Correlation-based self-interference suppression

• US 9,781,612 B2
• Filed: 03/31/2014
• Issued: 10/03/2017
• Est. Priority Date: 03/31/2014
• Status: Expired due to Fees

• Current Assignee: Intel Corporation
• Original Assignee: Intel IP Corporation (Intel Corporation)
• Inventors: Buskgaard, Emil, Tsakalaki, Elpiniki, Alrabadi, Osama Nafeth, Knudsen, Mikael Bergholz, Pedersen, Gert, Tatomirescu, Alexandru Daniel, Olesen, Poul, Bundgaard, Peter, Bahramzy, Pevand
• Primary Examiner(s): CATTUNGAL, AJAY P
• Application Number:
  US14/231,679
• Publication Number:
  US 20160373939A1
• Time in Patent Office: 1,282 Days
• CPC Class Codes: H04B 1/525 with means for reducing leakage of transmitter signal into the receiver
• CPC Class Codes: H04B 17/12 of transmit antennas, e.g. of the amplitude or phase
• CPC Class Codes: H04B 7/0617 for beam forming
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition
• CPC Class Codes: H04W 72/20 Control channels or signalling for resource management
• CPC Class Codes: H04W 72/541 using the level of interference
• CPC Class Codes: H04W 88/02 Terminal devices
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

Representative implementations of devices and techniques provide self-interference suppression for a transceiver of a wireless communication system. To minimize interference from a transmit signal appearing on a receive path of the system, a cross-correlation is minimized between the transmit signal and a desired receive signal.

Claims

1. An apparatus, comprising:

a filter component arranged to generate a complex antenna weight based on a cross-correlation value, the cross-correlation value based on a cross-correlation between one or more transmit signals of a transmit path of a transceiver and at least one receive signal of a receive path of the transceiver, the at least one receive signal comprising either a desired receive signal for the receive path or a received signal at the receive path, to modify a magnitude or a phase of the one or more transmit signals of the transceiver based on the complex antenna weight, and to suppress leakage of at least one of the one or more transmit signals to the receive path of the transceiver based on the modification.

2. The apparatus of claim 1, wherein the cross-correlation value is based on a temporal cross-correlation between the one or more transmit signals and the received signal at the receive path.

3. The apparatus of claim 2, further comprising a controller arranged to control a generation or an adjustment of the complex antenna weight by the filter component, the temporal cross-correlation comprising an objective function to be minimized by the controller.

4. The apparatus of claim 3, wherein the filter component is arranged to calibrate the controller by taking one or more error measurements based on an estimated complex antenna weight and to determine the cross-correlation value based on the error measurements, and to optimize the temporal cross-correlation by an iterative process using the cross-correlation value to determine an optimal complex antenna weight.

5. The apparatus of claim 1, wherein the filter component is arranged to dynamically and continuously adjust the complex antenna weight based on a value of the cross-correlation between the one or more transmit signals and the received signal at the receive path exceeding a previous cross-correlation value and the cross-correlation value exceeding a preset threshold.

6. A communication system, comprising:

a transmit path of a transceiver, the transmit path including one or more transmit antennas;

a receive path of the transceiver, the receive path including a receive antenna susceptible to leakage from the transmit path;

a computational component arranged to determine a cross-correlation value based on a cross-correlation between one or more transmit signals of the transmit path and a desired receive signal for the receive path; and

a filter component arranged to generate a complex weight value based on the cross-correlation value, to modify a magnitude ora phase of one or more of the transmit signals based on the complex weight value, and to suppress leakage of at least one of the one or more transmit signals to the receive path based on the modification.

7. The system of claim 6, further comprising a balun component arranged to balance gains and phases of the one or more transmit antennas to generate or steer a null in a direction of the receive antenna.

8. The system of claim 6, wherein the filter component is further arranged to generate a cancellation signal via the complex weight value, the cancellation signal arranged to cancel the leakage from the transmit path.

9. The system of claim 8, wherein the cancellation signal comprises a signal having an equal magnitude and an opposite phase as the leakage from the transmit path.

10. The system of claim 8, wherein the filter component is further arranged to generate the cancellation signal by modifying a phase or a magnitude of one or more of the transmit signals.

11. The system of claim 8, wherein the filter component is further arranged to dynamically and continuously maintain the cancellation signal equal in magnitude and opposite in phase to the leakage from the transmit path.

12. The system of claim 11, wherein the filter component is further arranged to track the leakage from the transmit path and to dynamically and continuously adjust the complex weight value for maximum isolation between the transmit path and the receive path.

13. The system of claim 8, wherein the filter component is arranged to generate the cancellation signal via iterative steps proportional to a negative of an approximate gradient of a cross-correlation function at a current point.

14. The system of claim 13, wherein the filter component is arranged to approximate the gradient of the cross-correlation function with respect to the complex weight value via a finite difference quotient estimate.

15. A method, comprising:

determining a cross-correlation value based on a cross-correlation between one or more transmit signals of a transceiver and a desired receive signal for the transceiver;

generating a complex weight value based on the cross-correlation value;

modifying a magnitude or a phase of one or more of the transmit signals based on the complex weight value; and

suppressing leakage of at least one of the one or more transmit signals to a receive path of the transceiver based on the modifying.

16. The method of claim 15, further comprising minimizing the cross-correlation between the one or more transmit signals and the desired receive signal via adjusting the complex weight value.

17. The method of claim 15, further comprising generating the complex weight value via an iterative, gradient-based optimization process arranged to converge to a minimum cross-correlation value within a threshold quantity of iterations.

18. The method of claim 17, further comprising tuning a spatial filter or an active filter of the transceiver using the optimization process.

19. The method of claim 17, further comprising converging to the complex weight value using an objective function comprising the cross-correlation between the one or more transmit signals and the desired receive signal.

20. The method of claim 15, further comprising dynamically tuning the complex weight value for maximum isolation between transmit antennas of the transceiver and a receive antenna of the receiver.

21. The method of claim 20, further comprising monitoring the isolation between the transmit antennas and the receive antenna via monitoring the cross-correlation between the one or more transmit signals and the desired receive signal.

22. The method of claim 21, further comprising comparing the cross-correlation to a past cross-correlation and to a threshold cross-correlation to determine whether to update the cross-correlation value.

23. The method of claim 22, further comprising updating the cross-correlation value when the cross-correlation is greater than the past cross-correlation and the cross-correlation is greater than the threshold cross-correlation.

24. The method of claim 15, further comprising suppressing leakage of a transmit signal of the transceiver based on a first radio standard to a receive path of the transceiver based on a second, different radio standard via generating a cancellation signal based on a minimum cross-correlation between the transmit signal of the first radio standard and a desired receive signal of the second radio standard.

25. The method of claim 15, further comprising providing noise cancellation of a high frequency noise from an on-board source of the transceiver to a receive path of the transceiver via minimizing a cross-correlation between the high frequency noise and the receive path using an optimization process based on an objective function comprising the cross-correlation between the high frequency noise and a desired receive signal of the receive path.