Multi-detection of heartbeat to reduce error probability

• US 7,394,791 B2
• Filed: 06/12/2002
• Issued: 07/01/2008
• Est. Priority Date: 12/17/1997
• Status: Expired due to Term

• Current Assignee: Apple Inc.
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Proctor, James A. Jr.
• Primary Examiner(s): Chan; Wing
• Assistant Examiner(s): JONES, PRENELL P
• Application Number:
  US10/171,378
• Publication Number:
  US 20030095517A1
• Time in Patent Office: 2,211 Days
• Field of Search: 370328-338, 370/347, 370/441, 370/445, 370/235, 370/442, 370/461, 370/352, 370/252, 370/465, 370/342, 370/320, 370/230, 370/350, 370/356, 370/389, 455421-425, 455/445, 455/454, 455/466, 455/509, 455/517, 455/418, 375/344, 375/130, 375/222, 375/142, 379/156, 379/198, 379/142, 379/165, 342/465, 709/203, 709/217, 709/219
• US Class Current: 370/335
• CPC Class Codes: H04B 1/7075 with code phase acquisition
• CPC Class Codes: H04J 13/0077 Multicode, e.g. multiple codes assigned to one user
• CPC Class Codes: H04J 13/16 Code allocation
• CPC Class Codes: H04L 1/0007 by modifying the frame length
• CPC Class Codes: H04L 1/1809 Selective-repeat protocols
• CPC Class Codes: H04L 25/14 Channel dividing arrangements , i.e. in which a single bit stream is divided between several baseband channels and reassembled at the receiver
• CPC Class Codes: H04L 27/2601 Multicarrier modulation systems
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 7/06 the synchronisation signals differing from the information signals in amplitude, polarity or frequency or length
• CPC Class Codes: H04Q 11/04 for time-division multiplexing H04Q11/0001 takes precedence
• CPC Class Codes: H04Q 11/0428 Integrated services digital network, i.e. systems for transmission of different types of digitised signals, e.g. speech, data, telecentral, television signals
• CPC Class Codes: H04Q 2213/13098 Mobile subscriber
• CPC Class Codes: H04Q 2213/13202 Network termination [NT]
• CPC Class Codes: H04Q 2213/13204 Protocols
• CPC Class Codes: H04Q 2213/13209 ISDN
• CPC Class Codes: H04Q 2213/13216 Code signals, frame structure
• CPC Class Codes: H04Q 2213/1327 Release and resetting of connection
• CPC Class Codes: H04Q 2213/13298 Local loop systems, access network
• CPC Class Codes: H04Q 2213/13332 Broadband, CATV, dynamic bandwidth allocation
• CPC Class Codes: H04Q 2213/1336 Synchronisation
• CPC Class Codes: H04Q 2213/13389 : LAN, internet
• CPC Class Codes: H04W 28/04 : Error control
• CPC Class Codes: H04W 28/18 : Negotiating wireless communication parameters
• CPC Class Codes: H04W 72/0446 : Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 74/004 : in the uplink, i.e. towards network
• CPC Class Codes: H04W 74/04 : Scheduled access hybrid access H04W74/02
• CPC Class Codes: H04W 74/0833 : Random access procedures, e.g. with 4-step access
• CPC Class Codes: H04W 84/14 : WLL [Wireless Local Loop]; RLL [Radio Local Loop]

Abstract

A communications system improves performance of detecting a signal having an indication of a request to change communications states by making at least two positive identifications of the request in a given time frame. The system may further improve performance by applying a difference in power levels for a non-request state (i.e., steady state or ‘control hold’ state) versus a request state (i.e., ‘request to change’ state). In one particular application, a base station determines a request to change communications states with a reasonably high probability of detection and a reasonably low probability of false detection. The system has a reduced number of erroneous communications states, such as erroneous traffic channel allocations. The detection technique is compatible with 1xEV-DV systems and I-CDMA systems, but general enough to support systems employing various other communications protocols used in wired and wireless communications systems.

Claims

1. A wireless transmit receive unit (WTRU) comprising:

a selector configured to select indications associated with a communication state to include in a signal, wherein the indications are multiplexed in a time slot before being included in the signal;

a transmitter configured to transmit the signal to a base station, wherein the signal includes a maintenance channel, a plurality of traffic channels, an access channel, a heartbeat standby channel, and a heartbeat request active channel; and

a receiver configured to receive at least one allocated traffic channel from the base station when the transmitted signal is a request to transmit data according to predetermined criteria.

2. The WTRU of claim 1 wherein the indications indicate that the WTRU is requesting to transmit data on a traffic channel to the base station.

