Nortel 1000 Manual

Also see for 1000 Con?guration guide: Brochure Reference User manual Overview User guide

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Engineering guidelines 35calculations must be made to determine the maximum link distance. Thedata rate over the multi-mode fiber is limited by the optical bandwidth ofthis multi-mode fiber. The bandwidth is defined as the frequency at whicha sinusoidal signal is attenuated by 3 dB relative to a DC signal.For the Fiber Remote IPE, the bandwidth is defined to be 1310nanometers. The bandwidth-length product for single-mode is 5 GHz kmand for the graded index multi-mode is 800 MHz km.When engineering a fiber-optic link, make sure that the total signalattenuation between the Fiber Superloop Network and the Fiber PeripheralController Electro-optical interfaces does not exceed 13 dB loss.Note: If the fiber-optic link already exists, check the link’s characteristicsand end-to-end loss to determine if it can support a Fiber Remote IPEand, if it can, at what distance between the local system and the FiberRemote IPE.Bandwidth engineering rulesThe eye closure due to dispersion must not exceed 0.5 dB to ensurereliable operation of the Electro-optical packlets. Based on this, thenormalized bandwidth (BN) must not be less than 0.71.The maximum fiber length for a link can be calculated by the followingequation, where L is the fiber-optic link length, B L is the bandwidth-lengthproduct, B T is the NRZ bit rate of 155.52 MHz, and B N is the maximumallowable optical bandwidth of 0.71 when normalized to the above bit rate.To engineer a multi-mode fiber link, follow the steps in Procedure 1“Engineering a multi-mode fiber link” (page 35).:Procedure 1Engineering a multi-mode fiber linkStep Action1 Obtain bandwidth-length product of the fiber from themanufacturers’ data sheet.2 Calculate the maximum link length using the above equation.3 Measure the eye closure of the fiber.When measured at 155.52 MHz and 1310 nanometers, it shouldbe less than 0.5 dB.4 Measure the attenuation of the fiber link.Nortel Communication Server 1000Fiber Remote IPE FundamentalsNN43021-554 04.01 4 June 2010Copyright © 2007-2010 Nortel Networks. All Rights Reserved.