System and method for adjusting phase

• US 7,068,706 B2
• Filed: 10/15/2003
• Issued: 06/27/2006
• Est. Priority Date: 10/15/2002
• Status: Expired due to Term

• Current Assignee: III Holdings 1, LLC (Intellectual Ventures LLC)
• Original Assignee: TensorComm, Inc. (Rambus Inc.)
• Inventors: Narayan, Anand P., Jain, Prashant, Olson, Eric S.
• Primary Examiner(s): Kumar, Pankaj
• Application Number:
  US10/686,359
• Publication Number:
  US 20040081229A1
• Time in Patent Office: 986 Days
• Field of Search: 375/371, 375373-376, 375/327, 375/147, 375/140, 375/130, 375/323, 375/322, 375/316, 375/354, 375/324, 375/346, 375/350, 327/329, 327/309, 327/306, 327/100, 370/209, 370/208, 370/203
• US Class Current: 375/147
• CPC Class Codes: H04J 13/0048 Walsh
• CPC Class Codes: H04L 2027/0046 Open loops

Abstract

Systems and methods for adjusting phase of a signal are provided. In one embodiment, the system includes a phase compensator configured for adjusting phase of the signal based on filtered and unfiltered representations of a first component of the signal and based on filtered and unfiltered representations of a second component of the signal. For example, the phase compensator may provide phase adjusted I and Q components of a complex signal through a plurality of multiplications of filtered and unfiltered I and Q components. The system also includes a detector that is communicatively coupled to the phase compensator. The detector is configured for combining the first and the second components with a code sequence to determine a complex amplitude of a channel.

Claims

1. A system, comprising:

a phase compensator configured for adjusting phase of a signal based on filtered and unfiltered representations of a first component of the signal and based on filtered and unfiltered representations of a second component of the signal; and

a detector communicatively coupled to one or more outputs of the phase compensator and configured for combining the first and the second components with at least one code sequence to determine a complex amplitude of a channel, wherein the detector further comprises;

at least one code sequence generator configured for generating the at least one code sequence that is unique

a first multiplier communicatively coupled to the code sequence generators and configured for combining the first component with one or more of the code sequences to generate a combined first component; and

a second multiplier communicatively coupled to the code sequence generators and configured for combining the second component with one or more of the code sequences to generate a combined second component.

2. The system of claim 1, wherein the detector further comprises an accumulator communicatively coupled to the first and the second multipliers for summing the combined first component over a symbol duration to generate a first symbol level data and for summing the combined second component over a symbol duration to generate a second symbol level data.

3. The system of claim 1, wherein the first component is an in-phase component substantially conforming to the following:

Y_I=|G|X_I cos φ

+|G|X_Q sin φ

, where

X_I is an unfiltered representation of the in-phase component, |G| cost is a filtered representation of the in-phase component, X_Q is an unfiltered representation of a quadrature component, and |G| sin φ

is a filtered representation of the quadrature component.

4. The system of claim 1, wherein the second component is a quadrature component substantially conforming to the following:

Y_Q=|G|X_Q cos φ

−

|G|X_I sin φ

, where

X_I is an unfiltered representation of an in-phase component, |G| cos φ

is the filtered representation of the in-phase component, X_Q is an unfiltered representation of the quadrature component, and |G| sin φ

is a filtered representation of the quadrature component.

5. The system of claim 1, wherein the code sequence is a Walsh code sequence.

6. The system of claim 1, wherein the detector comprises a fast Walsh transform element configured for combining the first and the second components with a plurality of Walsh code sequences to determine complex amplitudes of one or more unique channels.

7. A method of adjusting phase of a signal, comprising:

generating a phase adjusted first component of the signal by

a first multiplying step an unfiltered first component of the signal with a filtered first component of the signal to provide a first product,

a second multiplying step an unfiltered second component of the signal with a filtered second component of the signal to provide a second product, and

combining the first and the second products in response to the second multiplying step to generate the phase adjusted first component; and

generating a phase adjusted second component of the signal by

a third multiplying step the unfiltered second component with the filtered first component to provide a third product,

a fourth multiplying step the unfiltered first component with the filtered second component to provide a fourth product, and

combining the third and the fourth products in response to the fourth multiplying step to generate the phase adjusted second component, wherein generating the phase adjusted first component and generating the phase adjusted second component adjusts the phase of the signal.

8. The method of claim 7, wherein combining the first and the second products comprises adding the first product to the second product.

