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DWDM/CWDM Wavelength ITU Channels Guide

Updated on May 4, 2023 by

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In the rapidly evolving field of optical communications, mastering wavelength management is crucial. This comprehensive guide provides the essential knowledge to navigate ITU channel grids, choose the right transceiver modules, and optimize your fiber optic network. Whether you are an experienced professional or a newcomer, this guide will help you fully leverage DWDM and CWDM technologies.

DWDM

CWDM

DWDM ITU Channels Overview

The DWDM region, as defined by the ITU G.694.1 standard, spans from 1528.77 nm to 1563.86 nm, mainly within the C band. DWDM channel plans may vary, but a common setup includes either 40 channels with 100 GHz (0.8 nm) spacing or 80 channels with 50 GHz (0.4 nm) spacing. Currently, DWDM systems operating within the 100 GHz DWDM C-Band typically follow a channel plan ranging from channels 17 to 61. For a more detailed overview, please refer to the DWDM Channel List below, which provides specific wavelengths and frequency intervals for each channel.

DWDM 100GHz ITU Grid

Channel	Frequency	Wavelength	Channel	Frequency	Wavelength
#	GHz	nm	#	GHz	nm
1	190100	1577.03	37	193700	1547.72
2	190200	1576.2	38	193800	1546.92
3	190300	1575.37	39	193900	1546.12
4	190400	1574.54	40	194000	1545.32
5	190500	1573.71	41	194100	1544.53
6	190600	1572.89	42	194200	1543.73
7	190700	1572.06	43	194300	1542.94
8	190800	1571.24	44	194400	1542.14
9	190900	1570.42	45	194500	1541.35
10	191000	1569.59	46	194600	1540.56
11	191100	1568.11	47	194700	1539.77
12	191200	1567.95	48	194800	1538.98
13	191300	1567.13	49	194900	1538.19
14	191400	1566.31	50	195000	1537.4
15	191500	1565.5	51	195100	1536.61
16	191600	1564.68	52	195200	1535.82
17	191700	1563.86	53	195300	1535.04
18	191800	1563.05	54	195400	1534.25
19	191900	1562.23	55	195500	1533.47
20	192000	1561.41	56	195600	1532.68
21	192100	1560.61	57	195700	1531.9
22	192200	1559.79	58	195800	1531.12
23	192300	1558.98	59	195900	1530.33
24	192400	1558.17	60	196000	1529.55
25	192500	1557.36	61	196100	1528.77
26	192600	1556.55	62	196200	1527.99
27	192700	1555.75	63	196300	1527.22
28	192800	1554.94	64	196400	1526.44
29	192900	1554.13	65	196500	1525.66
30	193000	1553.33	66	196600	1524.89
31	193100	1552.52	67	196700	1524.11
32	193200	1551.72	68	196800	1523.34
33	193300	1550.92	69	196900	1522.56
34	193400	1550.12	70	197000	1521.79
35	193500	1549.32	71	197100	1521.02
36	193600	1548.51	72	197200	1520.25

