24-channel synchronous parallel optical fiber interconnection

The article describes the complete experimental demonstration of an optoelectronic parallel interconnection spanning 24 parallel channels comprising three units of hermetically packaged monolithic 8-element laser array, integrated 8-element fiber optical ribbon, and monolithic 8-element photodetector array, and the corresponding 24-channel electronic circuitry for drive and reception. The experimental system has a 300 m fiber length per channel. All channels are totally independent both electrically and optically. The measured optical crosstalk (XTK) is <-40 dB, and the thermal XTK is <-30 dB. The total skew is less than 5 ns; and the BER is <10^-14. Successful installation of the optical multichannel interconnection in a digital switching (Tropico RA) system demonstrated error-free operation and no degradation in performance, compared to the present (≈10 m cable length) standard electrical interconnection