Cable assembly increases Gigabit Ethernet reach

Edited by the Electronicstalk editorial team Jul 12, 2002

Tyco Electronics has an AMP Netconnect Gigabit Ethernet mode-conditioning cable assembly that has been approved by Cisco and given one of its part numbers.

Tyco Electronics has an AMP Netconnect Gigabit Ethernet mode-conditioning cable assembly that has been approved by Cisco and given one of its part numbers.

The new mode-conditioning assembly is designed for use in 62.5/125 multimode fibre-optic cabling systems, where these assemblies allow long-wavelength (1300nm) signals to be transmitted over good-quality fibre at distances of up to 550m.

The LX long-wavelength devices used in Gigabit Ethernet applications are based on a single-mode launch condition, and operate over both single-mode and multimode fibre.

Differential mode delay occurs when the transmitter device launches a single-mode laser signal into the centre of a multimode fibre, resulting in the transmission of multiple signals.

Such signals can confuse the receiver device, with resultant limitations on the operating bandwidth of Gigabit Ethernet.

The 62.5/125 fibre will typically only allow a distance of 220-270m for Gigabit Ethernet using lower-cost lasers operating at the 850nm (SX wavelength), and longer distance requirements have to be met by the use of 1300nm electronics in conjunction with a mode-conditioning launch lead.

The AMP Netconnect mode-conditioning cable assembly eliminates differential-mode delay by moving the single-mode launch to an offset position away from the centre of the fibre where most impurities are found.

The lead carries AMP Netconnect Part number 1536259-3 and Cisco Part Number 72-1517-01.