DWDM 50GHz ITU Grid

Channel	Frequency	Wavelength	Channel	Frequency	Wavelength
#	GHz	nm	#	GHz	nm
1	190.1	1577.03	37	193.7	1547.72
1.5	190.15	1576.61	37.5	193.75	1547.32
2	190.2	1576.2	38	193.8	1546.92
2.5	190.25	1575.78	38.5	193.85	1546,52
3	190.3	1575.37	39	193.9	1546,12
3.5	190.35	1574.95	39.5	193.95	1545.72
4	190.4	1574.54	40	194	1545.32
4.5	190.45	1574.13	40.5	194.05	1544.92
5	190.5	1573.71	41	194.1	1544.53
5.5	190.55	1573.3	41.5	194.15	1544.13
6	190.6	1572.89	42	194.2	1543.73
6.5	190.65	1572.48	42.5	194.25	1543.33
7	190.7	1572.06	43	194.3	1542.94
7.5	190.75	1571.65	43.5	194.35	1542.54
8	190.8	1571.24	44	194.4	1542.14
8.5	190.85	1570.83	44.5	194.45	1541.75
9	190.9	1570.42	45	194.5	1541.35
9.5	190.95	1570.01	45.5	194.55	1540.95
10	191	1569.59	46	194.6	1540.56
10.5	191.05	1569.18	46.5	194.65	1540.16
11	191.1	1568.11	47	194.7	1539.77
11.5	191.15	1568.36	47.5	194.75	1539.37
12	191.2	1567.95	48	194.8	1538.98
12.5	191.25	1567.54	48.5	194.85	1538.58
13	191.3	1567.13	49	194.9	1538.19
13.5	191.35	1566.72	49.5	194.95	1537.79
14	191.4	1566.31	50	195	1537.4
14.5	191.45	1565.9	50.5	195.05	1537
15	191.5	1565.5	51	195.1	1536.61
15.5	191.55	1565.09	51.5	195.15	1536.22
16	191.6	1564.68	52	195.2	1535.82
16.5	191.65	1564.27	52.5	195.25	1535.43
17	191.7	1563.86	53	195.3	1535.04
17.5	191.75	1563.45	53.5	195.35	1534.64
18	191.8	1563.05	54	195.4	1534.25
18.5	191.85	1562.64	54.5	195.45	1533.86
19	191.9	1562.23	55	195.5	1533.47
19.5	191.95	1561.83	55.5	195.55	1533.07
20	192	1561.42	56	195.6	1532.68
20.5	192.05	1561.01	56.5	195.65	1532.29
21	192.1	1560.61	57	195.7	1531.9
21.5	192.15	1560.2	57.5	195.75	1531.51
22	192.2	1559.79	58	195.8	1531.12
22.5	192.25	1559.39	58.5	195.85	1530.72
23	192.3	1558.98	59	195.9	1530.33
23.5	192.35	1558.58	59.5	195.95	1529.94
24	192.4	1558.17	60	196	1529.55
24.5	192.45	1557.77	60.5	196.05	1529.16
25	192.5	1557.36	61	196.1	1528.77
25.5	192.55	1556.96	61.5	196.15	1528.38
26	192.6	1556.56	62	196.2	1527.99
26.5	192.65	1556.15	62.5	196.25	1527.6
27	192.7	1555.75	63	196.3	1527.22
27.5	192.75	1555.34	63.5	196.35	1526.83
28	192.8	1554.94	64	196.4	1526.44
28.5	192.85	1554.54	64.5	196.45	1526.05
29	192.9	1554.13	65	196.5	1525.66
29.5	192.95	1553.73	65.5	196.55	1525.27
30	193	1553.33	66	196.6	1524.89
30.5	193.05	1552.93	66.5	196.65	1524.5
31	193.1	1552.52	67	196.7	1524.11
31.5	193.15	1552.12	67.5	196.75	1523.72
32	193.2	1551.72	68	196.8	1523.34
32.5	193.25	1551.32	68.5	196.85	1522.95
33	193.3	1550.92	69	196.9	1522.56
33.5	193.35	1550.52	69.5	196.95	1522.18
34	193.4	1550.12	70	197	1521.79
34.5	193.45	1549.72	70.5	197.05	1521.4
35	193.5	1549.32	71	197.1	1521.02
35.5	193.55	1548.91	71.5	197.15	1520.63
36	193.6	1548.52	72	197.2	1520.25
36.5	193.65	1548.11	72.5	197.25	1519.86

FS DWDM Transceiver Modules Quick View

FS DWDM transceivers are available with C17-C61 100 GHz DWDM wavelengths, and C17-C61 50 Ghz DWDM wavelengths, including DWDM SFP, DWDM SFP+, DWDM XFP, and Tunable DWDM transceivers that support transmission distance up to 100 km. Tunable DWDM transceivers are able to support a specific channel in a DWDM optical network, allowing for remotely wavelengths change in software.

FS DWDM Mux/Demux

DWDM Mux/Demux is made to multiplex and demultiplex multiple DWDM channels into one or two fibers. It can extend the bandwidth of optical communication network with low cost and long transmission distance up to 1000 kilometers, which makes it an ideal long-haul network solution. FS offers DWDM Mux/Demux in different channal numbers and single or dual fiber types.

Product Description	Line Type	Wavelength	Channel Spacing (GHz)
8CH DWDM Mux/Demux	Dual Fiber	C21-C28, C53-C60	100
8CH DWDM Mux/Demux	Single Fiber	C21-C35, C22-C36	100
16CH DWDM Mux/Demux	Dual Fiber	C17-C32, C21-C36, C27-C42, C43-C58	100
40CH DWDM Mux/Demux	Dual Fiber	C21-C60	100
96CH DWDM Mux/Demux	Dual Fiber	C15-C62.5	50

CWDM ITU Channels Overview

ITU-T G.694.2 defines 18 wavelengths for CWDM transport ranging from 1270 to 1610 nm, spaced at 20 nm apart. The complete CWDM ITU grid is shown below in the CWDM channel chart. Each CWDM channel is transparent to the speed and type of data, meaning that any mix of SAN, WAN, voice, and video services can be transported simultaneously over a single fiber or fiber pair.