3. The WTRU of claim 1 wherein the indications indicate that the WTRU is not requesting traffic channels.

4. The WTRU of claim 1 wherein the communication state is a control hold state.

5. The WTRU of claim 1 wherein the communication state is a request to transmit data state.

6. The WTRU of claim 1 wherein the communication state is a data traffic state.

7. The WTRU of claim 1 wherein the predetermined criteria is a power measurement.

8. The WTRU of claim 7 wherein the power measurement is used to determine when signal is a request to transmit data.

9. The WTRU of claim 8 wherein each indication has a different energy level and the difference in power levels is used to determine when the signal is a request to transmit data.

10. The WTRU of claim 1 wherein the predetermined criteria is based on a detection counter and a non-detection counter.

11. The WTRU of claim 10 wherein the detection counter and the non-detection counter are used to determine when the signal is a request to transmit data.

12. The WTRU of claim 11 wherein the detection counter is incremented and compared against a first threshold to determine if the signal is a request to transmit data.

13. The WTRU of claim 11 wherein the non-detection counter is incremented and compared against a second threshold to determine if the signal is a request to transmit data.

14. The WTRU of claim 1 wherein the WTRU is configured for code division multiple access (CDMA) operation.

15. The WTRU of claim 1 wherein the WTRU is configured for orthogonal frequency division multiplexing (OFDM) operation.

16. A base station comprising:

a receiver configured for receive a signal including indications associated with a communication state from a wireless transmit receive unit (WTRU), wherein the signal includes a maintenance channel, a plurality of traffic channels, an access channel, a heartbeat standby channel, and a heartbeat request active channel;

a detection processor, wherein the detection processor comprises

a heartbeat processor configured to process the received heartbeat standby channel and output a heartbeat energy level,

a request channel processor configured to process the received heartbeat request active channel and output a request energy level,

a hypothesis detector configured to receive the heartbeat energy level and the request energy level and determine the signal type of the received signal, and

a state machine configured to receive the output from the hypothesis detector and determine whether the received signal is a request to transmit data using a power measurement of the output received from the hypothesis detector, wherein the heartbeat energy level is compared against a first energy threshold and the request energy level is compared against a second energy threshold to determine if the received signal is a request to transmit data; and

a processor configured to allocate at least one traffic channel to the WTRU when the received signal is a request to transmit data.

17. The base station of claim 16 wherein the energy thresholds are dynamically selected using a feedback loop.

18. The base station of claim 16 wherein the energy thresholds are predetermined.

19. The base station of claim 16 wherein the indications indicate that the WTRU is requesting to transmit data on a traffic channel to the base station.

20. The base station of claim 16 wherein the indications indicate that the WTRU is not requesting traffic channels.

21. The base station of claim 16 wherein the allocating at least one traffic channel to the WTRU only occurs when detecting two or more requests to transmit data.

22. The base station of claim 16 wherein the state machine acts as an interrupt service routine upon receipt of any output from the hypothesis detector.

23. The base station of claim 16 wherein the heartbeat energy level and the requested energy level depend upon the occupancy of time slots in a traffic channel.

24. A base station comprising:

a receiver configured for receive a signal including indications associated with a communication state from a wireless transmit receive unit (WTRU), wherein the signal includes a maintenance channel, a plurality of traffic channels, an access channel, a heartbeat standby channel, and a heartbeat request active channel;

a detection processor, wherein the detection processor comprises

a heartbeat processor configured to process the received heartbeat standby channel and output a heartbeat energy level,

a request channel processor configured to process the received heartbeat request active channel and output a request energy level,

a hypothesis detector configured to receive the heartbeat energy level and the request energy level and determine the signal type of the received signal, and

a state machine configured to receive the output from the hypothesis detector and determine whether the received signal is a request to transmit data using a detection counter and a non-detection counter in the state machine, wherein the detection counter is incremented and compared against a first threshold and the non-detection counter is incremented and compared against a second threshold to determine if the received signal is a request to transmit data from the WTRU; and

a processor configured to allocate at least one traffic channel to the WTRU when the received signal is a request to transmit data.

25. The base station of claim 24 wherein the thresholds are predetermined.

26. The base station of claim 24 wherein the indications indicate that the WTRU is requesting to transmit data on a traffic channel to the base station.

27. The base station of claim 24 wherein the indications indicate that the WTRU is not requesting traffic channels.

28. The base station of claim 24 wherein the allocating at least one traffic channel to the WTRU only occurs when detecting two or more requests to transmit data.

29. The base station of claim 24 wherein the state machine acts as an interrupt service routine upon receipt of any output from the hypothesis detector.

