Method and system for I/Q mismatch calibration and compensation for wideband communication receivers
View Patent ↗Methods and systems for I/O mismatch calibration and compensation for wideband communication receivers may include receiving a radio frequency (RF) signal in a receiver of a communication device, down-sampling said received RF signal to generate a channel k and its image channel −k at baseband frequencies, determining average in-phase (I) and quadrature (Q) gain and phase mismatch of said channel k and said image channel −k, removing said average I and Q gain and phase mismatch of said channel k and said image channel −k, determining, after said removing said average I and Q gain and phase mismatch, a residual phase tilt of said channel k and said image channel −k, and compensating for said determined residual phase tilt of said channel k and said image channel −k utilizing a phase tilt correction filter.
1. A method for wireless communication, the method comprising:
in a communication device:
receiving a radio frequency (RF) signal in a receiver of said communication device;
down-sampling said received RF signal to generate a channel k and its image channel −k at baseband frequencies;
determining average in-phase (I) and quadrature (Q) gain and phase mismatch of said channel k and said image channel −k;
removing said average I and Q gain and phase mismatch of said channel k and said image channel −k;
determining, after said removing said average I and Q gain and phase mismatch, a residual phase tilt of said channel k and said image channel −k; and
compensating for said determined residual phase tilt of said channel k and said image channel −k utilizing a phase tilt correction filter by passing a signal through the phase tilt correction filter, wherein said signal comprises a sum of said channel k and said image channel −k shifted in frequency based on a determined curvature of said gain mismatch.
2. The method according to claim 1 , wherein said phase tilt correction filter comprises one or more all-pass filters.
3. The method according to claim 1 , wherein said receiver is a direct conversion receiver.
4. The method according to claim 1 , comprising determining said average I and Q gain and phase mismatch utilizing a blind source separation (BSS) estimation algorithm.
5. A system for wireless communication, the system comprising:
one or more circuits for use in a communication device, said one or more circuits being operable to:
receive a radio frequency (RF) signal in a receiver of said communication device;
down-sample said received RF signal to generate a channel k and its image channel −k at baseband frequencies;
determine average in-phase (I) and quadrature (Q) gain and phase mismatch of said channel k and said image channel −k;
remove said average I and Q gain and phase mismatch of said channel k and said image channel −k;
determine, after said removing said average I and Q gain and phase mismatch, a residual phase tilt of said channel k and said image channel −k; and
compensate for said determined residual phase tilt of said channel k and said image channel −k utilizing a phase tilt correction filter by passing a signal through the phase tilt correction filter, wherein said signal comprises a sum of said channel k and said image channel −k shifted in frequency based on a determined curvature of said gain mismatch.
6. The system according to claim 5 , wherein said phase tilt correction filter comprises one or more all-pass filters.
7. The system according to claim 5 , wherein said receiver is a direct conversion receiver.
8. The system according to claim 5 , wherein said one or more circuits are operable to determine said average I and Q gain and phase mismatch utilizing a blind source separation (BSS) estimation algorithm.
9. A system for wireless communication, the system comprising:
one or more circuits for use in a communication device, said one or more circuits being operable to:
receive a radio frequency (RF) signal in a receiver of said communication device;
down-sample said received RF signal to generate a channel k and its image channel −k at baseband frequencies;
determine average in-phase (I) and quadrature (Q) gain and phase mismatch of said channel k and said image channel −k utilizing an estimation algorithm;
average an estimating function of said estimation algorithm over a number of samples and update a separating matrix based on said averaging;
remove said average I and Q gain and phase mismatch of said channel k and said image channel −k;
determine, after said average I and Q gain and phase mismatch are removed, a residual phase tilt of said channel k and said image channel −k;
determine a curvature of gain mismatch for said channel k and said image channel −k; and
compensate for said determined residual phase tilt of said channel k and said image channel −k.
10. The system according to claim 9 , wherein said one or more circuits are operable to shift a frequency of said channel k and said image channel −k in a direction based on said determined curvature.
11. The system according to claim 9 , wherein said one or more circuits are operable to compensate for said determined residual phase tilt utilizing a phase tilt correction filter comprising one or more all-pass filters.
12. The system according to claim 9 , wherein said receiver is a direct conversion receiver.
13. A method for wireless communication, the method comprising:
in a communication device:
receiving a radio frequency (RF) signal in a receiver of said communication device;
down-sampling said received RF signal to generate a channel k and its image channel −k at baseband frequencies;
determining average in-phase (I) and quadrature (Q) gain and phase mismatch of said channel k and said image channel −k utilizing an estimation algorithm;
averaging an estimating function of said estimation algorithm over a number of samples and update a separating matrix based on said averaging;
removing said average I and Q gain and phase mismatch of said channel k and said image channel −k;
determining a curvature of gain mismatch for said channel k and said image channel −k;
determining, after said average I and Q gain and phase mismatch are removed, a residual phase tilt of said channel k and said image channel −k; and
compensating for said determined residual phase tilt of said channel k and said image channel −k.
