Wireless communication system including a unique data transmission device

• US 6,721,546 B1
• Filed: 02/27/2001
• Issued: 04/13/2004
• Est. Priority Date: 02/27/2001
• Status: Active Grant

• Current Assignee: Mesa Laboratories Inc.
• Original Assignee: Point Six Wireless LLC (Mesa Laboratories Inc.)
• Inventors: Compton, John I.
• Primary Examiner(s): Urban, Edward F.
• Assistant Examiner(s): Jackson, Blane J.
• Application Number:
  US09/794,415
• Time in Patent Office: 1,141 Days
• Field of Search: 455/91, 455/127.1, 455/127.5, 455/11.1, 455/12.1, 455/517, 455/456.1, 342/357.07, 342/457, 340/988, 340/992, 340/10.1, 340/10.2, 370/310.2, 370/311, 370/389, 370/391, 370/395.2
• US Class Current: 455/91
• CPC Class Codes: G08C 17/00 Arrangements for transmitting signals characterised by the use of a wireless electrical link

Abstract

A microprocessor, powered by a low cost battery, controls a wireless transmitter of a communication system. A sensor senses the value of at least one condition at a predetermined location. The transmitter transmits to a wireless receiver a data packet, which includes the value of the at least one condition, at randomly selected transmission time intervals. Closing of a multiple function push button switch activates an inactive microprocessor to cause its controlled transmitter to transmit irrespective of the selected transmission time interval until the next transmission if the switch is opened before a predetermined period of time elapses or to cause inactivation of the activated microprocessor for the longest available inactive period of time if the switch is held closed for the predetermined period of time.

Claims

1. A method of randomly transmitting data packets to at least one wireless receiver from a wireless transmitter controlled by a microprocessor powered by a battery including:

sensing a value of at least one condition at a predetermined location;

transmitting a data packet having the value of the at least one condition at the predetermined location at varying selected transmission time intervals with only one data packet transmitted during each selected transmission time interval;

using the value of a stored variable number and at least a portion of the value of the at least one condition at the predetermined location at a predetermined time relative to each transmission to provide a random number value for use in determining the selected transmission time interval from the last transmission until a data packet having the value of the at least one condition at the predetermined location is next to be transmitted by the transmitter;

changing the value of the stored variable number after each transmission;

using the changed value of the stored variable number and at least a portion of the value of the at least one condition at the predetermined location at the predetermined time relative to each transmission to change the random number value after each transmission of a data packet by the transmitter;

and using the changed random number value in determining the selected transmission time interval until the next transmission of a data packet by the transmitter.

2. The method according to claim 1 including:

automatically activating the microprocessor at a predetermined fixed time interval;

and automatically inactivating the microprocessor a predetermined time period after each activation unless the selected transmission time interval from the last transmission has elapsed.

3. The method according to claim 2 including providing each data packet with the same identification number.

4. The method according to claim 3 including automatically activating the microprocessor at each of the predetermined fixed time intervals by a timing device external of the microprocessor.

5. The method according to claim 4 including manually selectively activating the microprocessor at any time.

6. The method according to claim 5 including:

storing the variable number in the microprocessor;

and using the sum of the changed value of the variable number after each transmission and at least a portion of the sensed value of the at least one condition at the predetermined location at the predetermined time relative to each transmission to obtain the value of the random number from a look-up table in the microprocessor for use in determining the selected transmission time interval until the next transmission of a data packet.

7. The method according to claim 6 including changing the value of the at least one condition at the predetermined location to be transmitted each time that its value changes a predetermined amount between transmissions.

8. The method according to claim 5 including:

manually activating the microprocessor by closing a manually movable switch;

and utilizing the time that the manually movable switch is closed to determine whether the microprocessor causes activation of the transmitter irrespective of whether the selected transmission time interval has elapsed or causes inactivation of the microprocessor for the longest available period of time when the manually movable switch remains closed for a predetermined period of time without the microprocessor activating the transmitter.

9. The method according to claim 5 including:

storing the variable number in the microprocessor;

and using the sum of the changed value of the variable number after each transmission and the three least significant bits of the sensed value of the at least one condition at the predetermined location at the predetermined time relative to each transmission to obtain the value of the random number from a look-up table in the microprocessor for use in determining the selected transmission time interval until the next transmission of a data packet.

10. The method according to claim 1 including:

storing the variable number in the microprocessor;

and using the sum of the changed value of the variable number after each transmission and at least a portion of the sensed value of the at least one condition at the predetermined location at the predetermined time relative to each transmission to obtain the value of the random number from a look-up table in the microprocessor for use in determining the selected transmission time interval until the next transmission of a data packet.

