HIGH-DATA RATE PARALLEL-BIT OPTICAL DATA LINKS FOR COMPUTER NETWORKS

WAVELENGTH DIVISION MULTIPLEXERS (WDM) ARE BEING DEVELOPED FOR USE IN COMPUTER NETWORKS. IN THE SYSTEM UNDER STUDY, THE WDM TECHNIQUE IS USED FOR PARALLEL TRANSMISSION OF DATA;EACH BIT IS ENCODED WITH A DIFFERENT WAVELENGTH AND SENT THROUGH ONE TRANSMISSION PATH (I.E., A SINGLE OPTICAL FIBER DATA LINK). TIME DIVISION MULTIPLEXING IS USED TO SEND THE DATA SERIALLY BY BYTES. WDM IS ONE OF MANY TECHNIQUES USED TO ACHIEVE HIGH DATA RATES IN OPTICAL COMMUNICATION NETWORKS. OTHER TECHNIQUES, SUCH AS TIME DIVISION AND CODE DIVISION MULTIPLEXING, ARE LIMITED BY THE SPEED OF ELECTRONIC TRANSMITTERS TO DATA RATES 1 TO 10 GBIT/SEC. THEHIGH COST OF THESE TRANSMITTERS AND RECEIVERS PREVENTS THEIR WIDE USE IN COMPUTER COMMUNICATION. WDM SYSTEMS OFFERHIGH CONCURRENCY AND PERMIT HIGH DATA RATES WITHOUT THE USE OF HIGH SPEED ELECTRONICS. THEREFORE, THEY ARE WELL SUITED FOR USE IN COMPUTER COMMUNICATION NETWORKS. FOR EXAMPLE, A 16-BIT 100 MBIT/SEC SYSTEM CAN BE UPGRADED TO A 1.6 GBIT/SECSYSTEM USING THE WDM TECHNIQUE WITHOUT SIGNIFICANT MODIFICATION OF THE EXISTING SOFTWARE AND ELECTRONICS. WDMSARE BASED ON HIGHLY SELECTIVE WAVEGUIDE HOLOGRAMS IN SINGLE MODE, LOW LOSS GLASS WAVEGUIDES. BECAUSE OF THE LONG INTERACTION LENGTH OF WAVEGUIDE HOLOGRAMS, THE CHANNEL BANDWIDTH CAN BE <1 NM. WDMS HAVE COMPACT DIMENSIONS, ARE COMPATIBLE WITH SINGLE MODE OPTICAL FIBERS, AND HAVE HIGH OPTICAL EFFICIENCY. PHASE I OF THIS PROJECT INCLUDES (1) ANALYSIS OF A WDM TRANSMISSION SYSTEM BASED ON COMMONLY AVAILABLE OPTOELECTRONIC COMPONENTS AND WAVEGUIDE WDMS, (2) DESIGN OF AND DEMONSTRATION OF WAVEGUIDE WDMS AND FABRICATION ON GLASS WAVEGUIDES, AND (3) DEMONSTRATION OF A 1 GBIT/SEC DATA TRANSMISSION SYSTEM USING THE WAVEGUIDE WDMSAND FOUR 250 MBIT/SEC DRIVERS.