Network listen with self interference cancellation

• US 9,237,530 B2
• Filed: 11/09/2012
• Issued: 01/12/2016
• Est. Priority Date: 11/09/2012
• Status: Expired due to Fees

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Song, Bongyong, Chakraborty, Kaushik, Soliman, Samir Salib
• Primary Examiner(s): Cumming, William D
• Application Number:
  US13/673,946
• Publication Number:
  US 20140134997A1
• Time in Patent Office: 1,159 Days
• Field of Search: 455/422.1, 455/522, 375/296, 370/320, 370/321, 370/342, 370/350, 370/441, 370/479
• US Class Current: 1/1
• CPC Class Codes: H04W 52/244 Interferences in heterogeneous networks, e.g. among macro and femto or pico cells or other sector / system interference [OSI]

Abstract

A method for wireless communications includes reducing transmission power, by a femto base station, at its radio frequency (RF) transmitter, and cancelling a transmitted data signal of the RF transmitter at its network listen (NL) receiver. The reduction occurs in response to: occurrence of a network listen process; and/or a signal quality of the local macro coverage area exceeding a threshold quality. Additionally or alternatively, the femto base station may detect quality of its macro coverage area, and respond to the signal quality being below the threshold quality by: suspending reduction of transmission power and cancellation of the transmitted data signal; suspending the RF transmitter during transmission gaps assigned to user equipments (UEs); and triggering an NL operation in response to suspension of the RF transmitter, wherein the NL operation occurs within the duration of each of the transmission gaps.

Claims

1. A method for wireless communications, comprising:

reducing transmission power, by a femto base station, at a radio frequency (RF) transmitter of the femto base station; and

canceling a transmitted data signal, by the femto base station, at a network listen (NL) receiver of the femto base station during a network listen process of the femto base station, wherein the transmitted data signal was transmitted by the RF transmitter at the reduced transmission power,

wherein the reduction of transmission power occurs in response to at least one of;

occurrence of the network listen process;

or

a signal quality of a macro coverage area in which the femto base station is located exceeding a threshold quality.

2. The method of claim 1, wherein the canceling comprises at least one of:

canceling the transmitted data signal at an RF level;

canceling the transmitted data signal at a base band level;

or

canceling a portion of the transmitted data signal at the RF level and another portion of the transmitted data signal at the base band level.

3. The method of claim 1, further comprising:

detecting the signal quality of the macro coverage area in which the femto base station is located; and

in response to the signal quality being below the threshold quality;

suspending the reducing transmission power and the canceling the transmitted data signal;

suspending, by the femto base station, the RF transmitter of the femto base station during each of a plurality of transmission gaps assigned to one or more user equipments (UEs) in communication with the femto base station; and

triggering a network listen operation in response to the suspending the RF transmitter, wherein the network listen operation occurs within the duration of each of the plurality of transmission gaps.

4. The method of claim 3, further comprising:

detecting a gap of the plurality of transmission gaps;

in response to the detecting;

switching a transmission signal path away from the RF transmitter; and

switching the reception signal path to an NL module to perform the network listen operation.

5. The method of claim 3, further comprising:

assigning synchronous plurality of transmission gaps to each of the one or more UEs in communication with the femto base station.

6. The method of claim 3, further comprising:

identifying one or more voice users of the one or more UEs; and

assigning the plurality of transmission gaps to each of the identified one or more voice users.

7. An apparatus for wireless communications, said apparatus comprising:

means for reducing transmission power, by a femto base station, at a radio frequency (RF) transmitter of the femto base station; and

means for canceling a transmitted data signal during a network listen process of the femto base station, by the femto base station, at a network listen (NL) receiver of the femto base station, wherein the transmitted data signal was transmitted by the RF transmitter at the reduced transmission power,

wherein the means for reducing transmission power operatively reduces the transmission power in response to at least one of;

occurrence of the network listen process;

or

a signal quality of a macro coverage area in which the femto base station is located exceeding a threshold quality.

8. The apparatus of claim 7, wherein the means for canceling comprises at least one of:

means for canceling the transmitted data signal at an RF level;

means for canceling the transmitted data signal at a base band level;

or

means for canceling a portion of the transmitted data signal at the RF level and another portion of the transmitted data signal at the base band level.

9. The apparatus of claim 7, further comprising:

means for detecting the signal quality of the macro coverage area in which the femto base station is located; and

in response to the signal quality being below the threshold quality;

means for suspending the means for reducing transmission power and the means for canceling the transmitted data signal;

means for suspending, by the femto base station, the RF transmitter of the femto base station during each of a plurality of transmission gaps assigned to one or more user equipments (UEs) in communication with the femto base station; and

means for triggering a network listen operation in response to suspension of the RF transmitter, wherein the network listen operation occurs within the duration of each of the plurality of transmission gaps.

10. The apparatus of claim 9, further comprising:

means for detecting a gap of the plurality of transmission gaps;

in response to detection of the gap;

means for switching a transmission signal path away from the RF transmitter; and

means for switching the reception signal path to an NL module to perform the network listen operation.

11. The apparatus of claim 9, further comprising:

means for assigning synchronous plurality of transmission gaps to each of the one or more UEs in communication with the femto base station.

12. The apparatus of claim 9, further comprising:

means for identifying one or more voice users of the one or more UEs; and

means for assigning the plurality of transmission gaps to each of the identified one or more voice users.

