HCS fiber based optical star net for automotive applications

Since 1998 the first optical data buses, based on a ring topology and polymethylmethacrylate (PMMA) fibers with 1 mm core diameter and red emitting LEDs were introduced in cars to interconnect information and entertainment components. These systems currently are limited to the passenger compartment, because PMMA fibers do not tolerate environmental temperatures above 85 °C, the data rate of these systems is limited to well below 100 MBit/s and the ring topology does not allow the interconnection of safety critical control units. Optical datacom buses based on standard multimode fibers are not useable in cars because of the severe environmental conditions and because of the extremely low-cost demands for in car data transmission systems. We propose and demonstrate a star coupled data bus system based on 200 μm core diameter hard clad silica (HCS) fibers for 16 terminals with a data rate of up to 200 MBit/s