4 Channels Double Fiber Passive DWDM Line Termination Unit: DDLT-4
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DDLT-4-2124-31-M
4-Channel Double Fiber DWDM Line Termination Overview
The DDLT-4 is a passive, double fiber, one-sided DWDM line termination unit (OADM) built on thin-film filter (TFF) technology. It terminates 4 ITU-T G.694.1, 100 GHz DWDM channels at one end of the line, dropping them at the site where it is installed rather than passing them onward. The product is configurable: choose the DWDM channel group, mini-LGX or LGX housing, and an optional 1310nm window port.
- xWDM Technology: DWDM
- Number of Data Streams: 4
- Number of Optical Channels: 4
- Connector: LC/UPC
- Filter Technology: TFF (Thin Film Filter)
- Insertation Loss (Passband): 1.8 dB
- Operating Temperature: 0 °C - 70 °C
- MTBF: 1000000 hours
DDLT-4 Configurator & Pricing
Configure your product below — the price, SKU and images update with every choice.
Review your configuration
- Housing
- mini-LGX Type (-M)mini-LGX Type (-M)
- Channel (DWDM)
- Ch.21-Ch.24 (-2124)Ch.21-Ch.24 (-2124)
- Window Port
- YesYes
- EXP Expansion Port
- NoNo
- Window Port Insertion Loss
- 1.0 dB1.0 dB
- Added Passband Insertion Loss
- +0.3 dB+0.3 dB
DDLT-4 DWDM Line Termination Pricing
SKU:DDLT-4-2124-31-MDDLT-4-2124-31-M
Special Order - Up to 4 WeeksSpecial Order - Up to 4 Weeks4 Channels Double Fiber Passive DWDM Line Termination Unit Specification
Product Type | OADM Unit |
Number of Data Streams | 4 |
Number of Optical Channels | 4 |
Connector | LC/UPC |
Operating Wavelengths | 10 DWDM Channel groups Ch 21-60 (1560.61-1529.55nm) |
Channel Spacing | 100 GHz (0.8 nm) |
Passband | >0.22 nm |
Filter Technology | TFF (Thin Film Filter) |
Insertation Loss (Passband) | 1.8 dB |
Isolation Adjacent Channels | 30 dB |
Isolation Non-Adjacent Channels | 40 dB |
Channel Pass-band Ripple | 0.5 dB |
Polarization Dependent Loss (PDL) | 0.1 dB |
Polarization Mode Dispersion (PMD) | 0.1 ps |
Return Loss | 45 dB |
Maximum Power Handling | 500 mW |
Operating Temperature | 0 °C - 70 °C |
Operating Humidity | 5 % - 95 % |
Storage Temperature | -40 °C - 85 °C |
MTBF | 1000000 hours |
Compliance | CE, ISO, ITU-T G.694.1, RoHS |
4 Channels Double Fiber Passive DWDM Line Termination Unit Datasheet
v5Complete technical specifications and product details
4 Channels Double Fiber Passive DWDM Line Termination Unit Description
The DDLT-4 is a passive DWDM line termination unit built on thin-film filter (TFF) technology. It terminates 4 ITU-T G.694.1, 100 GHz DWDM channels over LC/UPC connectors at the site where it is installed. It needs no power and carries no protocol-specific circuitry, so it handles any traffic type on the wavelengths passing through it.
Each channel group is a fixed 4-channel band on the ITU-T G.694.1 grid, 100 GHz (0.8 nm) spacing, with a passband greater than 0.22 nm. Insertion loss is up to 1.8 dB on the passband and up to 1.5 dB on the express path without the window port, rising to up to 2.1 dB and up to 1.8 dB with it. Isolation is 25 dB adjacent and 35 dB non-adjacent, with 0.5 dB passband ripple, 0.1 dB PDL, 0.1 ps PMD and 45 dB return loss. Power handling is 500 mW max, operating range 0 to 70 C, MTBF 1,000,000 hours.
The DDLT-4 ships as a configurable product. Housing is mini-LGX for panel or splice-tray mounting, or LGX Type for a standard 19 inch LGX rack shelf such as the EdgeOptic LGX-RCK-2-1U. The DWDM channel group sets which of the ten fixed 4-channel bands across Ch.21-60 (1560.61 to 1529.55 nm) the unit terminates and must match the line's existing channel plan, since one unit covers one band, not the full range. The optional 1310nm window port adds a tap for line-signal monitoring, at the insertion-loss cost above. No expansion (EXP) port is offered on this line-termination unit; that connector exists on the mux/demux side of the xWDM family, not here.
As a 1-side unit, the DDLT-4 terminates drop channels only at its installation site and does not pass them onward, unlike the DDAD family of 2-sided add/drop units for mid-span insertion on both East and West line directions. The DDLT-4 is the 4-channel member of the DDLT line-termination series, alongside the DDAD 2-sided add/drop family.
The DDLT-4 is compliant with CE, ISO and RoHS, and meets ITU-T G.694.1 for the DWDM grid. For help matching the channel group to an existing DWDM plan or specifying housing for a particular rack layout, contact our sales team.
Frequently Asked Questions
Should I choose the mini-LGX or LGX Type housing?
Mini-LGX housing is sized for direct panel or splice-tray mounting where rack space is limited. LGX Type housing is sized for a standard 19 inch LGX rack shelf, such as the EdgeOptic LGX-RCK-2-1U, and fits a rack-and-shelf deployment better. The optical specifications are identical between the two housings; the choice is about how the unit gets mounted, not about performance.
How do I pick the right DWDM channel group, and what happens if it does not match my existing plan?
The DDLT-4 configurator offers ten fixed 4-channel bands spanning Ch.21-60 (1560.61 to 1529.55 nm) on the ITU-T G.694.1, 100 GHz grid. Each unit is built for one band only, not the full range, so the band selected has to match the channel plan already running on the DWDM line. If the network's existing plan uses a band outside the one ordered, the unit will not terminate those wavelengths. Verify the channel plan against the network's wavelength assignment before ordering.
What does the 1310nm window port do, and is the insertion loss cost worth it?
The 1310nm window port is a tap that lets a technician check the aggregated DWDM line signal power with a standard 1310nm-compatible power meter, without breaking the line to insert a meter inline. Adding it raises insertion loss from 1.8 dB to 2.1 dB on the passband channels and from 1.5 dB to 1.8 dB on the express channels. Whether that loss is acceptable depends on the link's overall optical budget; on links with margin to spare, the window port adds a useful field-serviceable check point.
What is the difference between the DDLT-4 and the DDAD family?
The DDLT-4 is a 1-side unit. It terminates its 4 drop channels only at the site where it is installed and does not pass them onward. The DDAD family is a 2-sided add/drop design that adds or drops channels on both the East and West line directions, built for mid-span insertion into a ring or linear DWDM network. Choose the DDLT-4 for a line-termination point at the end of a DWDM run, and the DDAD family for a site that needs to add or drop channels while passing the rest of the line through.
Is the DDLT-4 a DWDM or CWDM component?
The DDLT-4 is a DWDM unit built to the ITU-T G.694.1 DWDM grid with 100 GHz (0.8 nm) channel spacing, not the ITU-T G.694.2 CWDM grid. It is not interchangeable with CWDM mux/demux or CWDM line termination hardware; the channel plan, spacing and filter design are specific to the DWDM grid.