| 摘要 |
<p>AN APPARATUS AND METHOD (100) FOR DUAL CODING COHERENT PHASE PROTOCOL IN QUANTUM KEY DISTRIBUTION (QKD) SYSTEM USING A COHERENT LASER SOURCE (102), AN INTENSITY MODULATOR (103) AND A PHASE MODULATOR (105) IS DISCLOSED. THE SYSTEM COMPRISES TWO LEVELS OF ENCODING AND SIX TYPES OF DECOY BITS TO FURTHER IMPROVE SECURITY OF THE SECRET KEYS. THE SYSTEM COMPRISES AN INTENSITY MODULATOR FOR INTENSITY CODING WHEREIN A SECRET KEY IS CODED, MEANS TO GENERATE A TRAIN OF PULSES WITH BITS ?1? FOR WEAK COHERENCE PULSE (WCP AND BITS ?0? FOR VACUUM PULSE; AND A PHASE MODULATOR FOR DIFFERENTIAL PHASE CODING COMPRISES THE INTENSITY CODED SECRET KEY FURTHER CODED WITH BITS ?1? FOR PHASE DIFFERENCE OF 0; BITS ?0? FOR PHASE DIFFERENCE OF ? FOR WEAK COHERENCE PULSE (WCP); AND DECOY BITS FOR OTHER ORIENTATION PHASE DIFFERENCE OF VACUUM PULSE AND WCP.</p> |
