Adaptive Equalization and Interference Cancellation with Time-Varying Noise and/or Interference

• US 20120201288A1
• Filed: 04/19/2012
• Published: 08/09/2012
• Est. Priority Date: 10/17/2007
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: CURRIVAN, Bruce J., KOLZE, Thomas Joseph
• Granted Patent: US 8,891,709 B2
• Time in Patent Office: Days
• US Class Current: 375/232
• CPC Class Codes: H04L 1/0056 Systems characterized by the type of code used H04L1/08 takes precedence
• CPC Class Codes: H04L 2025/03496 as a prediction filter
• CPC Class Codes: H04L 2025/03617 Time recursive algorithms H04L2025/03643 takes precedence
• CPC Class Codes: H04L 25/03019 adaptive, i.e. capable of adjustment during data reception
• CPC Class Codes: H04L 25/03038 with a non-recursive structure H04L25/03031 takes precedence
• CPC Class Codes: H04L 25/03057 with a recursive structure H04L25/03031 takes precedence
• CPC Class Codes: H04L 25/03286 with channel-decoding circuitry
• CPC Class Codes: H04L 25/067 providing soft decisions, i.e. decisions together with an estimate of reliability H04L25/068 and H04L25/069 take precedence; sequence estimation techniques H04L25/03178

Abstract

A method and apparatus is disclosed to compensate for interference and/or distortion impressed onto a transmitted communication signal in the presence of one or more time-varying noise and/or interference conditions. A communications receiver includes a noise analyzer to characterize the composition of the interference and/or the distortion and produce a selection signal indicating the composition of the interference and/or the distortion. The communications receiver selects at least one set of equalization coefficients and/or updates at least one parameter of a least-squares algorithm or the suitable equivalent algorithm to compensate for the interference and/or the distortion impressed onto a transmitted communication signal in the presence of a particular time-varying noise and/or interference condition.

Claims

1. A method for compensating the effects of a communication channel on a communication signal, comprising:

receiving analysis information related to the communication signal;

processing the analysis information to generate a metric of the communication signal;

comparing the generated metric to a plurality of stored metrics, each of the plurality of stored metrics corresponding to a respective condition of a plurality of conditions of the communication channel;

generating a hypothesis regarding a current condition of the communication channel based on the comparison of the generated metric to the plurality of stored metrics; and

configuring an equalizer based on the hypothesis; and

processing the communication signal using the equalizer to reduce the effects of the communication channel on the communication signal.

2. The method of claim 1, wherein the analysis information includes at least one of the communication signal, a slicer information signal generated from the communication signal, and a decoder information signal generated from the communication signal.

3. The method of claim 1, wherein the analysis information includes a frequency response of the communication signal.

4. The method of claim 1, wherein the processing of the analysis information is performed in non-real-time.

6. The method of claim 1, wherein the processing of the analysis information is performed in real-time.

7. The method of claim 1, wherein the hypothesis regarding the current condition of the communication channel includes one or more of presence/absence of a first condition and presence/absence of a second condition.

8. The method of claim 7, wherein at least one of the first condition and the second condition relates to noise and/or interference in the communication channel.

9. The method of claim 1, further comprising:

associating the generated metric with at least one condition of the plurality of conditions of the communication channel; and

storing the generated metric with the plurality of stored metrics.

10. The method of claim 1, further comprising:

updating at least one metric of the plurality of stored metrics using the generated metric, wherein the at least one metric is associated with the hypothesized current condition of the communication channel.

11. The method of claim 1, wherein configuring the equalizer comprises:

generating a coefficient selection signal based on the hypothesis;

producing equalization coefficients of the equalizer based on the coefficient selection signal; and

providing the equalization coefficients to the equalizer.

12. The method of claim 1, wherein configuring the equalizer comprises:

generating an equalizer selection signal based on the hypothesis, wherein the equalizer selection signal identifies the equalizer; and

updating equalization coefficients of the equalizer based on the equalizer selection signal.

5. The method of claim 5, further comprising:

analyzing a performance measure of the equalizer in processing the communication signal; and

updating the hypothesis based on the performance measure.

13. A communications receiver for compensating the effects of a communication channel on a communication signal, comprising:

a noise analyzer configured to process analysis information related to a communication signal and to generate a hypothesis regarding a current condition of the communication channel; and

an adaptive equalizer configured to process the communication signal based on the generated hypothesis.

14. The communications receiver of claim 13, wherein the noise analyzer is further configured to process the analysis information to generate a metric of the communication signal and to compare the generated metric to a plurality of stored metrics, each of the plurality of stored metrics corresponding to a respective condition of a plurality of conditions of the communication channel.

15. The communications receiver of claim 13, further comprising:

a slicer, coupled to the adaptive equalizer, configured to generate a slicer information signal; and

a decoder, coupled to the slicer, configured to generate a decoder information signal.

16. The communications receiver of claim 15, wherein the analysis information includes at least one of the communication signal, the slicer information signal, and the decoder information signal.

17. The communications receiver of claim 13, wherein the hypothesis regarding the current condition of the communication channel includes one or more of presence/absence of a first condition and presence/absence of a second condition.

18. The communications receiver of claim 17, wherein at least one of the first condition and the second condition relates to noise and/or interference in the communication channel.

19. The communications receiver of claim 13, wherein the noise analyzer is further configured to generate a coefficient selection signal based on the hypothesis, further comprising:

a coefficient generator configured to produce equalization coefficients of the adaptive equalizer based on the coefficient selection signal, and to provide the equalization coefficients to the adaptive equalizer.

20. A method for compensating the effects of a communication channel on a communication signal, comprising:

receiving analysis information related to the communication signal;

processing the analysis information to generate a metric of the communication signal;

comparing the generated metric to a plurality of stored metrics to generate a hypothesis regarding a presence of a first condition or a presence of a second condition of the communication channel;

configuring an equalizer based on the hypothesis; and

processing the communication signal using the equalizer to reduce the effects of the communication channel on the communication signal.