Statistical channel analysis with correlated input patterns

1. A method comprising:

identifying, by a computing system, that a test input for a channel in an electronic device conforms to protocol having a correlated bit pattern;

determining, by the computing system, transition probabilities for bits in the test input based on the protocol having the correlated bit pattern;

measuring, by the computing system, a step response of the channel;

generating, by the computing system, an eye diagram by utilizing the transition probabilities to identify weightings for different bit transitions in the protocol having the correlated bit pattern and combining the portions of the step response of the channel based, at least in part, on the identified weightings for the different bit transitions, wherein the combined portions of the step response of the channel generate at least a portion of the eye diagram; and

predicting, by the computing system, a signal integrity of the channel from the eye diagram.

2. The method of claim 1 , wherein predicting the signal integrity of the channel further comprising generating a bit error rate for the channel from the eye diagram.

3. The method of claim 1 , further comprising identifying, by the computing system, correlation coefficients that describe the correlated bit pattern in the test input, wherein determining the transition probabilities for bits in the test input is performed based on the correlation coefficients.

4. The method of claim 1 , further comprising:

identifying, by the computing system, transmit jitter capable of being introduced by a transmitter of the test input onto the channel; and

determining, by the computing system, a vertical distribution of voltages in the step response of the channel based on the transmit jitter, wherein predicting the signal integrity of the channel is based on the vertical distribution of voltages in the step response of the channel and the transition probabilities for bits in the test input.

5. The method of claim 4 , wherein the transmit jitter includes at least one of random jitter or deterministic jitter.

6. The method of claim 4 , further comprising:

measuring, by the computing system, multiple step responses of the channel that differ based, at least in part, on values of one or more bits previously transmitted on the channel; and

determining, by the computing system, the vertical distributions of voltages in each of the multiple step responses of the channel based on the transmit jitter, wherein predicting the signal integrity of the channel is based on the vertical distribution of voltages in the step response of the channel and the transition probabilities for bits in the test input.

7. The method of claim 4 , further comprising setting, by the computing system, an offset for a bit interval on the channel, wherein predicting the signal integrity of the channel further comprising utilizing the transition probabilities and the vertical distributions to aggregate probability density functions for multiple points in the step response of the channel corresponding to the offset.

8. A system comprising:

a memory system configured to store computer-executable instructions; and

a computing system, in response to execution of the computer-executable instructions, is configured to:

identify that a test input for a channel in an electronic device conforms to protocol having a correlated bit pattern;

determine transition probabilities for bits in the test input based on the protocol having the correlated bit pattern;

measure a step response of the channel;

generate an eye diagram by utilizing the transition probabilities to identify weightings for different bit transitions in the protocol having the correlated bit pattern and combining the portions of the step response of the channel based, at least in part, on the identified weightings for the different bit transitions, wherein the combined portions of the step response of the channel generate at least a portion of the eye diagram; and

predict a signal integrity of the channel from the eye diagram.

9. The system of claim 8 , wherein the computing system, in response to execution of the computer-executable instructions, is further configured to predict the signal integrity of the channel by generating a bit error rate for the channel from the eye diagram.

10. The system of claim 8 , wherein the computing system, in response to execution of the computer-executable instructions, is further configured to:

identify correlation coefficients that describe the correlated bit pattern in the test input; and

determine the transition probabilities for bits in the test input based on the correlation coefficients.

11. The system of claim 8 , wherein the computing system, in response to execution of the computer-executable instructions, is further configured to:

identify transmit jitter capable of being introduced by a transmitter of the test input onto the channel;

determine a vertical distribution of voltages in the step response of the channel based on the transmit jitter; and

predict the signal integrity of the channel based on the vertical distribution of voltages in the step response of the channel and the transition probabilities for bits in the test input.

12. The system of claim 11 , wherein the computing system, in response to execution of the computer-executable instructions, is further configured to:

measure multiple step responses of the channel that differ based, at least in part, on values of one or more bits previously transmitted on the channel;

determine the vertical distributions of voltages in each of the multiple step responses of the channel based on the transmit jitter; and

predict the signal integrity of the channel based on the vertical distribution of voltages in the step response of the channel and the transition probabilities for bits in the test input.

13. The system of claim 11 , wherein the computing system, in response to execution of the computer-executable instructions, is further configured to:

set an offset for a bit interval on the channel; and

utilize the transition probabilities and the vertical distributions to aggregate probability density functions for multiple points in the step response of the channel corresponding to the offset.

14. An apparatus comprising at least one non-transitory computer-readable memory device storing instructions configured to cause one or more processing devices to perform operations comprising:

identifying that a test input for a channel in an electronic device conforms to protocol having a correlated bit pattern;

determining transition probabilities for bits in the test input based on the protocol having the correlated bit pattern;

measuring a step response of the channel;

generating an eye diagram by utilizing the transition probabilities to identify weightings for different bit transitions in the protocol having the correlated bit pattern and combining the portions of the step response of the channel based, at least in part, on the identified weightings for the different bit transitions, wherein the combined portions of the step response of the channel generate at least a portion of the eye diagram; and

predicting a signal integrity of the channel from the eye diagram.

15. The apparatus of claim 14 , wherein predicting the signal integrity of the channel further comprising generating a bit error rate for the channel from the eye diagram.

16. The apparatus of claim 14 , wherein the instructions are configured to cause the one or more processing devices to perform operations further comprising identifying correlation coefficients that describe the correlated bit pattern in the test input, wherein determining the transition probabilities for bits in the test input is performed based on the correlation coefficients.

17. The apparatus of claim 14 , wherein the instructions are configured to cause the one or more processing devices to perform operations further comprising:

identifying transmit jitter capable of being introduced by a transmitter of the test input onto the channel; and

determining a vertical distribution of voltages in the step response of the channel based on the transmit jitter, wherein predicting the signal integrity of the channel is based on the vertical distribution of voltages in the step response of the channel and the transition probabilities for bits in the test input.

18. The apparatus of claim 17 , wherein the transmit jitter includes at least one of random jitter or deterministic jitter.

19. The apparatus of claim 17 , wherein the instructions are configured to cause the one or more processing devices to perform operations further comprising:

measuring multiple step responses of the channel that differ based, at least in part, on values of one or more bits previously transmitted on the channel; and

determining the vertical distributions of voltages in each of the multiple step responses of the channel based on the transmit jitter, wherein predicting the signal integrity of the channel is based on the vertical distribution of voltages in the step response of the channel and the transition probabilities for bits in the test input.

20. The apparatus of claim 17 , wherein the instructions are configured to cause the one or more processing devices to perform operations further comprising:

setting an offset for a bit interval on the channel; and

utilizing the transition probabilities and the vertical distributions to aggregate probability density functions for multiple points in the step response of the channel corresponding to the offset.