Mode switching in adaptive array communications systems

• US 6,564,036 B1
• Filed: 09/29/2000
• Issued: 05/13/2003
• Est. Priority Date: 09/29/2000
• Status: Expired due to Term

• Current Assignee: Intel Corporation
• Original Assignee: ArrayComm LLC (Ygomi LLC)
• Inventors: Kasapi, Athanasios A.
• Primary Examiner(s): Le, Thanh Cong
• Assistant Examiner(s): LE, LANA N
• Application Number:
  US09/676,886
• Time in Patent Office: 956 Days
• Field of Search: 455/562, 455/561, 455/67.1, 455/67.3, 455/1, 455/63
• US Class Current: 455/1
• CPC Class Codes: H04W 16/28 using beam steering

Abstract

A method and system for providing selective interference mitigation (or nulling) in an adaptive array system. A communication device, typically employing an adaptive array, determines an indication of signal reception quality for a first remote user terminal in communication with the communication device. The communication device provides a first mode of operation wherein a first amount of nulling with respect to at least one interfering source is generated by the communication device. In addition, the communication device provides a second mode of operation characterized by generating a second amount of nulling with respect to the at least one interfering source, wherein the second amount of nulling is relatively greater than the first amount of nulling. Based on the relative signal reception quality indication, the communication device selects one of the first and second modes of operation.

Claims

1. In a wireless communication system, a method comprising:

obtainng an indication of signal reception quality for a first remote user terminal in communication with a communication device employing an antenna array;

providing a first mode of operation for said communication device, said first mode of operation generating a first amount of nulling with respect to at least one interfering source;

providing a second mode of operation for said communication device, said second mode of operation characterized by providing a second amount of nulling with respect to said at least one interfering source, wherein said second amount of nulling is relatively greater than said first amount of nulling; and

based on said indication, said communication operating in one of said first and said second modes.

2. The method of claim 1, wherein said amount of nulling is defined by the quantity of nulls generated by said communication device, such that the quantity of nulls generated in said second mode of operation is greater than the quantity of nulls generated in said first mode of operation.

3. The method of claim 1, wherein said amount of nulling is defined by the intensity of at least one null generated by said communication device, such that the intensity of at least one null generated in said second mode of operation is greater intensity of at least one null generated in said second mode of operation is greater than the intensity of said at least one null generated in said first mode of operation.

4. The method of claim 1, wherein said amount of nulling is defined both by the number of nulls generated in each of said first and second modes of operation and the intensity of at least one null generated in said first and second modes of operation.

5. The method of claim 1, wherein said indication is defined by a relative signal strength of a downlink signal transmitted by said communication device to said first remote user terminal, said relative signal strength measured by said first remote user terminal.

6. The method of claim 5, further comprising:

said first remote user terminal providing said indication to said communication device as information contained in an uplink signal.

7. The method of claim 1, wherein said indication is defined by a relative signal strength of an uplink signal transmitted by said first remote user terminal to said communication device, said relative signal strength measured by said communication device.

8. The method of claim 1, wherein said first interfering source comprises a second remote user terminal in communication with said communication device.

9. The method of claim 8, further comprising:

said first and second remote user terminals simultaneously sharing a communication channel comprising a carrier frequency.

10. The method of claim 8, further comprising:

said first and second remote user terminals simultaneously using adjacent channels of communication.

11. The method of claim 1, wherein said first interfering source comprises a second remote user terminal, said communication device comprising a first base station coupled to a communication network, said second remote user terminal in communication with a second base station coupled to said network.

12. The method of claim 11, further comprising:

said first and second remote user terminals simultaneously sharing a communication channel comprising a carrier frequency.

13. The method of claim 1, further comprising:

determining said indication at a predetermined time interval.

14. The method of claim 1, further comprising:

said communication device determining said indication upon said communication receiving an uplink signal from said first remote user terminal.

15. The method of claim 1, further comprising:

said first remote user terminal receiving a plurality of downlink signals from said communication device; and

said first remote user terminal transmitting said indication to said communication device for each of said plurality of downlink signals.