CWDM Channels
ITU Channel No.	Wavelength (nm)	Latch Color by Wavelength
27	1270
29	1290
31	1310
33	1330
35	1350
37	1370
39	1390
41	1410
43	1430
45	1450
47	1470
49	1490
51	1510
53	1530
55	1550
57	1570
59	1590
61	1610

FS CWDM Transceiver Modules Quick View

FS CWDM transceivers are available with all 18 CWDM wavelengths, including CWDM SFP, CWDM SFP+, CWDM XFP and 3G SDI CWDM SFP modules. These CWDM transceivers can be applied in data transmission spanning 20 km to 120 km.

20KM CWDM Modules

CWDM SFP 20KM

CWDM SFP+ 20KM

CWDM XFP 20KM

40KM CWDM Modules

80KM CWDM Modules

CWDM SFP 80KM

CWDM SFP+ 80KM

CWDM XFP 80KM

120KM CWDM Modules

CWDM SFP 120KM

FS CWDM Mux/Demux

In addition to the various CWDM transceivers, FS also provides a wide range of CWDM Mux/Demux, which acts as the major building block in network expansion and upgrade. FS CWDM Mux/Demux comes in several different types in regard to line type, channel number, and special port.

Product Description	Line Type	Wavelength
4CH CWDM Mux/Demux	Dual Fiber	1270-1330nm, 1510-1570nm
4CH CWDM Mux/Demux	Single Fiber	1470-1590nm, 1490-1610nm
8CH CWDM Mux/Demux	Dual Fiber	1290-1430nm, 1430-1570nm, 1470-1610nm, 1270-1450nm (Skip 1390, 1410nm)
9CH CWDM Mux/Demux	Single Fiber	1270-1590nm, 1270-1610nm, 1290-1610nm
18CH CWDM Mux/Demux	Dual Fiber	1270-1610nm

FAQs about DWDM/CWDM Wavelength Channels

Q1: How Does the Scalability Potential of DWDM and CWDM Differ?

CWDM offers support for 18 channels, making it suitable for moderate bandwidth over shorter distances. On the other hand, DWDM provides high scalability with 96 channels, owing to its finer channel spacing and broader wavelength range, thus catering to large-scale networks with high bandwidth demands and longer transmission distances.

Q2: When Considering Between DWDM/CWDM and Deploying More Fibers, What Factors Should Be Weighed?

The optimal choice depends on project-specific needs. While deploying more fibers may seem simpler, it comes with limitations on scalability and physical space. Conversely, DWDM/CWDM offers scalability and more efficient utilization of fiber resources.

Q3: What Are the Advantages of Single vs. Dual Fiber Passive Setups in DWDM or CWDM Systems?

Dual fiber setups typically offer twice as many channels compared to single fiber setups, making them a preferred choice. However, single fiber configurations may be considered if there are constraints on fiber availability.

Q4: How Do the 10 G, 25 G, and 100 G Solutions for Long-Distance Traffic in DWDM/CWDM Networks Differ?

The choice between 10 G, 25 G, and 100 G solutions depends on bandwidth requirements, scalability, and the availability of transceivers capable of reaching desired distances. For instance, while 10 G setups are suitable for distances up to about 80 km, 25 G solutions can reach 20-30 km, albeit with limited availability for longer distances. Meanwhile, 100 G passive setups are feasible within specific ranges and may require amplification techniques for longer distances.

Conclusion

DWDM and CWDM technologies are indispensable for expanding fiber optic networks, efficiently meeting the escalating demands of data transmission while maximizing existing infrastructure. This article comprehensively covers ITU channel grids, optical transceiver modules, transmission distances, and multiplexing/demultiplexing products provided by FS. Additionally, it includes detailed information about the ITU channel list. These advancements not only enhance network bandwidth and extend transmission ranges but also drive down operational costs. Whether establishing long-haul backbone networks or optimizing metropolitan area networks (MAN), the selection of the appropriate DWDM or CWDM solution significantly influences performance and scalability. We strive for this guide to provide invaluable insights and guidance for navigating complex fiber optic environments successfully. Should you require further technical support or have inquiries, please don't hesitate to contact our expert team.

Related Articles:

CWDM (Coarse Wavelength Division Multiplexing)

DWDM (Dense Wavelength Division Multiplexing)

CWDM vs DWDM