11. The method according to claim 1 including:

storing the variable number in the microprocessor;

and using the sum of the changed value of the variable number after each transmission and the three least significant bits of the sensed value of the at least one condition at the predetermined location at the predetermined time relative to each transmission to obtain the value of the random number from a look-up table in the microprocessor for use in determining the selected transmission time interval until the next transmission of a data packet.

12. The method according to claim 1 including:

manually activating the microprocessor by closing a manually movable switch;

and utilizing the time that the manually movable switch is closed to determine whether the microprocessor causes activation of the transmitter irrespective of whether the selected transmission time interval has elapsed or causes inactivation of the microprocessor for the longest available period of time when the manually movable switch remains closed for a predetermined period of time without the microprocessor activating the transmitter.

13. The method according to claim 1 including changing the value of the at least one condition at the predetermined location to be transmitted each time that its value changes a predetermined amount between transmissions.

14. The method according to claim 1 including:

sensing the value of the at least one condition at the predetermined location after each transmission is completed and the microprocessor is inactivated;

and saving the sensed value for use as the sensed value of the at least one condition at the predetermined location in the data packet during the next transmission.

15. A method of randomly transmitting data packets to at least one wireless receiver from each of a plurality of wireless transmitters with each of the transmitters controlled by a separate microprocessor powered by a separate battery including:

sensing a value of at least one condition at a different predetermined location for each of the transmitters;

transmitting a data packet having the value of the at least one condition at each of the different predetermined locations at varying selected transmission time intervals by a different one of the transmitters with only one data packet transmitted during each selected transmission time interval for each of the transmitters, each of the transmitters transmitting independently of all of the other transmitters;

using the value of a stored variable number for each of the microprocessors independently of all of the other microprocessors and at least a portion of the value of the at least one condition at each of the different predetermined locations at a predetermined time relative to each transmission corresponding to a specific microprocessor to provide a random number value for use in determining the selected transmission time interval from the last transmission by the transmitter controlled by its specific microprocessor until a data packet having the value of the at least one condition at one of the different predetermined locations for the specific microprocessor is next to be transmitted by the transmitter controlled by its specific microprocessor;

changing the value of the stored variable number for each of the different microprocessors after each transmission by the transmitter controlled by its specific microprocessor;

using the changed value of the stored variable number in each specific microprocessor and at least a portion of the value of the at least one condition at each of the different predetermined locations at the predetermined time relative to each transmission corresponding to a specific microprocessor to change the random number value after each transmission of a data packet by the transmitter controlled by its specific microprocessor;

and using the changed random number value in determining the selected transmission time interval until the next transmission of a data packet by the transmitter controlled by its specific microprocessor.

16. The method according to claim 15 including:

automatically activating each of the microprocessors separately at a predetermined fixed time interval that is not necessarily the same for each of the microprocessors;

and automatically inactivating each of the microprocessors separately a predetermined time period after each activation unless the selected transmission time interval for the next transmission from the last transmission by the transmitter powered by the specific microprocessor has elapsed.

17. The method according to claim 16 including providing the data packets transmitted by each of the transmitters with a different identification number than the data packets transmitted by all of the other transmitters.

18. The method according to claim 17 including using a separate timing device for each of the microprocessors with each of the timing devices being external of its specific microprocessor for automatically activating the specific microprocessor independently of all of the other microprocessors at each of its predetermined fixed time intervals.

19. The method according to claim 18 including manually selectively activating any of the microprocessors independently of all of the other microprocessors.

20. The method according to claim 19 including:

storing the variable number for each of the microprocessors in the specific microprocessor independently of all of the other microprocessors;

and using the sum of the changed value of the variable number stored in the specific microprocessor after each transmission by the transmitter controlled by its specific microprocessor and at least a portion of the sensed value of the at least one condition at the specific different predetermined location at the predetermined time relative to each transmission by the transmitter controlled by its specific microprocessor to obtain the value of the random number from a look-up table in the specific controlling microprocessor for use in determining the selected transmission time interval until the next transmission of a data packet by the transmitter controlled by its specific microprocessor.

21. The method according to claim 20 including changing the value of the at least one condition at any of the different predetermined locations independently of all of the other different predetermined locations when its value changes a predetermined amount for transmission of the changed value the next time that its transmitter transmits.

22. The method according to claim 19 including:

storing the variable number for each of the microprocessors in the specific microprocessor independently of all of the other microprocessors;

and using the sum of the changed value of the variable number stored in the specific microprocessor after each transmission by the transmitter controlled by its specific microprocessor and the three least significant bits of the sensed value of the at least one condition at the specific different predetermined location at the predetermined time relative to each transmission by the transmitter controlled by its specific microprocessor to obtain the value of the random number from a look-up table in the specific controlling microprocessor for use in determining the selected transmission time interval until the next transmission of a data packet by the transmitter controlled by its specific microprocessor.

