Adjusting a continuous time linear equalization-based receiver
View Patent ↗Devices and methods for adjusting operation of a receiver that includes a continuous time linear equalizer, a decision feedback equalizer, and a feed forward equalizer. Operation of the receiver may be controlled by determining whether the receiver is operating in operation region using frequency responses of the feed forward equalizer at a first frequency and a second frequency and using the frequency responses of the decision feedback equalizer at the first frequency and the second frequency. If the operation is outside the frequency, a parameter of the continuous time linear equalizer is adjusted based on the frequency responses of the feed forward equalizer and the decision feedback equalizer.
1. A method for adapting operation of a continuous time linear equalizer system comprising:
determining a frequency response of a feed forward equalizer;
determining a frequency response of a decision feedback equalizer; and
adjusting a parameter of a continuous time linear equalizer based at least in part on a Nyquist response of the decision feedback equalizer, a direct current response of the decision feedback equalizer, a Nyquist response of the feed forward equalizer, a direct current response of the feed forward equalizer, and a threshold of a region of operation of the continuous time linear equalizer.
2. The method of claim 1 , wherein the Nyquist response of the feed forward equalizer is at a Nyquist frequency of an analog-to-digital convertor.
3. The method of claim 1 , wherein the Nyquist response of the decision feedback equalizer is at a Nyquist frequency of an analog-to-digital convertor.
4. The method of claim 1 , wherein adjusting a parameter of the continuous time linear equalizer comprises adjusting a peaking of the continuous time linear equalizer.
5. The method of claim 4 , wherein adjusting the peaking of the continuous time linear equalizer comprises increasing or decreasing a resistance of the continuous time linear equalizer.
6. The method of claim 1 , wherein adjusting the parameter of a continuous time linear equalizer comprises increasing the parameter when the following is true:
H nyq *F dc <F nyq *H dc *th _low
where H nyq is the Nyquist response of the decision feedback equalizer, H dc is the direct current response of the decision feedback equalizer, F nyq is the Nyquist response of the feed forward equalizer, F dc is the direct current response of the feed forward equalizer, and th_low is a lower end threshold of a region of operation of the continuous time linear equalizer.
7. The method of claim 1 , wherein adjusting the parameter of a continuous time linear equalizer comprises increasing the parameter when the following is true:
H nyq *F dc >F nyq *H dc *th _high
where H nyq is the Nyquist response of the decision feedback equalizer, H dc is the direct current response of the decision feedback equalizer, F nyq is the Nyquist response of the feed forward equalizer, F dc is the direct current response of the feed forward equalizer, and th_high is a higher end threshold of a region of operation of the continuous time linear equalizer.
8. The method of claim 7 , wherein the parameter comprises peaking of the continuous time linear equalizer.
9. A receiver comprising:
a continuous time linear equalizer that receives a signal via a channel;
a feed forward equalizer that receives the signal from the continuous time linear equalizer and filters out some interference from the signal;
a decision feedback equalizer that:
receives the signal from the feed forward equalizer;
filters the signal; and
outputs an output signal; and
a processor that adjusts a parameter of the continuous time linear equalizer based at least in part on a Nyquist response of the decision feedback equalizer, a direct current response of the decision feedback equalizer, a Nyquist response of the feed forward equalizer, a direct current response of the feed forward equalizer, and a threshold of a region of operation of the continuous time linear equalizer.
10. The receiver of claim 9 , wherein the Nyquist response of the decision feedback equalizer comprises a response of the decision feedback equalizer at a Nyquist frequency for the receiver.
11. The receiver of claim 10 , wherein the Nyquist response of the feed forward equalizer occurs at a Nyquist frequency of the receiver.
12. The receiver of claim 11 comprising an analog-to-digital converter, wherein the Nyquist frequency of the receiver comprises a Nyquist frequency of the analog-to-digital converter.
13. A method for adapting operation of a continuous time linear equalizer system comprising:
determining whether a continuous time linear equalizer-based receiver is operating in operation region using frequency responses of a feed forward equalizer of the receiver at a first frequency and a second frequency and using frequency responses of a decision feedback equalizer of the receiver at the first frequency and the second frequency; and
adjusting a parameter of a continuous time linear equalizer of the receiver based at least in part on a Nyquist response of the decision feedback equalizer, a direct current response of the decision feedback equalizer, a Nyquist response of the feed forward equalizer, a direct current response of the feed forward equalizer, and a threshold of a region of operation of the continuous time linear equalizer.
14. The method of claim 13 , wherein the parameter comprises peaking of the continuous time linear equalizer.
15. The method of claim 13 , wherein adjusting the parameter comprises adjusting a resistance of the continuous time linear equalizer.
16. The method of claim 13 , wherein the first frequency comprises a Nyquist frequency of the receiver, and the second frequency comprises 0 Hz.