2 Systems with Wavelength Division Multiplexing - CWDM and DWDM grid
2.2 CWDM and DsWDM grid
Grid spacing in CWDM and DWDM systems

Technology

CWDM

DWDM – regional networks

DWDM – long-distance networks

Number of channels (wavelengths)

4-16

32-80

80-160

Bands

O, E, S, C, L

C, L

C, L, S

Channel spacing

20 nm or more (2500 GHz or more)

0.8 nm, 100 GHz

0.4 nm or less – 0.2 nm or 0.1 nm, (50 GHz or less)

Transmission capacity per channel

1.5 Gbps

10 Gbps

10-40 Gbps

Fibre capacity

20-40 Gbps

100-1000 Gbps

Tens of Tbps

Laser type

Non-cooled DFB or FP

Cooled DFB

Cooled DFB

Reach

50-80 km

100 km

1000 km

Price

Low

High

Highest

image
CWDM and DWDM operating wavelengths (exemplary).