Antenna adaptation comparison method for high mobility

• US 7,227,907 B2
• Filed: 03/10/2003
• Issued: 06/05/2007
• Est. Priority Date: 03/08/2002
• Status: Expired due to Fees

• Current Assignee: IPR Licensing Incorporated (InterDigital, Inc.)
• Original Assignee: IPR Licensing Incorporated (InterDigital, Inc.)
• Inventors: Proctor, Jr., James A., Amalfitano, Carlo, Ryu, Kil H.
• Primary Examiner(s): PHU, PHUONG M
• Application Number:
  US10/386,364
• Publication Number:
  US 20040009794A1
• Time in Patent Office: 1,548 Days
• Field of Search: 375/295, 375/296, 455/575.7, 455/562.1, 342/372, 342/373, 342/368, 343/834, 343/835, 370/347
• US Class Current: 375/296
• CPC Class Codes: H01Q 19/32 the primary active element being end-fed and elongated
• CPC Class Codes: H01Q 3/44 varying the electric or magnetic characteristics of reflecting, refracting, or diffracting devices associated with the radiating element
• CPC Class Codes: H04W 16/28 using beam steering

Abstract

A system causes a scan angle of a directional antenna to change temporarily from a current scan angle to at least one trial scan angle during reception of predetermined portions of an information carrying signal. At the trial scan angle(s), a trial metric associated with each trial scan angle is determined by the system. The system then selects a next scan angle based on the trial metrics. Examples of predetermined portions of the information carrying signal include the Power Control Bit (PCB) and certain symbol periods of the Forward Error Correction (FEC) block.

Claims

1. A method for making measurements to use in the adaptation of a directional antenna, the method comprising:

causing a scan angle of the antenna to change temporarily from a current

scan angle to at least one trial scan angle during reception of a Power Control Bit (PCB) with a dwell time that minimizes an impact to a forward link power control loop;

determining a trial metric associated with each trial scan angle; and

selecting a next scan angle based on the trial metrics.

2. The method according to claim 1 wherein the Power Control Bit with the dwell time that minimizes the impact to the forward link power control loop is selected to minimize degradation of an information carrying signal.

3. The method according to claim 1 wherein the dwell time of the Power Control Bit is less than the duration of a single power control command generation period.

4. The method according to claim 1 wherein the Power Control Bit (PCB) is during at least one of the following:

reception of the Power Control Bit (PCB);

low information transfer;

receipt of one or more Forward Error Correction (FEC) bits in an FEC block;

a time when no traffic channel is assigned;

or

a time when no payload is assigned.

5. The method according to claim 1 wherein the trial metrics are a function of at least one of the following:

the pilot signal of a forward link of a CDMA system;

parameters of a control channel;

parameters of an assigned traffic channel;

or

parameters of any forward link channel.

6. The method according to claim 1 further including determining a current metric associated with a current scan angle of the antenna;

and selecting a next scan angle includes comparing a subset of trial metrics with the current metric.

7. The method according to claim 1 further including:

determining multiple trial metrics for the trial scan angles; and

selecting a next scan angle takes the multiple trial metrics into account.

8. The method according to claim 7 further including averaging or accumulating the multiple trial metrics.

9. The method according to claim 1 further including utilizing information from the forward link to determine the quality of the current scan angle for Time Division Duplex (TDD) systems.

10. The method according to claim 1 further including:

transmitting a signal at each trial scan angle and receiving a metric corresponding thereto from a base station; and

using the received metrics for selecting a next scan angle in a reverse path.

11. The method according to claim 10 used in a Frequency Division Duplex (FDD) or Time Division Duplex (TDD) system.

12. The method according to claim 1 used in a TDD system, wherein at each trial scan angle, the method further includes:

transmitting a signal to a base station; and

wherein determining a trial metric includes receiving the trial metric from the base station.

13. The method according to claim 1 further including determining a received channel parameter and changing a trial scan parameter based on the received channel parameter.

15. The method according to claim 13 wherein the received channel parameter includes at least one of the following:

pilot quality metric, received signal strength, SNR, Ec/Io, Eb/No, variance in signal power, change in pilot phase, or statistical measure of any one or combination of the above.

