UMB CELL SITE MODEM ARCHITECTURE AND METHODS

• US 20090161655A1
• Filed: 12/19/2008
• Published: 06/25/2009
• Est. Priority Date: 12/20/2007
• Status: Abandoned Application

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Uppala, Sathyadev Venkata
• Application Number:
  US12/340,441
• Publication Number:
  US 20090161655A1
• Time in Patent Office: Days
• US Class Current: 370/350
• CPC Class Codes: H04J 3/0682 by delay compensation, e.g. by compensation of propagation delay or variations thereof, by ranging
• CPC Class Codes: H04J 3/0697 Synchronisation in a packet node
• CPC Class Codes: H04W 56/00 Synchronisation arrangements

Abstract

An apparatus and method for sample synchronization comprising receiving a return link (RL) timestamp from a radio frequency front end (RFFE); receiving a system time second from a navigation and timing system; generating a forward link (FL) timestamp based on the RL timestamp and the system time second; and including the FL timestamp and the system time second in a time data. In one aspect, the apparatus and method is used for RF control comprising storing gain information and gating control information in a memory; and performing one or more of the following: sending a first desired timestamp and the gain information to a radio frequency front end (RFFE); sending a second desired timestamp and a txEnable command to a transmit gating control; or sending a third desired timestamp and a rxEnable command to a receive gating control.

Claims

1. A method for sample synchronization comprising:

receiving a return link (RL) timestamp from a radio frequency front end (RFFE);

receiving a system time second from a navigation and timing system;

generating a forward link (FL) timestamp based on the RL timestamp and the system time second; and

including the FL timestamp and the system time second in a time data.

2. The method of claim 1 further comprising multiplexing the time data into a sample stream.

3. The method of claim 2 further comprising sending the sample stream.

4. The method of claim 1 wherein the navigation and timing system is one of Global Navigation Satellite System (GNSS), Russian GLONASS (Global Navigation Satellite System), The European Union'"'"'s Galileo positioning system, The Indian Regional Navigational Satellite System (IRNSS) or China'"'"'s Beidou Satellite Navigation and Positioning System.

5. The method of claim 1 wherein the navigation and timing system is a Global Positioning System (GPS).

6. The method of claim 5 further comprising aligning the system time second to a GPS time of the Global Positioning System.

7. The method of claim 1 further comprising aligning a timestamp counter to the system time second.

8. The method of claim 1 wherein the FL timestamp is written every 1024 samples for a 10 MHz bandwidth UMB frequency division duplex (FDD) mode.

9. The method of claim 2 wherein the FL timestamp further includes information of the current mode of operation represented by the sample stream.

29. The cell site modem of claim 2 wherein the FL timestamp further includes information of the current mode of operation represented by the sample stream.

10. A method for RF control comprising:

storing gain information and gating control information in a memory; and

performing one of the following;

a) sending a first desired timestamp and the gain information to a radio frequency front end (RFFE);

b) sending a second desired timestamp and a txEnable command to a transmit gating control;

or

c) sending a third desired timestamp and a rxEnable command to a receive gating control.

11. The method of claim 10 further comprising receiving the gain information and gating control information.

12. The method of claim 10 wherein the transmit gating control and the receive gating control are part of the radio frequency front end (RFFE).

13. The method of claim 10 further comprising performing a second of the following not already performed:

a) sending the first desired timestamp and the gain information to the radio frequency front end (RFFE);

b) sending the second desired timestamp and a txEnable command to the transmit gating control;

or

c) sending the third desired timestamp and a rxEnable command to the receive gating control.

14. The method of claim 13 further comprising performing the last of the following not already performed:

a) sending the first desired timestamp and the gain information to the radio frequency front end (RFFE);

b) sending the second desired timestamp and a txEnable command to the transmit gating control;

or

c) sending the third desired timestamp and a rxEnable command to the receive gating control.

