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Calcimator

WDM Channel Spacing Calculator

Calculate wavelength division multiplexing channel count, spacing, and aggregate bandwidth for CWDM and DWDM systems.

Inputs

Gbps

Results

Usable Channels

8

Total Bandwidth

80 Gbps

Channel Spacing0.8 nm
Channel Spacing100 GHz
Spectrum Used6.4 nm
Remaining Channels36
MUX + DEMUX Loss7 dB
Channels Fit (1=Yes)1
Cost Per Gbps$3.75
How to Use This Calculator
  1. Select WDM Type: CWDM (20nm spacing, up to 18 channels) or DWDM at 100GHz, 50GHz, or 25GHz spacing (up to 44, 88, or 160 channels respectively).
  2. Enter Channels Needed and Data Rate per Channel (Gbps) for your capacity requirement.
  3. Set Fiber Pairs available in your cable plant.
  4. Review Usable Channels, Total Bandwidth (Gbps), Channel Spacing (nm and GHz), and Spectrum Used.
  5. Check Channels Fit (1=Yes) and MUX + DEMUX Loss (dB) — add this to your optical power budget calculation.

How the result changes with Channels Needed

Channels NeededUsable ChannelsTotal Bandwidth
2121210 Gbps
7144440 Gbps
13044440 Gbps
18044440 Gbps

What each input means

WDM Type
1=CWDM (20nm), 2=DWDM 100GHz (0.8nm), 3=DWDM 50GHz, 4=DWDM 25GHz
Channels Needed
Number of wavelength channels required
Data Rate per Channel
Data rate on each wavelength channel (10G, 25G, 40G, 100G, 400G)
Fiber Pairs
Number of fiber pairs carrying WDM signals

How this is calculated

Formula

Total BW = Channels × Rate/Channel × Fiber Pairs

Worked example, using the default values

  1. Identify Input Parameters
    4 parameters
    WDM Type = 2, Channels Needed = 8, Data Rate per Channel = 10, Fiber Pairs = 1 = 4 input(s) provided
  2. Calculate Usable Channels
    Usable Channels
    8 = 8
  3. Calculate Total Bandwidth
    Total Bandwidth
    80 = 80
  4. Calculate Channel Spacing
    Channel Spacing = 20
    0.8 = 0.8
  5. Calculate Channel Spacing
    Channel Spacing = 2500
    100 = 100

Engine last updated . Checked against 5 independently-derived tests — how we verify calculators.

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