30. A method for use in a wireless transmit receive unit (WTRU), the method comprising:

selecting indications associated with a communication state to include in a signal, wherein the indications are multiplexed in a time slot before being included in the signal;

transmitting the signal to a base station, wherein the signal includes a maintenance channel, a plurality of traffic channels, an access channel, a heartbeat standby channel, and a heartbeat request active channel; and

receiving at least one allocated traffic channel from the base station when the transmitted signal is a request to transmit data according to predetermined criteria.

31. The method of claim 30 wherein the indications indicate that the WTRU is requesting to transmit data on a traffic channel to the base station.

32. The method of claim 30 wherein the indications indicate that the WTRU is not requesting traffic channels.

33. The method of claim 30 wherein the communication state is a control hold state.

34. The method of claim 30 wherein the communication state is a request to transmit data state.

35. The method of claim 30 wherein the communication state is a data traffic state.

36. The method of claim 30 wherein the predetermined criteria is a power measurement.

37. The method of claim 36 wherein the power measurement is used to determine when signal is a request to transmit data.

38. The method of claim 37 wherein each indication has a different energy level and the difference in power levels is used to determine when the signal is a request to transmit data.

39. The method of claim 30 wherein the predetermined criteria is based on a detection counter and a non-detection counter.

40. The method of claim 39 wherein the detection counter and the non-detection counter are used to determine when the signal is a request to transmit data.

41. The method of claim 40 wherein the detection counter is incremented and compared against a first threshold to determine if the signal is a request to transmit data.

42. The method of claim 40 wherein the non-detection counter is incremented and compared against a second threshold to determine if the signal is a request to transmit data.

43. The method of claim 30 wherein the WTRU is configured for code division multiple access (CDMA) operation.

44. The method of claim 30 wherein the WTRU is configured for orthogonal frequency division multiplexing (OFDM) operation.

45. A method for use in a base station, the method comprising:

receiving a signal including indications associated with a communications state from a wireless transmit receive unit (WTRU), wherein the signal includes a maintenance channel, a plurality of traffic channels, an access channel, a heartbeat standby channel, and a heartbeat request active channel;

processing the received heartbeat standby channel and outputting a heartbeat energy level;

processing the received heartbeat request active channel and outputting a request energy level,

determining the signal type of the received signal using the heartbeat energy level and the request energy level;

determining whether the received signal is a request to transmit data using a power measurement of the output received from the hypothesis detector, wherein the heartbeat energy level is compared against a first energy threshold and the request energy level is compared against a second energy threshold to determine if the received signal is a request to transmit data; and

allocating at least one traffic channel to the WTRU when the received signal is a request to transmit data.

46. The method of claim 45 wherein the energy thresholds are dynamically selected using a feedback loop.

47. The method of claim 45 wherein the energy thresholds are predetermined.

48. The method of claim 45 wherein the indications indicate that the WTRU is requesting to transmit data on a traffic channel to the base station.

49. The method of claim 45 wherein the indications indicate that the WTRU is not requesting traffic channels.

50. The method of claim 45 wherein the allocating at least one traffic channel to the WTRU only occurs when detecting two or more requests to transmit data.

51. The method of claim 45 wherein the state machine acts as an interrupt service routine upon receipt of any output from the hypothesis detector.

52. The method of claim 45 wherein the heartbeat energy level and the requested energy level depend upon the occupancy of time slots in a traffic channel.

53. A method for use in a base station, the method comprising:

receiving a signal including indications associated with a communications state from a wireless transmit receive unit (WTRU), wherein the signal includes a maintenance channel, a plurality of traffic channels, an access channel, a heartbeat standby channel, and a heartbeat request active channel;

processing the received heartbeat standby channel and outputting a heartbeat energy level;

processing the received heartbeat request active channel and outputting a request energy level,

determining the signal type of the received signal using the heartbeat energy level and the request energy level;

determining whether the received signal is a request to transmit data using a detection counter and a non-detection counter in the state machine, wherein the detection counter is incremented and compared against a first threshold and the non-detection counter is incremented and compared against a second threshold to determine if the received signal is a request to transmit data from the WTRU; and

allocating at least one traffic channel to the WTRU when the received signal is a request to transmit data.

54. The method of claim 53 wherein the thresholds are predetermined.

55. The method of claim 53 wherein the indications indicate that the WTRU is requesting to transmit data on a traffic channel to the base station.

56. The method of claim 53 wherein the indications indicate that the WTRU is not requesting traffic channels.

57. The method of claim 53 wherein the allocating at least one traffic channel to the WTRU only occurs when detecting two or more requests to transmit data.

58. The method of claim 53 wherein the state machine acts as an interrupt service routine upon receipt of any output from the hypothesis detector.