14. The method according to claim 13 , comprising shifting a frequency of said channel k and said image channel −k in a direction based on said determined curvature.
15. The method according to claim 13 , comprising compensating for said determined residual phase tilt utilizing a phase tilt correction filter comprising one or more all-pass filters.
16. The method according to claim 13 , wherein said receiver is a direct conversion receiver.
17. A method for wireless communication, the method comprising:
in a communication device:
receiving a radio frequency (RF) signal in a receiver of said communication device;
down-sampling said received RF signal to generate a signal k and its image channel −k at baseband frequencies;
determining average in-phase (I) and quadrature (Q) gain and phase mismatch of said channel k and said image channel −k;
determining a curvature of gain mismatch for said channel k and said image channel −k;
removing said average I and Q gain and phase mismatch of said channel k and said image channel −k;
shifting a frequency of said channel k and said image channel −k in a direction based on said determined curvature;
determining, after said removing of said average I and Q gain and phase mismatch, a residual phase tilt of said channel k and said image channel −k; and
compensating for said determined residual phase tilt of said channel k and said image channel −k.
18. The method according to claim 17 , wherein a phase tilt correction filter is used for said compensating and comprises one or more all-pass filters.
19. The method according to claim 17 , wherein said receiver is a direct conversion receiver.
20. A system for wireless communication, the system comprising:
one or more circuits for use in a communication device, said one or more circuits being operable to:
receive a radio frequency (RF) signal in a receiver of said communication device;
down-sample said received RF signal to generate a signal k and its image channel −k at baseband frequencies;
determine average in-phase (I) and quadrature (Q) gain and phase mismatch of said channel k and said image channel −k;
determine a curvature of gain mismatch for said channel k and said image channel −k utilizing an estimation algorithm;
shift a frequency of said channel k and said image channel −k in a direction based on said determined curvature;
remove said average I and Q gain and phase mismatch of said channel k and said image channel −k;
determine, after said average I and Q gain and phase mismatch are removed, a residual phase tilt of said channel k and said image channel −k; and
compensate for said determined residual phase tilt of said channel k and said image channel −k.
21. The system according to claim 20 , wherein said one or more circuits are operable to compensate for said determined residual phase tilt utilizing a phase tilt correction filter comprising one or more all-pass filters.
22. The system according to claim 20 , wherein said one or more circuits are operable to average an estimating function of an estimation algorithm over a number of samples and update a separating matrix based on said averaging.
23. The system according to claim 20 , wherein said receiver is a direct conversion receiver.
24. A method for wireless communication, the method comprising:
in a communication device:
receiving a radio frequency (RF) signal in a receiver of said communication device;
down-sampling said received RF signal to generate a signal k and its image channel −k at baseband frequencies;
determining average in-phase (I) and quadrature (Q) gain and phase mismatch of said channel k and said image channel −k;
determining a curvature of gain mismatch for said channel k and said image channel −k;
removing said average I and Q gain and phase mismatch of said channel k and said image channel −k;
determining, after said removing of said average I and Q gain and phase mismatch, a residual phase tilt of said channel k and said image channel −k; and
compensating for said determined residual phase tilt of said channel k and said image channel −k, wherein a phase tilt correction filter is used for said compensating and comprises one or more all-pass filters.
25. The method according to claim 24 , wherein said receiver is a direct conversion receiver.
26. A system for wireless communication, the system comprising:
one or more circuits for use in a communication device, said one or more circuits being operable to:
receive a radio frequency (RF) signal in a receiver of said communication device;
down-sample said received RF signal to generate a signal k and its image channel −k at baseband frequencies;
determine average in-phase (I) and quadrature (Q) gain and phase mismatch of said channel k and said image channel −k;
determine a curvature of gain mismatch for said channel k and said image channel −k utilizing an estimation algorithm;
remove said average I and Q gain and phase mismatch of said channel k and said image channel −k;
determine, after said average I and Q gain and phase mismatch are removed, a residual phase tilt of said channel k and said image channel −k;
compensate for said determined residual phase tilt of said channel k and said image channel −k; and
average an estimating function of an estimation algorithm over a number of samples and update a separating matrix based on said averaging.
27. The system according to claim 26 , wherein said receiver is a direct conversion receiver.