Fast stressed-eye calibration for receiving testing

Patent metadata

Field	Value
Publication number	US-12436189-B2
Application number	US-202117549559-A
Country	US
Kind code	B2
Filing date	Dec 13, 2021
Priority date	Dec 18, 2020
Publication date	Oct 7, 2025
Grant date	Oct 7, 2025

Abstract

A method of generating a calibration signal includes setting a first parameter to an initial first value and a second parameter to an initial second value, generating an initial eye diagram using the initial first value and the initial second value, determining a first difference between a first dimension of the initial eye diagram and a target first dimension, and a second difference between a second dimension of the initial eye diagram and a second target dimension, estimating a next first value to cause the first difference to be zero, setting the first parameter to the next first value, generating a next eye diagram, repeating the estimating, setting, and generating until the first dimension of a most recent next eye diagram is within the first target dimension, setting a final first parameter value to a most recent next first value, setting a final second parameter value to the initial second value when the second dimension of the most recent next eye diagram is within the second target dimension, generating a calibration signal in accordance with the final first parameter value and the final second parameter value. A test and measurement device includes a user interface, at least one channel configured to connect to a device under test, a memory, and one or more processors configured to execute code to make the processors able to implement a process such as above.

First claim

The invention claimed is:

1. A test and measurement device, comprising:
a user interface;
at least one channel configured to connect to a device under test;
a memory; and
one or more processors configured to execute code that cause the one or more processors to:
set a first parameter to an initial first value and a second parameter to an initial second value;
generate an initial eye diagram using the initial first value and the initial second value, where generating an eye diagram comprises:
receiving a signal;
repetitively sampling the signal;
applying the sample to a vertical input while triggering a horizontal sweep to generate the initial eye diagram; and

determine a first difference between a first dimension of the initial eye diagram and a target first dimension, and a second difference between a second dimension of the initial eye diagram and a second target dimension;
estimate a next first value to cause the first difference to be zero;
set the first parameter to the next first value;
generate a next eye diagram;
repeat the estimating, setting, and generating until the first dimension of a most recent next eye diagram is within the first target dimension;
set a final first parameter value to a most recent next first value;
set a final second parameter value to the initial second value when the second dimension of the most recent next eye diagram is within the second target dimension;
generate a calibration signal in accordance with the final first parameter value and the final second parameter value;
provide the calibration signal to a user through the user interface with a least number of repetitions and less time than previously approaches;
use the calibration signal to calibrate the device under test for testing.

2. The device as claimed in claim 1 , wherein, when the second dimension of the most recent next eye diagram is not within the second target dimension, the code further causes the one or more processors to:
estimate a next second value to cause the second difference to be zero;
set the second parameter to the next second value;
generate a next eye diagram;
repeat the estimating, setting, and generating until the second dimension of the most recent next eye diagram is within the second target dimension; and
set the final second parameter value to a most recent next second value.

3. The device as claimed in claim 2 , wherein the code further causes the one or more processors to set a difference between the first dimension and the target first dimension to a constant value.

4. The device as claimed in claim 1 , wherein the code to cause the one or more processors to estimate the next first value for the first parameter to cause the first difference to be zero comprises code to cause the one or more processors to:
determine a change in the first parameter and the second parameter correlating to the first difference and the second difference; and
estimate the first parameter based upon the change in the first parameter.

5. The device as claimed in claim 4 , wherein the code that causes the one or more processors to estimate the first parameter comprises code to cause the one or more processors to estimate the first parameter based upon the change in the first parameter and a mapping of a change in the second parameter to the first parameter.

6. The device as claimed in claim 1 , wherein the repeating only occurs once and the final second parameter value is set to the initial second value.

7. The device as claimed in claim 1 , wherein the first parameter is differential mode interference and the second parameter is sinusoidal jitter.

8. The device as claimed in claim 1 , wherein the first parameter is sinusoidal jitter and the second parameter is amplitude.

9. The device as claimed in claim 1 , wherein the first parameter is random jitter and the second parameter is differential mode interference.

10. The test and measurement device as claimed in claim 1 , wherein the test and measurement device further comprises a waveform generator.

11. A method of generating a calibration signal, comprising:
setting a first parameter to an initial first value and a second parameter to an initial second value;
generating an initial eye diagram using the initial first value and the initial second value, wherein generating an eye diagram comprises:
receiving a signal;
repetitively sampling the signal; and
applying the sample to a vertical input while triggering a horizontal sweep to generate the initial eye diagram;

determining a first difference between a first dimension of the initial eye diagram and a target first dimension, and a second difference between a second dimension of the initial eye diagram and a second target dimension;
estimating a next first value to cause the first difference to be zero;
setting the first parameter to the next first value;
generating a next eye diagram;
repeating the estimating, setting, and generating until the first dimension of a most recent next eye diagram is within the first target dimension;
setting a final first parameter value to a most recent next first value;
setting a final second parameter value to the initial second value when the second dimension of the most recent next eye diagram is within the second target dimension;
generating a calibration signal in accordance with the final first parameter value and the final second parameter value;
providing the calibration signal to a user through a user interface with a least number of repetitions and far less time than previously possible; and
using the calibration signal to calibrate the device under test for testing.

12. The method as claimed in claim 11 , further comprising, when the second dimension of the most recent next eye diagram is not within the second target dimension:
estimating a next second value to cause the second difference to be zero;
setting the second parameter to the next second value;
generating a next eye diagram;
repeating the estimating, setting, and generating until the second dimension of the most recent next eye diagram is within the second target dimension; and
setting the final second parameter value to a most recent next second value.

13. The method as claimed in claim 12 , further comprising setting a difference between the first dimension and the target first dimension to a constant value.

14. The method as claimed in claim 11 , wherein estimating the next first value for first parameter causes the first difference to be zero comprises:
determining a change in the first parameter and the second parameter correlating to the first difference and the second difference; and
estimating the first parameter based upon the change in the first parameter.

15. The method as claimed in claim 14 , wherein estimating the first parameter comprises estimating the first parameter based upon the change in the first parameter and a mapping of a change in the second parameter to the first parameter.

16. The method as claimed in claim 11 , wherein the repeating only occurs once and the final second parameter value is set to the initial second value.

17. The method as claimed in claim 11 , wherein the first parameter is differential mode interference and the second parameter is sinusoidal jitter.

18. The method as claimed in claim 11 , wherein the first parameter is sinusoidal jitter and the second parameter is amplitude.

19. The method as claimed in claim 11 , wherein the first parameter is random jitter and the second parameter is differential mode interferen

Assignees

• Tektronix Inc

Inventors

• Ghose Subhankar
• Dash Ankit
• Bouse David M

Classifications

• G01R31/3171 Primary

  BER [Bit Error Rate] test · CPC title

• G06F11/22 Primary

  Detection or location of defective computer hardware by testing during standby operation or during idle time, e.g. start-up testing · CPC title