19. The method according to claim 1 used in a field unit, base station, or access terminal.

14. A method for making measurements to use in the adaptation of a directional antenna, the method comprising:

causing a scan angle of the antenna to change temporarily from a current scan angle to at least one trial scan angle during reception of a predetermined portion of an information carrying signal;

determining a trial metric associated with each trial scan angle;

selecting a next scan angle based on the trial metrics;

determining a received channel parameter and changing a trial scan parameter based on the received channel parameter, the trial scan parameter including a scanning rate or adaptation rate.

16. A method for making measurements to use in the adaptation of a directional antenna, the method comprising:

causing a scan angle of the antenna to change temporarily from a current scan angle to at least one trial scan angle during reception of a predetermined portion of an information carrying signal;

determining a trial metric associated with each trial scan angle;

selecting a next scan angle based on the trial metrics;

determining a received channel parameter and changing a trial scan parameter based on the received channel parameter, the received channel parameter being an Automatic Gain Control (AGC) level crossing rate or variance.

17. A method for making measurements to use in the adaptation of a directional antenna, the method comprising:

causing a scan angle of the antenna to change temporarily from a current scan angle to at least one trial scan angle during reception of a predetermined portion of an information carrying signal;

determining a trial metric associated with each trial scan angle;

selecting a next scan angle based on the trial metrics;

determining a received channel parameter and changing a trial scan parameter based on the received channel parameter, the received channel parameter being based on pilot channel received parameters including at least one of the following;

level crossing rate of an envelope of a correlated pilot signal, variance of the envelope of the correlated pilot signal, statistical function of the envelope of the correlated pilot signal, slew rate of the code phase of the pilot signal, phase of the pilot signal, variance of the pilot signal, or rate of change of the pilot signal.

18. A method for making measurements to use in the adaptation of a directional antenna, the method comprising:

causing a scan angle of the antenna to change temporarily from a current scan angle to at least one trial scan angle during reception of a predetermined portion of an information carrying signal;

determining a trial metric associated with each trial scan angle;

selecting a next scan angle based on the trial metrics;

detecting when direction selection is non-beneficial; and

setting the adaptive antenna into an omni-directional mode.

20. An apparatus for making measurements to use in the adaptation of a directional antenna, the apparatus comprising:

a scan controller to cause a scan angle of the directional antenna to change temporarily from a current scan angle to at least one trial scan angle during reception of a Power Control Bit (PCB) with a dwell time that minimizes an impact to a forward link power control loop;

a processor coupled to the scan controller to determine a trial metric associated with each trial scan angle; and

a selection unit coupled to the processor to select a next scan angle based on the trial metrics.

21. The apparatus according to claim 20 wherein the Power Control Bit (PCB) is selected to minimize degradation of an information carrying signal.

22. The apparatus according to claim 20 wherein the dwell time of the Power Control Bit is less than the duration of a single power control command generation period.

23. The apparatus according to claim 20 wherein the Power Control Bit (PCB) is during at least one of the following:

reception of the Power Control Bit (PCB);

low information transfer;

receipt of one or more Forward Error Correction (FEC) bits in an FEC block;

a time when no traffic channel is assigned;

or

a time when no payload is assigned.

24. The apparatus according to claim 20 wherein the metrics are a function of at least one of the following:

the pilot signal of a forward link of a CDMA system;

parameters of a control channel;

parameters of an assigned traffic channel;

or

parameters of any forward link channel.

25. The apparatus according to claim 20 wherein the processor determines a current metric associated with a current scan angle of the directional antenna and the selection unit selects a next scan angle by comparing a subset of trial metrics with the current metric.

26. The apparatus according to claim 20 wherein the processor determines multiple trial metrics for the trial scan angles and the selection unit selects a next scan angle by taking the multiple trial metrics into account.

27. The apparatus according to claim 26 wherein the processor includes an arithmetic unit to average or accumulate the multiple trial metrics.

28. The apparatus according to claim 20 wherein the processor uses the selected scan angle to determine the quality of the scan angle for Time Division Duplex (TDD) systems.

29. The apparatus according to claim 20 further including

a transceiver to transmit a signal at each trial angle and receive a metric corresponding thereto from a base station;

and

wherein the processor coupled to the transceiver uses the received metrics for selecting a next scan angle in a reverse path.