15. The method of claim 14 wherein the transmit gating control and the receive gating control are part of the radio frequency front end (RFFE).

16. The method of claim 10 wherein a gain of the radio frequency front end (RFFE) is changed to within +/−

2 μ

sec of a desired time based on the gain information.

17. The method of claim 16 wherein the desired time is the time at which gain change takes effect.

18. The method of claim 10 further comprising multiplexing at least one of the following:

first desired timestamp, second desired timestamp, third desired timestamp, gain information, txEnable command or rxEnable command into a sample stream.

19. The method of claim 18 wherein the gain information (rxGain) is defined by

rxGain=round((Pout−

Pin)*2),

wherein Pin is an estimate of the receive power at an antenna port and Pout is given by;

Pout=10 log(σ

²)

wherein σ

² is the mean squared digital value of the sample stream.

20. The method of claim 19 wherein the gain information (rxGain) represents a desired gain in 0.5 dB steps.

21. A cell site modem (CSM) for sample synchronization comprising a processor and circuitry configured to:

receive a return link (RL) timestamp from a radio frequency front end (RFFE);

receive a system time second from a navigation and timing system;

generate a forward link (FL) timestamp based on the RL timestamp and the system time second; and

include the FL timestamp and the system time second in a time data.

22. The cell site modem of claim 21 wherein the processor and circuitry are further configured to multiplex the time data into a sample stream.

23. The cell site modem of claim 22 wherein the processor and circuitry are further configured to send the sample stream.

24. The cell site modem of claim 21 wherein the navigation and timing system is one of Global Navigation Satellite System (GNSS), Russian GLONASS (Global Navigation Satellite System), The European Union'"'"'s Galileo positioning system, The Indian Regional Navigational Satellite System (IRNSS) or China'"'"'s Beidou Satellite Navigation and Positioning System.

25. The cell site modem of claim 21 wherein the navigation and timing system is a Global Positioning System (GPS).

26. The cell site modem of claim 25 wherein the processor and circuitry are further configured to align the system time second to a GPS time of the Global Positioning System.

27. The cell site modem of claim 21 wherein the processor and circuitry are further configured to align a timestamp counter to the system time second.

28. The cell site modem of claim 21 wherein the FL timestamp is written every 1024 samples for a 10 MHz bandwidth UMB frequency division duplex (FDD) mode.

30. A cell site modem (CSM) for RF control comprising a processor and circuitry configured to:

store gain information and gating control information in a memory; and

perform one of the following;

a) send a first desired timestamp and the gain information to a radio frequency front end (RFFE);

b) send a second desired timestamp and a txEnable command to a transmit gating control;

or

c) send a third desired timestamp and a rxEnable command to a receive gating control.

31. The cell site modem of claim 30 wherein the processor and circuitry are further configured to receive the gain information and gating control information.

32. The cell site modem of claim 30 wherein the transmit gating control and the receive gating control are part of the radio frequency front end (RFFE).

33. The cell site modem of claim 30 wherein the processor and circuitry are further configured to perform a second of the following not already performed:

a) send the first desired timestamp and the gain information to the radio frequency front end (RFFE);

b) send the second desired timestamp and a txEnable command to the transmit gating control;

or

c) send the third desired timestamp and a rxEnable command to the receive gating control.

34. The cell site modem of claim 33 wherein the processor and circuitry are further configured to perform the last of the following not already performed:

a) send the first desired timestamp and the gain information to the radio frequency front end (RFFE);

b) send the second desired timestamp and a txEnable command to the transmit gating control;

or

c) send the third desired timestamp and a rxEnable command to the receive gating control.

35. The cell site modem of claim 34 wherein the transmit gating control and the receive gating control are part of the radio frequency front end (RFFE).

36. The cell site modem of claim 30 wherein a gain of the radio frequency front end (RFFE) is changed to within +/−

2 μ

sec of a desired time based on the gain information.

