a null response data packet when a user has not entered a response.

18. The method of claim 1 wherein said transmitting a response data packet includes transmitting a null response data packet when a user has not entered a response.

19. The method of claim 1 wherein said portion of the decoded base data packet includes a plurality of characters globally pertaining to a plurality of remote response units.

20. The method of claim 19 including transmitting a plurality of base data packets, each including a plurality of characters globally pertaining to a plurality of remote response units, determining at each remote response unit which of said base data packets is validly received, and transmitting from each said remote response unit an indication of which base data packets were validly received at that remote response unit.

21. The method of claim 20 further including assembling a bit map at said base unit of all base data packets validly received at said remote response units and repetitively retransmitting ones of said base data packets which said bit map indicates were not validly received at at least one said remote response unit.

22. The method of claim 1 wherein said response data packet includes multiple character responses.

23. A wireless method of retrieving at a base unit responses from a plurality of users, said responses being entered in a plurality of remote response units, each user being provided with a response unit, including:

transmitting a base data packet over a wireless communication link that is subject to variation in timing between rising and falling edges of transmitted data from said base unit and receiving the transmitted base data packet by said plurality of remote response units and transmitting a response data packet over a wireless communication link that is subject to variation in timing between rising and falling edges of transmitted data from at least one of said remote response units to said base unit and receiving the transmitted response data packet by said base unit, said response data packet containing any response entered by a user;

wherein at least one of said transmitting a base data packet and transmitting a response data packet includes encoding the respective data packet by varying the time period for at least one cycle of a periodic waveform of a transmitted signal to encode a value of each bit, and wherein at least one of said receiving the transmitted base data packet and receiving the transmitted response data packet includes decoding the respective data by measuring time intervals for at least one cycle of a received signal; and

determining whether each of said time intervals falls within one of at least two distinct, non-overlapping time ranges in order to decode a value of each bit and ignoring the respective data if at least one of said measured time intervals does not fall within one of said distinct, non-overlapping time ranges.

24. The method of claim 23 wherein said at least one cycle of a periodic waveform of a transmitted signal is measured either between successive rising edges or between successive falling edges of the respective waveform.

25. The method of claim 23 wherein said encoding includes determining whether a majority of bits in a data packet are of a value that would be encoded for a longer time period and inverting said bits in said data packet prior to encoding the respective data packet in order to reduce the time required to transmit the data packet.

26. The method of claim 25 wherein said at least one of said transmitting a base data packet and transmitting a response data packet includes transmitting an indication that said bits in said data packet have been inverted.

27. A wireless method of retrieving at a base unit responses from a plurality of users, said responses being entered in a plurality of remote response units, each user being provided with a response unit, including:

transmitting a base data packet over a wireless communication link to said plurality of remote response units, said base data packet including a designation of at least one characteristic of a response data packet;

at least one said response unit responding to said base data packet by transmitting in a response data packet over a wireless communication link any response entered by a user, wherein a characteristic of said response data packet is defined at least in part by said designation, wherein said characteristic is a number of characters making up a response data packet, whereby said response data packet length is controlled with said base data packet.

28. The method of claim 27 wherein said base data packet includes a designation of a characteristic of said base data packet.

29. The method of claim 28 wherein said characteristic of said base data packet is a number of characters making up said base data packet.

30. The method of claim 28 including providing a unique identification to each of said response units and determining at each of said response units a response interval following said base data packet as a function of said characteristic of said base data packet and the unique identification of that response unit.

31. The method of claim 27 including dividing said remote response units into a plurality of groups and wherein said base data packet includes a designation of a group of response units to respond to said base data packet.

32. The method of claim 27 wherein said transmitting a response data packet includes transmitting a null response data packet when a user has not entered a response.

33. A method of communicating a data packet made up of a plurality of data bits over a wireless communication link that is subject to variation in timing between rising and falling edges of transmitted data, including:

encoding the respective data packet by varying the time period either between successive rising edges or between successive falling edges of a periodic waveform of a signal to encode a value of each bit in an encoded data signal;

transmitting the encoded data signal over a wireless communication link that is subject to variation in timing between rising and falling edges of transmitted data;

receiving the transmitted encoded data signal and decoding the received data signal by measuring time intervals either between successive rising edges or between successive falling edges of the received data signal and determining whether each measured time interval falls within one of at least two distinct non-overlapping time ranges in order to decode a value of each bit; and

determining whether a majority of bits in a data packet are of a value that would be encoded for a longer time period and inverting said bits in said data packet prior to encoding in order to reduce the time required to transmit a data word.