16. A communication device, comprising:

an antenna array to transfer uplink signals and downlink signals with a first remote user terminal in communication with the communication device, and to null at least one interfering source;

a processor, coupled to the antenna array, to process the uplink and downlink signals transferred between the first remote user terminal and the communication device; and

a selector, coupled to the processor, to select a first mode of operation for said communication device when reception quality of said first remote user terminal is below a threshold, and to select a second mode of operation for said communication device when reception quality of said first remote user terminal is above the threshold, the second mode of operation characterized by providing an increased amount of nulling toward the interfering source relative to the amount of nulling directed toward the interfering source in the first mode of operation.

17. The communication device of claim 16, further comprising a signal quality measurement unit to determine the reception quality for the first remote user terminal as a function of a measured strength of an uplink signal received by the antenna array from the first remote user terminal.

18. The communication device of claim 16, wherein the first remote user terminal comprises a signal quality measurement unit to determine the reception quality of a downlink signal received by the first remote user terminal from the communication device.

19. The communication device of claim 16, wherein the amount of nulling is defined by the number of nulls generated by the communication device in the first and second modes of operation, such that the number of null generated by the communication device in the second mode of operation exceeds the number of nulls generated by the communication device in the first mode of operation.

20. The communication device of claim 16, wherein the amount of nulling is defined by the intensity of at least one null generated by the communication device in the first and second modes of operation, such that the intensity of the at least one null generated by the communication device is greater exceeds the intensity of the at least one null generated by the communication device in the first mode of operation.

21. The communication device of claim 16, wherein interfering source comprises a second remote user terminal occupying a channel that causes interference to communication between the first remote user terminal and the second remote user terminal.

22. A machine-readable medium having store thereon a machine-executable instructions, that, when processed by a machine, cause the machine to perform a method comprising:

determining an indication of signal reception quality for a first remote user terminal in communication with a communication device employing an antenna array;

providing a first mode of operation for said communication device, said first mode of operation generating a first amount of nulling with respect to at least one interfering source;

providing a second mode of operation for said communication device, said second mode of operation characterized by providing a second amount of nulling with respect to said at least one interfering source, wherein said second amount of nulling is relatively greater than said first amount of nulling; and

based on said relative signal reception quality indication, said communication device selecting one of said first and said second modes of operation.

23. The machine-readable medium of claim 22, wherein said amount of nulling is defined by the quantity of nulls generated by said communication device, such that the quantity of nulls generated in said second mode of operation is greater than the quantity of nulls generated in said first mode of operation.

24. The machine-readable medium of claim 22, wherein said amount of nulling is defined by the intensity of at least one null generated by said communication device, such that the intensity of at least one null generated in said second mode of operation is greater than the intensity of said at least one null generated in said first mode of operation.

25. The machine-readable medium of claim 22, wherein said amount of nulling is defined both by the number of nulls generated in each of said first and second modes of operation and the intensity of at least one null generated in said first and second modes of operation.

26. The machine-readable medium of claim 22, wherein said indication is defined by a relative signal strength of a downlink signal transmitted by said communication device to said first remote user terminal, said relative signal strength measured by said first remote user terminal.

27. The machine-readable medium of claim 26, said method further comprising:

said first remote user terminal providing said indication to said communication device as information contained in an uplink signal.

28. The machine-readable medium of claim 22, wherein said indication is defined by a relative signal strength of an uplink signal transmitted by said first remote user terminal to said communication device, said relative signal strength measured by said communication device.

29. The machine-readable medium of claim 22, wherein said first interfering source comprises a second remote user terminal in communication with said communication device.

30. The machine-readable medium of claim 29, said method further comprising:

said first and second remote user terminals simultaneously sharing a communication channel comprising a carrier frequency.

31. The machine-readable medium of claim 29, said method further comprising:

said first and second remote user terminals simultaneously using adjacent channels of communication.

32. The method of claim 22, wherein said first interfering source comprises a second remote user terminal, said communication device comprising a first base station coupled to a communication network, said second remote user terminal in communication with a second base station coupled to said network.

33. The machine-readable medium of claim 32, said method further comprising:

said first and second remote user terminals simultaneously sharing a communication channel comprising a carrier frequency.

34. The machine-readable medium of claim 22, said method further comprising:

determining said indication at a predetermined time interval.

35. The machine-readable medium of claim 22, said method further comprising:

said communication device determining said indication upon said communication receiving an uplink signal from said first remote user terminal.

36. The machine-readable medium of claim 22, said method further comprising:

said first remote user terminal receiving a plurality of downlink signals from said communication device; and

said first remote user terminal transmitting said indication to said communication device for each of said plurality of downlink signals.