AIRCRAFT BUILT-IN TEST WITH HIGHLY FAULT TOLERANT/ROBUST FIBER OPTIC VARIABLE-CHANNEL COMMUNICATION SYSTEM

FAILURE PREDICTION AND FAILURE ISOLATION IN FIBER OPTIC SYSTEMS ARE OF EXTREME IMPORTANCE IN AIRCRAFT, WHERE A DELAY OF MICROSECONDS IN CONVEYING A WARNING OF FAILURE MAY CAUSE CRITICAL LOSS. EXISTING SYSTEMS ATTEMPT TO ADDRESS THIS PROBLEM BY USING CONVENTIONAL TECHNIQUES SUCH AS ERROR CORRECTION CODING, SERIAL CONTROL INSERTIONS, BLOCK PREOR POST-AMBLES... . THESE APPROACHES SACRIFICE CRITICAL SPEED, RESULT IN LOSS OF MODULARITY, AND HAVE PROBLEMS OF INTERFACE COMPONENT RELIABILITY. THE RESULT IS A SIGNIFICANT LOSS IN EFFICIENCY AND INCREASE IN COST. OPTICAL COMMUNICATIONS CORPORATION (OCC) PROPOSES A FIBER OPTIC INNOVATIVE SYSTEM, ELEGANT IN ITS SIMPLICITY, SOLVING THE RELIABILITY PROBLEMS, WHILE BEING COMPLETELY COMPATIBLE WITH EXISTING STANDARDS. THE BUILT-IN-TET (BIT) CIRCUITRY OF THE PROPOSED SYSTEM ENCOMPASSES AN ERROR DETECTION CODE OVERLAYING EACH BIT, AND IT HAS AN ABILITY TO DELIVER SELF-TEST INFORMATION QUICKLY TO THE NEXT CHANNE IN-BAND. THE BIT ERROR RATE (BER) OF THE SYSTEM IS REDUCED SIGNIFICANTLY. ADDITIONALLY, THE SYSTEM CAN OVERCOME A CATASTROPHIC FAILURE WITHOUT BECOMING INOPERATIVE, AND USERS AT THE FAR END CAN BE NOTIFIED CONCURRENTLY WITH RECEIPT OF THE DATA ITSELF.