Nortel Networks 450 manual Table B-6 1000BASE-LX Transmit Characteristics, Description Value Units

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