Gigabit Fiber Optical Characteristics

Transmit Characteristics

Table B-6 lists the transmit characteristics for the 1000BASE-LX models:

Table B-6.

1000BASE-LX Transmit Characteristics

 

 

 

 

 

 

 

 

 

 

 

 

10 Micron

 

 

 

62.5 Micron

50 Micron

Single-Mode

 

Description

 

Multimode Fiber

Multimode Fiber

Fiber

Unit

 

 

 

 

 

 

Transmitter type

 

Longwave Laser

Longwave Laser

Longwave Laser

 

Signaling speed (range)

1.25 ± 100 ppm

1.25 ± 100 ppm

1.25 ± 100 ppm

GBd

Wavelength (range)

1270 to 1355

1270 to 1355

1270 to 1355

nm

T rise /T fall

 

0.26

0.26

0.26

ns

(maximum 20-80% response time)

 

 

 

 

RMS spectral width (maximum)

4

4

4

nm

Average launch power (maximum)

– 3

– 3

– 3

dBm

Average launch power (minimum)

– 11.5

– 11.5

– 11.0

dBm

Average launch power of OFF

– 30

– 30

– 30

dBm

transmitter (maximum)

 

 

 

 

Extinction ratio (minimum)

9

9

9

dB

RIN (maximum)

 

– 120

– 120

– 120

dB/Hz

Coupled Power Ratio (CPR)1

28 < CPR < 40

12 < CPR < 20

N/A

dB

 

 

 

 

 

 

1Due to the dual media (single-mode and multimode) support of the LX transmitter, fulfillment of this specification requires a single-mode fiber offset-launchmode-conditioning patch cord described in IEEE 802.3, Clause 38.11.4 for MMF operation. This patch cord is not used for single-mode operation.

Receive Characteristics

Table B-7 lists the receive characteristics for the 1000BASE-LX models:

Table B-7.

1000BASE-LX Receive Characteristics

 

 

 

 

 

 

 

 

Description

 

Value

Units

 

 

 

 

Signaling speed (range)

1.25 ± 100 ppm

GBd

Wavelength (range)

1270 to 1355

nm

Average receive power (maximum)

– 3

dBm

 

 

 

(continued)

 

 

 

 

 

302401-D Rev 00

 

 

B-5

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Image 245
Nortel Networks 450 manual Table B-6 1000BASE-LX Transmit Characteristics, Table B-7 1000BASE-LX Receive Characteristics