Signal reception using non-linearity-compensated, partial response feedback
A receiver may receive a signal that was generated by passage of symbols through a non-linear circuit. An equalizer of the receiver may equalize the received signal based on a first non-linearity compensated, inter-symbol correlated (ISC) feedback signal to generate an equalized signal. The receiver may correct a phase error of the equalized signal to generate a phase-corrected equalized signal. The phase correction may be based on a second, non-linearity compensated, inter-symbol correlated (ISC) feedback signal.
1. A method comprising:
receiving, in a receiver, an inter-symbol correlated (ISC) signal;
equalizing, via an equalizer of said receiver, said received ISC signal to generate an equalized signal, wherein said equalizing is based on a first inter-symbol correlated (ISC) feedback signal; and
correcting, based on a second ISC feedback signal, a phase error of said equalized signal to generate a phase-corrected equalized signal,
wherein one or both of said first ISC feedback signal and said second ISC feedback signals are partial response signals.
2. A method comprising:
receiving, in a receiver, an inter-symbol correlated (ISC) signal;
equalizing, via an equalizer of said receiver, said received ISC signal to generate an equalized signal, wherein said equalizing is based on a first inter-symbol correlated (ISC) feedback signal;
correcting, based on a second ISC feedback signal, a phase error of said equalized signal to generate a phase-corrected equalized signal; and
generating said first ISC feedback signal,
wherein:
said received ISC signal passed through a non-linear circuit prior to said receiving; and
said generating said first ISC feedback signal comprises:
convolving an estimated symbol vector with a plurality of tap coefficients, said convolving resulting in a first estimated ISC signal;
phase adjusting said first estimated ISC signal to generate a second estimated ISC signal; and
applying a model of said non-linear circuit to said second estimated ISC signal.
3. The method of claim 2 , wherein said tap coefficients are based on tap coefficients of a partial response filter.
4. A method comprising:
receiving, in a receiver, an inter-symbol correlated (ISC) signal;
equalizing, via an equalizer of said receiver, said received ISC signal to generate an equalized signal, wherein said equalizing is based on a first inter-symbol correlated (ISC) feedback signal;
correcting, based on a second ISC feedback signal, a phase error of said equalized signal to generate a phase-corrected equalized signal; and
generating said second ISC feedback signal, wherein said generating said second ISC feedback signal comprises:
convolving an estimated symbol vector with a plurality of tap coefficients, said convolving resulting in a third estimated partial response signal; and
applying a model of a non-linear circuit to said third estimated partial response signal.
5. The method of claim 4 , wherein said tap coefficients are based on tap coefficients of a partial response filter.
6. A method comprising:
receiving, in a receiver, an inter-symbol correlated (ISC) signal;
equalizing, via an equalizer of said receiver, said received ISC signal to generate an equalized signal, wherein said equalizing is based on a first inter-symbol correlated (ISC) feedback signal;
correcting, based on a second ISC feedback signal, a phase error of said equalized signal to generate a phase-corrected equalized signal; and
controlling, during run-time of said receiver, a bandwidth of one or both of a first feedback loop comprising said first ISC feedback signal, and a second feedback loop comprising said second ISC feedback signal, said controlling being based on a measured performance indicator.
7. The method of claim 6 , wherein:
said controlling comprises adjusting one or more buffer index values;
a first one of said buffer index values corresponds to a buffer element that is read for generating said first ISC feedback signal; and
a second one of said buffer index values corresponds to a buffer element that is read for generating said second ISC feedback signal.
8. A system comprising: one or more circuits including an equalizer and a phase adjuster, said one or more circuits being operable to:
receive an inter-symbol correlated (ISC) signal;
equalize, via said equalizer, said received ISC signal to generate an equalized signal, wherein said equalizing is based on a first inter-symbol correlated (ISC) feedback signal; and
correct, via said phase adjuster based on a second ISC feedback signal, a phase error of said equalized signal to generate a phase-corrected equalized signal,
wherein one or both of said first ISC feedback signal and said second ISC feedback signals are partial response signals.