23. The method according to claim 19 including:

manually activating each of the microprocessors independently of all of the other microprocessors by closing a manually movable switch for the specific microprocessor;

and utilizing the time that the manually movable switch is closed to determine whether the activated microprocessor causes activation of the transmitter controlled by the activated microprocessor irrespective of whether the selected transmission time interval has elapsed or inactivates the activated microprocessor for the longest available period of time when the manually movable switch remains closed for a predetermined period of time without the activated microprocessor activating the transmitter it controls.

24. The method according to claim 16 including:

storing the variable number for each of the microprocessors in the specific microprocessor independently of all of the other microprocessors;

and using the sum of the changed value of the variable number stored in the specific microprocessor after each transmission by the transmitter controlled by its specific microprocessor and at least a portion of the sensed value of the at least one condition at the specific different predetermined location at the predetermined time relative to each transmission by the transmitter controlled by its specific microprocessor to obtain the value of the random number from a look-up table in the specific controlling microprocessor for use in determining the selected transmission time interval until the next transmission of a data packet by the transmitter controlled by its specific microprocessor.

25. The method according to claim 16 including:

storing the variable number for each of the microprocessors in the specific microprocessor independently of all of the other microprocessors;

and using the sum of the changed value of the variable number stored in the specific microprocessor after each transmission by the transmitter controlled by its specific microprocessor and the three least significant bits of the sensed value of the at least one condition at the specific different predetermined location at the predetermined time relative to each transmission by the transmitter controlled by its specific microprocessor to obtain the value of the random number from a look-up table in the specific controlling microprocessor for use in determining the selected transmission time interval until the next transmission of a data packet by the transmitter controlled by its specific microprocessor.

26. The method according to claim 15 including:

manually selectively activating any of the microprocessors independently of all of the other transmitter by closing a manually movable switch;

and utilizing the time that the manually movable switch is closed to determine whether the activated microprocessor is inactivated for the longest available period of time when the manually movable switch remains closed for a predetermined period of time or the activated microprocessor causes activation of the transmitter controlled by the activated microprocessor irrespective of whether the selected transmission time interval has elapsed when the manually movable switch is opened prior to the predetermined period of time elapsing.

27. The method according to claim 15 including changing the value of the at least one condition at any of the different predetermined locations independently of all of the other different predetermined locations when its value changes a predetermined amount for transmission of the changed value the next time that its transmitter transmits.

28. A communication system including:

a wireless transmitter for transmitting data packets to at least one wireless receiver;

a microprocessor controlling said transmitter;

a battery for powering said microprocessor;

a sensor for sensing a value of at least one condition at a predetermined location;

said microprocessor using the value of a stored variable number and at least a portion of the value of the at least one condition at the predetermined location at a predetermined time relative to each transmission for providing a random number value for use in determining a selected transmission time interval from the last transmission until the next transmission by said transmitter of a data packet having the value of the at least one condition at the predetermined location;

and said microprocessor having an algorithm for changing the random number value after each transmission of a data packet by said transmitter.

29. The communication system according to claim 28 including:

said microprocessor having a memory;

said memory of said microprocessor storing the variable number having its value changed in response to each transmission of a data packet by said transmitter;

said memory of said microprocessor storing the sensed value of the at least one condition at the predetermined location;

said microprocessor having a look-up table with a plurality of random numbers and one of the plurality of random number values corresponding to the value of each of the sums of the value of the variable number and at least a portion of the value of the at least one condition at the predetermined location after the last transmission;

said microprocessor utilizing the sum of the value of the variable number and at least a portion of the value of the at least one condition at the predetermined location stored in said memory after the last transmission to obtain the random number value from the look-up table for use in determining the selected transmission time interval until the next transmission of the data packet from the last transmission;

and said microprocessor using the sum of the value of a base transmission time interval and a predetermined portion of the value of the number from the look-up table as the selected transmission time interval until the next transmission of the data packet.

30. The communication system according to claim 29 in which:

said sensor senses the value of the at least one condition at the predetermined location after each transmission of the data packet by said transmitter is completed;

and said microprocessor is inactivated after completion of each transmission of the data packet by said transmitter and before said sensor senses the value of the at least one condition at the predetermined location after completion of each transmission of the data packet by said transmitter.

31. The communication system according to claim 30 in which:

said sensor includes a memory;

said sensor stores in said memory of said sensor the value of the at least one condition at the predetermined location sensed after completion of each transmission of the data packet by said transmitter and inactivation of said microprocessor;

and said sensor is inactivated upon completion of storing in said memory of said sensor the value of the at least one condition at the predetermined location sensed after each transmission of the data packet by said transmitter and after said microprocessor is inactivated.

32. The communication system according to claim 31 in which the algorithm for changing the random number value after each transmission of a data packet by said transmitter is software.

