THE FEUTEX TOOLKIT

FM Carson Bandwidth

Estimate occupied analog-FM bandwidth and modulation index.

Communications workspace● Runs in your browser

01 Your input

Peak frequency deviationHzHighest modulation frequencyHz

02 Your result

View or copy raw result data

Result data

Formulaβ=Δf/fm; B≈2(Δf+fm)

Sources and model references

https://redbookdev.ntia.gov/view/J-19

Worked example

Inputs

Peak frequency deviation: 75000 Hz
Highest modulation frequency: 15000 Hz

Expected results

Modulation index: 5 ratio
Carson bandwidth: 180000 Hz

Load the example in the workspace to reproduce these results. Display rounding does not change the underlying calculation.

How to use this tool

Enter the labeled inputs in the indicated units.
Calculate and compare every output against the stated model assumptions.

Try this example

{
  "deviation": 75000,
  "audio": 15000
}

Accuracy and scope

Carson estimate for analog FM, not a spectrum mask or channel authorization. Simplified analytical model; not a design recommendation or safety certification.

Is my data uploaded?

This tool runs locally in your browser. Input and output are not sent to a processing server. Copy or download your result before leaving the page.