37. The cell site modem of claim 36 wherein the desired time is the time at which gain change takes effect.

38. The cell site modem of claim 30 wherein the processor and circuitry are further configured to multiplex at least one of the following:

first desired timestamp, second desired timestamp, third desired timestamp, gain information, txEnable command or rxEnable command into a sample stream.

39. The cell site modem of claim 38 wherein the gain information (rxGain) is defined by

rxGain=round((Pout−

Pin)*2),

wherein Pin is an estimate of the receive power at an antenna port and Pout is given by;

Pout=10 log(σ

²)

wherein σ

² is the mean squared digital value of the sample stream.

40. The cell site modem of claim 39 wherein the gain information (rxGain) represents a desired gain in 0.5 dB steps.

41. A device for sample synchronization comprising:

means for receiving a return link (RL) timestamp from a radio frequency front end (RFFE);

means for receiving a system time second from a navigation and timing system;

means for generating a forward link (FL) timestamp based on the RL timestamp and the system time second; and

means for including the FL timestamp and the system time second in a time data.

42. The device of claim 41 further comprising means for multiplexing the time data into a sample stream.

43. The device of claim 42 further comprising means for sending the sample stream.

44. The device of claim 41 wherein the navigation and timing system is one of Global Navigation Satellite System (GNSS), Russian GLONASS (Global Navigation Satellite System), The European Union'"'"'s Galileo positioning system, The Indian Regional Navigational Satellite System (IRNSS) or China'"'"'s Beidou Satellite Navigation and Positioning System.

45. The device of claim 41 wherein the navigation and timing system is a Global Positioning System (GPS).

46. The device of claim 45 further comprising means for aligning the system time second to a GPS time of the Global Positioning System.

47. The device of claim 41 further comprising means for aligning a timestamp counter to the system time second.

48. The device of claim 41 wherein the FL timestamp is written every 1024 samples for a 10 MHz bandwidth UMB frequency division duplex (FDD) mode.

49. The device of claim 42 wherein the FL timestamp further includes information of the current mode of operation represented by the sample stream.

50. A device for RF control comprising:

means for storing gain information and gating control information in a memory; and

means for performing one of the following;

a) sending a first desired timestamp and the gain information to a radio frequency front end (RFFE);

b) sending a second desired timestamp and a txEnable command to a transmit gating control;

or

c) sending a third desired timestamp and a rxEnable command to a receive gating control.

51. The device of claim 50 further comprising means for receiving the gain information and gating control information.

52. The device of claim 50 wherein the transmit gating control and the receive gating control are part of the radio frequency front end (RFFE).

53. The device of claim 50 further comprising means for performing a second of the following not already performed:

a) sending the first desired timestamp and the gain information to the radio frequency front end (RFFE);

b) sending the second desired timestamp and a txEnable command to the transmit gating control;

or

c) sending the third desired timestamp and a rxEnable command to the receive gating control.

54. The device of claim 53 further comprising means for performing the last of the following not already performed:

a) sending the first desired timestamp and the gain information to the radio frequency front end (RFFE);

b) sending the second desired timestamp and a txEnable command to the transmit gating control;

or

c) sending the third desired timestamp and a rxEnable command to the receive gating control.

55. The device of claim 54 wherein the transmit gating control and the receive gating control are part of the radio frequency front end (RFFE).

56. The device of claim 50 wherein a gain of the radio frequency front end (RFFE) is changed to within +/−

2 μ

sec of a desired time based on the gain information.

57. The device of claim 56 wherein the desired time is the time at which gain change takes effect.

58. The device of claim 50 further comprising means for multiplexing at least one of the following:

first desired timestamp, second desired timestamp, third desired timestamp, gain information, txEnable command or rxEnable command into a sample stream.

59. The device of claim 58 wherein the gain information (rxGain) is defined by

rxGain=round((Pout−

Pin)*2),

wherein Pin is an estimate of the receive power at an antenna port and Pout is given by;

Pout=10 log(σ

²)

wherein σ

² is the mean squared digital value of the sample stream.