13. A computer program product comprising:

a non-transitory computer-readable medium including;

code that, when enacted by one or more computer processors, causes the one or more computer processors to carry out one or more operations for reducing transmission power, by a femto base station, at a radio frequency (RF) transmitter of the femto base station; and

code that, when enacted by the one or more computer processors, causes the one or more computer processors to carry out one or more operations for canceling a transmitted data signal, by the femto base station, at a network listen (NL) receiver of the femto base station during a network listen process of the femto base station, wherein the transmitted data signal was transmitted by the RF transmitter at the reduced transmission power,

wherein the code that, when enacted by the one or more computer processors, causes the one or more computer processors to carry out one or more operations for reducing transmission power operatively reduces the transmission power in response to at least one of;

occurrence of the network listen process;

or

a signal quality of a macro coverage area in which the femto base station is located exceeding a threshold quality.

14. The computer program product of claim 13, wherein the non-transitory computer-readable medium includes at least one of:

code that, when enacted by the one or more computer processors, causes the one or more computer processors to carry out one or more operations for canceling the transmitted data signal at an RF level;

code that, when enacted by the one or more computer processors, causes the one or more computer processors to carry out one or more operations for canceling the transmitted data signal at a base band level;

or

code that, when enacted by the one or more computer processors, causes the one or more computer processors to carry out one or more operations for canceling a portion of the transmitted data signal at the RF level and another portion of the transmitted data signal at the base band level.

15. The computer program product of claim 13, wherein the non-transitory computer-readable medium further includes:

code that, when enacted by the one or more computer processors, causes the one or more computer processors to carry out one or more operations for detecting the signal quality of the macro coverage area in which the femto base station is located; and

in response to the signal quality being below the threshold quality;

code that, when enacted by the one or more computer processors, causes the one or more computer processors to carry out one or more operations for suspending the code that, when enacted by the one or more computer processors, causes the one or more computer processors to carry out one or more operations for reducing transmission power and the canceling the transmitted data signal;

code that, when enacted by the one or more computer processors, causes the one or more computer processors to carry out one or more operations for suspending, by the femto base station, the RF transmitter of the femto base station during each of a plurality of transmission gaps assigned to one or more user equipments (UEs) in communication with the femto base station; and

code that, when enacted by the one or more computer processors, causes the one or more computer processors to carry out one or more operations for triggering a network listen operation in response to suspension of the RF transmitter, wherein the network listen operation occurs within the duration of each of the plurality of transmission gaps.

16. The computer program product of claim 15, wherein the non-transitory computer-readable medium further includes:

code that, when enacted by the one or more computer processors, causes the one or more computer processors to carry out one or more operations for detecting a gap of the plurality of transmission gaps;

in response to detection of the gap;

code that, when enacted by the one or more computer processors, causes the one or more computer processors to carry out one or more operations for switching a transmission signal path away from the RF transmitter; and

code that, when enacted by the one or more computer processors, causes the one or more computer processors to carry out one or more operations for switching the reception signal path to an NL module to perform the network listen operation.

17. The computer program product of claim 15, wherein the non-transitory computer-readable medium further includes:

code that, when enacted by the one or more computer processors, causes the one or more computer processors to carry out one or more operations for assigning synchronous plurality of transmission gaps to each of the one or more UEs in communication with the femto base station.

18. The computer program product of claim 15, wherein the non-transitory computer-readable medium further includes:

code that, when enacted by the one or more computer processors, causes the one or more computer processors to carry out one or more operations for identifying one or more voice users of the one or more UEs; and

code that, when enacted by the one or more computer processors, causes the one or more computer processors to carry out one or more operations for assigning the plurality of transmission gaps to each of the identified one or more voice users.

19. A femto base station, the femto base station comprising:

at least one processor; and

a memory coupled to said at least one processor,

wherein said at least one processor is configured to;

reduce transmission power, by the femto base station, at a radio frequency (RF) transmitter of the femto base station; and

cancel a transmitted data signal, by the femto base station, at a network listen (NL) receiver of the femto base station during a network listen process of the femto base station, wherein the transmitted data signal was transmitted by the RF transmitter at the reduced transmission power, and

wherein said at least one processor operatively reduces transmission power in response to at least one of;

occurrence of the network listen process;

or

a signal quality of a macro coverage area in which the femto base station is located exceeding a threshold quality.

20. The femto base station of claim 19, wherein the at least one processor is further configured to at least one of:

cancel the transmitted data signal at an RF level;

cancel the transmitted data signal at a base band level;

or

cancel a portion of the transmitted data signal at the RF level and another portion of the transmitted data signal at the base band level.

21. The femto base station of claim 19, wherein the at least one processor is further configured to:

detect the signal quality of the macro coverage area in which the femto base station is located; and

in response to the signal quality being below the threshold quality;

suspend reduction of transmission power and cancelation of the transmitted data signal;

suspend, by the femto base station, the RF transmitter of the femto base station during each of a plurality of transmission gaps assigned to one or more user equipments (UEs) in communication with the femto base station; and

trigger a network listen operation in response to suspension of the RF transmitter, wherein the network listen operation occurs within the duration of each of the plurality of transmission gaps.

22. The femto base station of claim 21, wherein the at least one processor is further configured to:

detect a gap of the plurality of transmission gaps;

in response to detection of the gap;

switch a transmission signal path away from the RF transmitter; and

switch the reception signal path to an NL module to perform the network listen operation.

23. The femto base station of claim 21, wherein the at least one processor is further configured to:

assign synchronous plurality of transmission gaps to each of the one or more UEs in communication with the femto base station.

24. The femto base station of claim 21, wherein the at least one processor is further configured to:

identify one or more voice users of the one or more UEs; and

assign the plurality of transmission gaps to each of the identified one or more voice users.