33. The communication system according to claim 32 including a timing device for automatically activating said microprocessor at a predetermined fixed time interval.

34. The communication system according to claim 33 in which said timing device is external of said microprocessor.

35. The communication system according to claim 29 including:

a manually movable switch for selectively activating said microprocessor when said manually movable switch is closed;

and said microprocessor having an algorithm for inactivating said microprocessor after a predetermined period of time has elapsed from manual closing of said manually movable switch or for activating said transmitter to transmit a data packet when said manually movable switch is opened prior to elapsing of the predetermined period of time.

36. The communication system according to claim 35 in which the algorithm is software to inactivate said microprocessor after said microprocessor is activated when said switch is manually closed for the predetermined period of time or to activate said transmitter to transmit a data packet when said manually movable switch is opened prior to elapsing of the predetermined period of time.

37. The communication system according to claim 36 in which:

said sensor senses the value of the at least one condition at the predetermined location after completion of each transmission of the data packet by said transmitter;

and said microprocessor is automatically inactivated after completion of each transmission of the data packet by said transmitter and before said sensor senses the value of the at least one condition at the predetermined location after completion of each transmission of the data packet by said transmitter.

38. The communication system according to claim 29 in which:

said sensor senses the value of the at least one condition at the predetermined location after completion of each transmission of the data packet by said transmitter;

and said microprocessor has an algorithm to inactivate said microprocessor after completion of each transmission of the data packet by said transmitter and before said sensor senses the value of the at least one condition at the predetermined location after completion of each transmission of the data packet by said transmitter.

39. The communication system according to claim 29 in which the algorithm for changing the random number value after each transmission of a data packet by said transmitter is software.

40. The communication system according to claim 28 including:

a manually movable switch for selectively activating said microprocessor when said manually movable switch is closed;

and said microprocessor having an algorithm for inactivating said microprocessor after a predetermined period of time has elapsed from manual closing of said manually movable switch or for activating said transmitter to transmit a data packet when said manually movable switch is opened prior to elapsing of the predetermined period of time.

41. The communication system according to claim 40 in which the algorithm is software to inactivate said microprocessor after said microprocessor is activated when said switch is manually closed for the predetermined period of time or to activate said transmitter to transmit a data packet when said manually movable switch is opened prior to elapsing of the predetermined period of time.

42. The communication system according to claim 41 in which:

said sensor senses the value of the at least one condition at the predetermined location after completion of each transmission of the data packet by said transmitter;

and said microprocessor is automatically inactivated after completion of each transmission of the data packet by said transmitter and before said sensor senses the value of the at least one condition at the predetermined location after completion of each transmission of the data packet by said transmitter.

43. The communication system according to claim 42 in which:

said sensor includes a memory;

said sensor stores in said memory of said sensor the value of the at least one condition at the predetermined location sensed after completion of each transmission of the data packet by said transmitter and automatic inactivation of said microprocessor;

and said sensor is inactivated upon completion of storing the value of the at least one condition at the predetermined location sensed after each transmission of the data packet by said transmitter is completed and after said microprocessor is automatically inactivated.

44. The communication system according to claim 28 including:

said microprocessor having a memory;

said memory of said microprocessor storing the variable number having its value changed in response to each transmission of a data packet by said transmitter;

said memory of said microprocessor storing the sensed value of the at least one condition at the predetermined location;

said microprocessor having a look-up table with a plurality of random numbers and one of the plurality of random number values corresponding to the value of each of the sums of the value of the variable number and the three least significant bits of the value of the at least one condition at the predetermined location after the last transmission;

said microprocessor utilizing the sum of the value of the variable number and the value of the three least significant bits of the at least one condition at the predetermined location after the last transmission to obtain the random number value from the look-up table for use in determining the selected transmission time interval until the next transmission of the data packet;

and said microprocessor using the sum of the value of a base transmission time interval and the three least significant bits of the value of the number from the look-up table as the selected transmission time interval until the next transmission of the data packet.

45. The communication system according to claim 28 in which the algorithm for changing the random number value after each transmission of a data packet by said transmitter is software.

46. The communication system according to claim 28 in which said microprocessor includes:

first using means for using a stored variable number value and at least a portion of the value of the at least one condition at the predetermined location at a predetermined time relative to each transmission to provide a random number value for use in determining the selected transmission time interval from the last transmission until a data packet having the value of the at least one condition at the predetermined location is next to be transmitted by said transmitter;

changing means for changing the value of the stored variable number after each transmission of a data packet by said transmitter;

second using means for using the changed value of the stored. variable number and at least a portion of the value of the at least one condition at the predetermined location at the predetermined time relative to each transmission to change the random number value after each transmission of a data packet by said transmitter;

and third using means for using the changed random number value in determining the selected transmission time interval until the next transmission of a data packet by said transmitter.