Single-port, high-speed OC-12 OLIU (LNW48, LNW50, LNW54)

Optical specification for LNW48

The LNW48 optics meet or exceed SONET OC-12 intermediate-reach specifications (SONET OC-12 IR-1). The multi-longitudinal-mode/Fabry-Perot (FP) laser supplies a 1310 nm, scrambled NRZ-coded signal (622.08 Mb/s).

The LNW48 high-speed interface supports span lengths up to 20 km and is OSP hardened.

Optical specification for LNW50

The LNW50 optics meet or exceed SONET OC-12 long-reach specifications (SONET OC-12 LR-1). The single-longitudinal-mode/distributed feedback laser (DFB) supplies a 1310 nm, scrambled NRZ-coded signal (622.08 Mb/s).

The LNW50 high-speed interface supports span lengths up to 53 km and is OSP hardened.

Optical specification for LNW54

The LNW54 optics meet or exceed SONET OC-12 long-reach specifications (SONET OC-12 LR-2). The single-longitudinal-mode/distributed feedback laser (DFB) supplies a 1550 nm, scrambled NRZ-coded signal (622.08 Mb/s).

The LNW54 high-speed interface supports span lengths up to 81 km and is OSP hardened.

System specifications

The table below lists the LNW48, LNW50, and LNW54 OC-12 system specifications.

Table 10-13: LNW48, LNW50, and LNW54 optical system specifications

System information	LNW48	LNW50	LNW54
Optical Line Rate	622.08 Mb/s
Optical Line Coding	Scrambled NRZ
Optical Wavelength	1310 nm		1550 nm
Performance	SONET OC-12, Intermediate Reach IR-1	SONET OC-12 Long Reach, LR-1	SONET OC-12 Very Long Reach, LR-2
Temperature Range	OSP hardened/Industrial (−40°C to 85°C)

Transmitter specifications

The table below lists the LNW48, LNW50, and LNW54 OC-12 transmitter information.

Table 10-14: LNW48, LNW50, and LNW54 optical transmitter information

Transmitter information	LNW48	LNW50
Optical Device Temperature Controller	None
IEC 60825 Laser Classification	Class 1
FDA Laser Classification	Class I
Optical Source	Fabry Perot (FP) Laser	Distributed Feed-Back (DFB) Laser
Faceplate Optical Connector	LC connector

Receiver specifications

The table below lists the LNW48, LNW50, and LNW54 OC-12 receiver information.

Table 10-15: LNW48, LNW50, and LNW54 optical receiver information

Receiver information	LNW48, LNW50, LNW54
Optical Detector	InGaAsP PIN
Faceplate Optical Connector	LC connector

Receiver

information

LNW48, LNW50, LNW54

Optical Detector

InGaAsP PIN

Faceplate Optical Connector

LC connector

Link budgets

The table below lists the LNW48, LNW50, and LNW54 link budgets.

Table 10-16: LNW48, LNW50, and LNW54 optical specifications and link budgets

Parameter	LNW48 OC-12 IR-1¹	LNW50 OC-12 LR-1¹	LNW54 OC-12 LR-2¹
Minimum Wavelength	1274 nm	1280 nm	1480 nm
Maximum Wavelength	1356 nm	1335 nm	1580 nm
Maximum Spectral Width (Δλ₂₀)	NA	1.0 nm	1.0 nm
Maximum RMS Spectral Width (σ)	2.5 nm	NA	NA
Minimum Side Mode Suppression Ratio	NA	30.0 dB	30.0 dB
Maximum Transmitter Power	−8.0 dBm	2.0 dBm	2.0 dBm
Minimum Transmitter Power	−15.0 dBm	−2.5 dBm	−3.0 dBm
Maximum Received Power	−8.0 dBm	−7.0 dBm	−8.0 dBm
Minimum Received Power (1x10⁻¹² BER)	−28.0 dBm	−30.5 dBm	−29.0 dBm
System Gain²	13.0 dB	28.0 dB	26.0 dB
Optical Path Penalty³	1.0 dB	1.0 dB	1.0 dB
Minimum Optical Return Loss⁴	NA	20.0 dB	24.0 dB
Maximum Receiver Reflectance⁴	NA	−14.0 dB	−27.0 dB
Additional Connector Loss Margin⁵	1.5 dB	1.5 dB	1.5 dB
Additional Unallocated Margin⁶	1.5 dB	1.5 dB	1.5 dB
Minimum Loss Budget⁷	0.0 dB	9.0 dB	10.0 dB
Maximum Loss Budget⁸	9.0 dB	24.0 dB	22.0 dB
Approximate Span Length⁹	20 km	53 km	81 km

Notes:

All terminology is consistent with GR-253-CORE, Issue 3. All values are worst-case end of life.
The System Gain includes connector loss at the transmitter and receiver points S and R in GR-253-CORE, Issue 3.
Optical path penalty includes effects of dispersion, reflection, and jitter that occur on the optical path. At OC-12 rates, the optical path penalty is normally 1.0 dB for both 1310 nm and 1550 nm optics.
Refer to GR-253-CORE for more information about these parameters.
One additional connector (0.75 dB) on each end is assumed to connect station cable to outside plant.
Additional unallocated margin, or safety margin, can be 0−3 dB. Typically, a 1.5 dB value is assumed.
For all packs and PTMs where the Minimum Loss Budget (MLB) is 0, no attenuator is required for loopbacks. For all packs and PTMs where the MLB is greater than 0, an attenuator is required. The value of the LBO must be equal to or greater than the MLB.
The stated maximum loss budget equals the System Gain, less the Optical Path Penalty, the Additional Connector Loss Margin, and the Additional Unallocated Margin. The resultant Maximum Loss Budget is available for station cable loss, transmission cable loss, and splice loss.
The Approximate Span Length values are calculated per an attenuation assumption. As a general rule, for attenuation-limited systems, an attenuation of 0.45 dB/km is used for 1310 nm optics. This estimate includes typical cable loss (0.40 dB/km) and up to 11 splice losses (0.2 dB per splice). For 1550 nm optics, an attenuation of 0.27 dB/km is used. Again, appropriate fiber-cable loss and numerous splice losses are included. For 1310 nm OC-3 and OC-12 systems, dispersion is not a limiting factor, and the applications are attenuation-limited. Approximate span lengths can be calculated more precisely based on particular fiber and splice characteristics and local engineering rules.

Alarm thresholding

The following parameters are monitored at the OC-12 high-speed (network-side) interface.

LOF
LOS
AIS-L
RFI-L (FERF)
Signal Degrade (BER)
Signal Fail (BER)

Performance monitoring

SONET line and path performance monitoring complies with the standards outlined in GR-253-CORE. For detailed PM parameter thresholds on the OC-12 high-speed interface, see Performance monitoring.