9. The method of claim 8, wherein adding comprises providing the phase adjusted second component having substantially the following form:

Y_I=|G|X_I cos φ

+|G|X_Q sin φ

, where

X_I is an unfiltered representation of an in-phase component, |G| cos φ

is a filtered representation of the in-phase component, X_Q is an unfiltered representation of a quadrature component, and |G| sin φ

is a filtered representation of the quadrature component.

10. The method of claim 7, wherein combining the third and the fourth products comprises subtracting the fourth product from the third product.

11. The method of claim 10, wherein the subtracting comprises providing the phase adjusted second component having substantially the following form:

Y_Q=|G|X_Q cost φ

|G|X_I sin φ

, where

X_I is a unfiltered representation of an in-phase component, |G| cos φ

is a filtered representation of the in-phase component, X_Q is an unfiltered representation of a quadrature component and |G| sin φ

is a filtered representation of the quadrature component.

12. The method of claim 7, wherein generating the phase adjusted first component, comprises:

latching the first product and the second product to a summation element at substantially the same time.

13. The method of claim 7, wherein generating the phase adjusted second component, comprises:

latching the third product and the fourth product to a subtractive element at substantially the same time.

14. A system for adjusting phase of a signal, comprising:

means for generating a phase adjusted first component of the signal comprising

first means for multiplying an unfiltered first component of the signal with a filtered first component of the signal to provide a first product,

second means for multiplying an unfiltered second component of the signal with a filtered second component of the signal to provide a second product, and

means for combining the first and the second products in response to the second multiplying means to generate the phase adjusted first component; and

means for generating a phase adjusted second component of the signal comprising

third means for multiplying the unfiltered second component with the filtered first component to provide a third product,

fourth means for multiplying the unfiltered first component with the filtered second component to provide a fourth product, and

means for combining the third and the fourth products in response to the fourth multiplying means to generate the phase adjusted second component, wherein the means for generating the phase adjusted first component and the means for generating the phase adjusted second component are configured to adjust the phase of the signal.

15. The system of claim 14, wherein the means for combining the first and the second products comprises means for adding the first product to the second product.

16. The system of claim 15, wherein the means for adding comprises means for providing the phase adjusted second component having substantially the following form:

Y_I=|G|X_I cos φ

+|G|X_Q sin φ

, where

X_I is an unfiltered representation of an in-phase component, |G| cos φ

is a filtered representation of the in-phase component, X_Q is an unfiltered representation of a quadrature components and |G| sin φ

is a filtered representation of the quadrature component.

17. The system of claim 14, wherein the means for combining the third and the fourth products comprises means for subtracting the fourth product from the third product.

18. The system of claim 17, wherein the means for subtracting comprises means for providing the phase adjusted second component having substantially the following form:

Y_Q=|G|X_Q cos φ

−

|G|X_I sin φ

, where

X_I is an unfiltered representation of an in-phase component, |G| cos φ

is a filtered representation of the in-phase component, X_Q is an unfiltered representation of Ha quadrature component and |G| sin φ

is a filtered representation of the quadrature component.

19. The system of claim 14, wherein the means for generating the phase adjusted first component, comprises:

means for latching the first product and the second product to a summation element at substantially the same time.

20. The system of claim 14, wherein the means for generating the phase adjusted first component, comprises:

means for latching the third product and the fourth product to a subtractive element at substantially the same time.

21. A method for processing a signal, comprising:

adjusting phase of a first component of the signal through a plurality multiplications, operands of which include filtered and unfiltered representations of the first component and which include filtered and unfiltered representations of a second component of the signal, to generate a phase adjusted first component;

adjusting phase of the second component through a plurality multiplications, operands of which include the filtered and the unfiltered representations of the first component and which include the filtered and the unfiltered representations of the second component, to generate a phase adjusted second component;

combining the phase adjusted first component and the phase adjusted second component with a code sequence to determine a complex amplitude of a channel.

22. The method of claim 21, wherein adjusting the phase of the first component comprises adding products generated from the multiplications to generate the phase adjusted first component having substantially the following form:

Y_I=|G|X_I cos φ

+|G|X_Q sin φ

, where

X_I is an unfiltered representation of an in-phase component, |G| cos φ

is a filtered representation of the in-phase component, X_Q is an unfiltered representation of a quadrature components and |G| sin φ

is a filtered representation of the quadrature component.

23. The method of claim 21, wherein adjusting the phase of the second component comprises adding products generated from the multiplications to generate the phase adjusted second component having substantially the following form:

Y_Q=|G|X_Q cost φ

−

|G|X_I sin φ

, where

X_I is an unfiltered representation of an in-phase component, |G| cos φ

is a filtered representation of the in-phase component, X_Q is an unfiltered representation of a quadrature component, and |G| sin φ

is a filtered representation of the quadrature component.