Eye Closure Penalty Calculator
Audit actual eye-opening loss versus measured reference in voltage/UI and amplitude-equivalent dB; negative closure/improvement retained, not optical power penalty, calibrated BER or receiver margin.
Description
Eye closure compares measured openings with reference openings.
Eye closure compares measured openings with reference openings. Improved openings yield negative closure and penalty.1
Enter four positive reference/observed vertical volts and horizontal UI values. Return signed closure fractions and amplitude-equivalent dB penalty.
When to use Eye Closure Penalty Calculator
Use Eye Closure Penalty Calculator when you need to evaluate the supplied records under the calculation and evidence rules below. No optical power penalty, calibrated BER or receiver-margin inference is supplied.
Prepare measured device or circuit evidence with matched frequency, temperature, waveform and calibration conditions. Supply explicit caller ratings and limits.
How to use Eye Closure Penalty Calculator and understand its results
- Prepare measured device or circuit evidence with matched frequency, temperature, waveform and calibration conditions. Supply explicit caller ratings and limits.
- Enter referenceVerticalEyeOpeningV, observedVerticalEyeOpeningV, referenceHorizontalEyeOpeningUi, observedHorizontalEyeOpeningUi using the field table and calculation rules, then run the tool.
- Read verticalEyeClosureFraction, horizontalEyeClosureFraction, amplitudeEquivalentEyePenaltyDb. The explanation below defines the units, signs, ordering and any flags or placeholder values.
- If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.
| Input field | Meaning | Value type; see rules below | Requirement |
|---|---|---|---|
| referenceVerticalEyeOpeningV | Reference vertical eye opening v | number | Required |
| observedVerticalEyeOpeningV | Observed vertical eye opening v | number | Required |
| referenceHorizontalEyeOpeningUi | Reference horizontal eye opening ui | number | Required |
| observedHorizontalEyeOpeningUi | Observed horizontal eye opening ui | number | Required |
Enter four positive reference/observed vertical volts and horizontal UI values. Return signed closure fractions and amplitude-equivalent dB penalty.
closure=1−observed/reference; amplitudePenalty=20log10(referenceVertical/observedVertical) Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.
| Output field | Meaning | Value type |
|---|---|---|
| verticalEyeClosureFraction | Vertical eye closure fraction | number |
| horizontalEyeClosureFraction | Horizontal eye closure fraction | number |
| amplitudeEquivalentEyePenaltyDb | Amplitude equivalent eye penalty db | number |
{
"input": {
"referenceVerticalEyeOpeningV": 1,
"observedVerticalEyeOpeningV": 0.5,
"referenceHorizontalEyeOpeningUi": 1,
"observedHorizontalEyeOpeningUi": 0.75
},
"output": {
"verticalEyeClosureFraction": 0.5,
"horizontalEyeClosureFraction": 0.25,
"amplitudeEquivalentEyePenaltyDb": 6.020599913279624
}
}Limitations and assumptions
No optical power penalty, calibrated BER or receiver-margin inference is supplied.
Numeric inputs, where present, must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.
Alternative or Complementary methods
Use Ffe Tap Weight Calculator: A finite causal zero-forcing FFE inverts the leading channel response. Truncation leaves a residual tail. For a complementary task, use Dfe Tap Weight Calculator: Ideal additive DFE weights cancel observed postcursor interference relative to a main cursor. Correct past decisions are assumed.
References
-
Eye Closure Penalty Calculator — tool.io
Similar or alternative tools
- Ffe Tap Weight Calculator
A finite causal zero-forcing FFE inverts the leading channel response. Truncation leaves a residual tail.
- Dfe Tap Weight Calculator
Ideal additive DFE weights cancel observed postcursor interference relative to a main cursor. Correct past decisions are assumed.