FAST BIT-ERROR RATE CALCULATION MODE FOR QKD SYSTEMS

摘要

A fast bit-error rate (F-BER) calculation mode for a QKD system is disclosed, wherein the method includes establishing versions of a sifted key in respective sifted-bits (SB) buffers in respective QKD stations (Alice and Bob). The method also includes sending Alice's version of the sifted key to Bob, and Bob performing a comparison of the two sifted key versions. The number of bit errors between the two sifted key versions relative to the length of the sifted key yields the F-BER. The F-BER is calculated much more quickly than the conventional BER calculation (“N-BER”), which involves performing a relatively complex error-correction algorithm. The F-BER calculation mode is particularly useful in quickly setting up and/or calibrating a QKD system, and can be repeated quickly to provide updated BER measurements after each QKD system adjustment.