9. A system comprising: one or more circuits including an equalizer and a phase adjuster, said one or more circuits being operable to:
receive an inter-symbol correlated (ISC) signal;
equalize, via said equalizer, said received ISC signal to generate an equalized signal, wherein said equalizing is based on a first inter-symbol correlated (ISC) feedback signal; and
correct, via said phase adjuster based on a second ISC feedback signal, a phase error of said equalized signal to generate a phase-corrected equalized signal,
wherein:
said received ISC signal passed through a non-linear circuit en route to said equalizer;
said one or more circuits are operable to generate said first ISC feedback signal; and
said generation of said first ISC feedback signal comprises:
convolution of an estimated symbol vector with a plurality of tap coefficients, said convolution resulting in a first estimated partial response signal;
phase adjustment of said first estimated ISC signal to generate a second estimated ISC signal; and
application of a model of said non-linear circuit to said second estimated partial response signal.
10. The system of claim 9 , wherein said tap coefficients are based on tap coefficients of a partial response filter.
11. A system comprising:
one or more circuits including an equalizer and a phase adjuster, said one or more circuits being operable to:
receive an inter-symbol correlated (ISC) signal;
equalize, via said equalizer, said received ISC signal to generate an equalized signal, wherein said equalizing is based on a first inter-symbol correlated (ISC) feedback signal;
correct, via said phase adjuster based on a second ISC feedback signal, a phase error of said equalized signal to generate a phase-corrected equalized signal; and
generate said second ISC feedback signal, wherein said generation of said second ISC feedback signal comprises:
convolution of an estimated symbol vector with a plurality of tap coefficients, said convolution resulting in a third estimated partial response signal; and
application of a model of a non-linear circuit to said third estimated partial response signal.
12. The system of claim 11 , wherein said tap coefficients are based on tap coefficients of a partial response filter.
13. A system comprising: one or more circuits including an equalizer and a phase adjuster, said one or more circuits being operable to:
receive an inter-symbol correlated (ISC) signal;
equalize, via said equalizer, said received ISC signal to generate an equalized signal, wherein said equalizing is based on a first inter-symbol correlated (ISC) feedback signal; and
correct, via said phase adjuster based on a second ISC feedback signal, a phase error of said equalized signal to generate a phase-corrected equalized signal,
control, during run-time of said equalizer and/or said phase adjuster, a bandwidth of one or both of a first feedback loop comprising said first ISC feedback signal, and a second feedback loop comprising said second ISC feedback signal, said controlling being based on a measured performance indicator.
14. The method of claim 13 , wherein:
said controlling comprises adjusting one or more buffer index values;
a first one of said buffer index values corresponds to a buffer element that is read for generating said first ISC feedback signal; and
a second one of said buffer index values corresponds to a buffer element that is read for generating said second ISC feedback signal.
15. A receiver comprising:
an equalizer whose tap coefficients adapt based on a first inter-symbol correlated (ISC) feedback signal;
a carrier recovery circuit that attempts to correct phase error of a signal output by said equalizer based on a second ISC feedback signal;
a sequence estimation circuit that outputs one or more signals from which said first ISC feedback signal and said second ISC feedback signal are generated; and
a partial response filter, an output of which is input to said equalizer.
16. A receiver comprising:
an equalizer whose tap coefficients adapt based on a first inter-symbol correlated (ISC) feedback signal;
a carrier recovery circuit that attempts to correct phase error of a signal output by said equalizer based on a second ISC feedback signal;
a sequence estimation circuit that outputs one or more signals from which said first ISC feedback signal and said second ISC feedback signal are generated; and
circuitry operable to control, during run-time of said receiver, a bandwidth of one or both of a first feedback loop comprising said first ISC feedback signal, and a second feedback loop comprising said second ISC feedback signal, wherein said control is based on a measured performance indicator.
17. The receiver of claim 16 , wherein:
said control comprises adjustment of one or more buffer index values;
a first one of said buffer index values corresponds to a buffer element that is read for generating said first ISC feedback signal; and
a second one of said buffer index values corresponds to a buffer element that is read for generating said second ISC feedback signal.