34. The method of claim 33 including transmitting an indication that said bits in a data packet have been inverted.

35. A wireless remote response system comprising:

a base unit, a plurality of remote response units and a wireless communication link between said base unit and each of said response units;

a first microcomputer in said base data programmed to assemble a base data packet, encode said base data packet and communicate the encoded base data packet over said communication link to said plurality of remote response units;

a second microcomputer in each of said remote response units programmed to decode a base data packet received from said base unit, to load into a memory a portion of the decoded base data packet wherein said portion of the decoded base packet includes a plurality of characters, at least a portion of said plurality of characters pertaining to different response units, and said second microcomputer in each of said remote response units programmed to determine any character of said portion of the decoded base packet that pertains to that particular response unit;

an input device in each of said remote response units for receiving a user response selection;

each said second microcomputer further programmed to process any character that in said memory pertains to that particular response unit and to assemble a response data packet in response to a user entering a selection with said input device, encode the response data packet and transmit the encoded response data packet over the wireless communication link from that particular response unit to the base unit; and

said first microcomputer programmed to decode response data packets received from each of said response units.

36. The system in claim 35 wherein said plurality of characters includes acknowledge characters, each indicative of whether said base unit receives a valid response data packet from a particular response unit.

37. The system in claim 36 wherein said second microcomputer is programmed to discontinue transmission of a response data packet when that second microcomputer determines an acknowledge character in said portion of the decoded base data packet that pertains to that particular response unit.

38. The system in claim 35 wherein said plurality of characters includes correctness characters, each indicative of whether a previously received response matches a correct answer in an answer key.

39. The system of claim 38 wherein the portion of the decoded base packet includes another plurality of characters pertaining to all said response units, wherein said second microcomputer of a particular response unit is programmed to display a first message contained in said another plurality of characters in response to a given value of the correctness character pertaining to that particular response unit and to display a second message contained in said another plurality of characters in response to a different value of the correctness character pertaining to that particular response unit.

40. The system in claim 38 wherein said second microcomputer in each response unit is programmed to display the value of the correctness character pertaining to that particular response unit.

41. The system in claim 35 wherein said plurality of the character includes a microphone activation character, each for activating an audio communication channel with a particular response unit.

42. The system in claim 41 wherein said response units include a microphone and an audio communication channel with a base station and wherein said second microcomputer of a particular response unit opens the audio communication channel between the microphone of that particular response unit and the base station in response to said microphone activation character pertaining to that particular response unit.

43. The system in claim 35 wherein said remote response units are divided into groups and wherein said decoded base data packet includes a designation of a group of response units to which said plurality of characters pertain.

44. The system in claim 35 wherein said remote response units are divided into groups and wherein said decoded base data packet includes a first designation of a group of response units to which said plurality of characters pertain and a second designation of a group of response units to transmit response data packets.

45. The system in claim 35 wherein said remote response units are divided into groups and wherein said decoded base data packet includes a designation of a group of response units to transmit response data packets.

46. The system in claim 45 wherein each of said response units is assigned a unique identification and wherein said second microcomputer is programmed to determine a response interval following said base data packet within which the associated response unit is to transmit a response data packet as a function of said designation of a particular group of response units and the unique identification of a particular response unit.

47. The system in claim 35 wherein said decoded base data packet includes a designation of a number of characters making up said base data packet and wherein said second microcomputer determines said response interval as a function of said number of characters.

48. The system in claim 35 wherein said decoded base data packet includes a designation of the number of characters making up the response data packet and wherein said second microcomputer is programmed to assemble a response data packet having said number of characters.

49. The system in claim 35 wherein said portion of the decoded base data packet includes operating code and wherein said second microcomputer is programmed to store said operating code in memory for use in operating said second microcomputer.

50. The system in claim 35 wherein said second microcomputer is programmed to assemble a null response data packet not including a selection when a user has not entered a selection, to encode the null response data packet and transmit the encoded null response data packet over the wireless communication link from that particular response unit to the base unit.

51. The system in claim 35 wherein said response data packet includes user selections made up of a plurality of characters.

52. The system in claim 35 wherein each of said first and second microcomputers is programmed to encode the respective data packet by varying the time period either between successive rising edges or between successive falling edges of a periodic waveform to encode a value of each bit making up the data packet, and decode the respective data packet by measuring time intervals either between successive rising edges or between successive falling edges of a received signal.

53. The system in claim 52 wherein each of said first and second microcomputers is further programmed to determine whether each measured time interval falls with in one of at least two distinct non-overlapping time ranges to decode a value of each bit.

54. The system in claim 52 wherein each of said first and second microcomputers is programmed to determine whether a majority of bits in a data packet are of a value that would be encoded for a longer time period and to invert said bits of said data packet prior to encoding in order to reduce the time required to transmit a data packet.

55. The system in claim 54 wherein each of said first and second microcomputers is programmed to transmit an indication that said bits in a data packet have been inverted.

56. The system in claim 35 wherein said first microcomputer is programmed to assemble, encode, and communicate a plurality of base data packets, each including a plurality of characters globally pertaining to a plurality of said remote response units, and wherein each said second microcomputer of said plurality of remote response units is programmed to determine which of said base data packets is validly received and to assemble, encode, and transmit a response data packet including indications of which base data packets were validly received at that remote response unit.

57. The system in claim 56 wherein said first microcomputer is programmed to assemble a bit map from said response data packets and to repetitively retransmit ones of said base data packets which said bit map indicates were not validly received.