60. The device of claim 59 wherein the gain information (rxGain) represents a desired gain in 0.5 dB steps.

61. A computer-readable medium including program code stored thereon, comprising:

program code for receiving a return link (RL) timestamp from a radio frequency front end (RFFE);

program code for receiving a system time second from a navigation and timing system;

program code for generating a forward link (FL) timestamp based on the RL timestamp and the system time second; and

program code for including the FL timestamp and the system time second in a time data.

62. The computer-readable medium of claim 61 further comprising program code for multiplexing the time data into a sample stream.

63. The computer-readable medium of claim 62 further comprising program code for sending the sample stream.

64. The computer-readable medium of claim 61 wherein the navigation and timing system is one of Global Navigation Satellite System (GNSS), Russian GLONASS (Global Navigation Satellite System), The European Union'"'"'s Galileo positioning system, The Indian Regional Navigational Satellite System (IRNSS) or China'"'"'s Beidou Satellite Navigation and Positioning System.

65. The computer-readable medium of claim 61 wherein the navigation and timing system is a Global Positioning System (GPS).

66. The computer-readable medium of claim 65 further comprising program code for aligning the system time second to a GPS time of the Global Positioning System.

67. The computer-readable medium of claim 61 further comprising program code for aligning a timestamp counter to the system time second.

68. The computer-readable medium of claim 61 wherein the FL timestamp is written every 1024 samples for a 10 MHz bandwidth UMB frequency division duplex (FDD) mode.

69. The computer-readable medium of claim 62 wherein the FL timestamp further includes information of the current mode of operation represented by the sample stream.

70. A computer-readable medium including program code stored thereon, comprising:

program code for storing gain information and gating control information in a memory; and

program code for performing one of the following;

a) sending a first desired timestamp and the gain information to a radio frequency front end (RFFE);

b) sending a second desired timestamp and a txEnable command to a transmit gating control;

or

c) sending a third desired timestamp and a rxEnable command to a receive gating control.

71. The computer-readable medium of claim 70 further comprising program code for receiving the gain information and gating control information.

72. The computer-readable medium of claim 70 wherein the transmit gating control and the receive gating control are part of the radio frequency front end (RFFE).

73. The computer-readable medium of claim 70 further comprising program code for performing a second of the following not already performed:

a) sending the first desired timestamp and the gain information to the radio frequency front end (RFFE);

b) sending the second desired timestamp and a txEnable command to the transmit gating control;

or

c) sending the third desired timestamp and a rxEnable command to the receive gating control.

74. The computer-readable medium of claim 73 further comprising program code for performing the last of the following not already performed:

a) sending the first desired timestamp and the gain information to the radio frequency front end (RFFE);

b) sending the second desired timestamp and a txEnable command to the transmit gating control;

or

c) sending the third desired timestamp and a rxEnable command to the receive gating control.

75. The computer-readable medium of claim 74 wherein the transmit gating control and the receive gating control are part of the radio frequency front end (RFFE).

76. The computer-readable medium of claim 70 wherein a gain of the radio frequency front end (RFFE) is changed to within +/−

2 μ

sec of a desired time based on the gain information.

77. The computer-readable medium of claim 76 wherein the desired time is the time at which gain change takes effect.

78. The computer-readable medium of claim 70 further comprising program code for multiplexing at least one of the following:

first desired timestamp, second desired timestamp, third desired timestamp, gain information, txEnable command or rxEnable command into a sample stream.

79. The computer-readable medium of claim 78 wherein the gain information (rxGain) is defined by

rxGain=round((Pout−

Pin)*2),

wherein Pin is an estimate of the receive power at an antenna port and Pout is given by;

Pout=10 log(σ

²)

wherein σ

² is the mean squared digital value of the sample stream.

80. The computer-readable medium of claim 79 wherein the gain information (rxGain) represents a desired gain in 0.5 dB steps.