30. An apparatus according to claim 20 used in a Frequency Division Duplex (FDD) or Time Division Duplex (TDD) system.

31. The apparatus according to claim 20 used in a TDD system, wherein at each trial scan angle, the processor transmits a signal to a base station and responsively receives the trial metric from the base station.

32. The apparatus according to claim 20 wherein the processor receives a channel parameter and changes a trial scan parameter based on the received channel parameter.

34. The apparatus according to claim 32 wherein the received channel parameter includes at least one of the following:

pilot quality metric, received signal strength, SNR, Ec/Io, Eb/No, variance in signal power, change in pilot phase, or statistical measure of any one or combination of the above.

38. The apparatus according to claim 20 used in a field unit, base station, or access terminal.

33. An apparatus for making measurements to use in the adaptation of a directional antenna, the apparatus comprising:

a scan controller to cause a scan angle of the directional antenna to change temporarily from a current scan angle to at least one trial scan angle during reception of a predetermined portion of an information carrying signal;

a processor coupled to the scan controller to determine a trial metric associated with each trial scan angle; and

a selection unit coupled to the processor to select a next scan angle based on the trial metrics, the processor receiving a channel parameter and changing a trial scan parameter based on the received channel parameter, the trial scan parameter including a scanning rate or adaptation rate.

35. An apparatus for making measurements to use in the adaptation of a directional antenna, the apparatus comprising:

a scan controller to cause a scan angle of the directional antenna to change temporarily from a current scan angle to at least one trial scan angle during reception of a predetermined portion of an information carrying signal;

a processor coupled to the scan controller to determine a trial metric associated with each trial scan angle; and

a selection unit coupled to the processor to select a next scan angle based on the trial metrics, the processor receiving a channel parameter and changing a trial scan parameter based on the received channel parameter, the received channel parameter being an Automatic Gain Control (AGC) level crossing rate or variance.

36. An apparatus for making measurements to use in the adaptation of a directional antenna, the apparatus comprising:

a scan controller to cause a scan angle of the directional antenna to change temporarily from a current scan angle to at least one trial scan angle during reception of a predetermined portion of an information carrying signal;

a processor coupled to the scan controller to determine a trial metric associated with each trial scan angle; and

a selection unit coupled to the processor to select a next scan angle based on the trial metrics, the processor receiving a channel parameter and changing a trial scan parameter based on the received channel parameter, the received channel parameter being based on pilot channel received parameters including at least one of the following;

level crossing rate of an envelope of a correlated pilot signal, variance of the envelope of the correlated pilot signal, statistical function of the envelope of the correlated pilot signal, slew rate of the code phase of the pilot signal, phase of the pilot signal, variance of the pilot signal, or rate of change of the pilot signal.

37. An apparatus for making measurements to use in the adaptation of a directional antenna, the apparatus comprising:

a scan controller to cause a scan angle of the directional antenna to change temporarily from a current scan angle to at least one trial scan angle during reception of a predetermined portion of an information carrying signal;

a processor coupled to the scan controller to determine a trial metric associated with each trial scan angle; and

a selection unit coupled to the processor to select a next scan angle based on the trial metrics, the processor receiving a channel parameter and changing a trial scan parameter based on the received channel parameter, the processor is configured to (i) determine when direction selection is non-beneficial and (ii) cause the adaptive antenna to enter into an omni-directional mode.

39. A method for making measurements to use in the adaptation of a directional antenna, the method comprising:

causing a scan angle of the antenna to change temporarily from the current angle to at least one trial scan angle during reception of a Power Control Bit (PCB) with a dwell time that is a fraction of a power control group period;

determining a trial metric associated with each trial scan angle; and

selecting a next scan angle based on the trial metrics.

40. An apparatus for making measurements to use in the adaptation of a directional antenna, the apparatus comprising:

a scan controller to cause a scan angle of the antenna to change temporarily from the current angle to at least one trial scan angle during reception of a Power Control Bit (PCB) with a dwell time that is a fraction of a power control group period;

a processor coupled to the scan controller to determine a trial metric associated with each trial scan angle; and

a selection unit coupled to the processor to select a next scan angle based on the trial metrics.