Patent attributes
A system and a receiver for generating quantum key(s) using conjugated homodyne detection is provided. The receiver may communicate with a transmitter via an insecure quantum channel and a classical channel to generate the quantum key(s). A decoder, in the receiver, may determine, based at least in part on quadratures X, P measured by conjugated homodyne detectors, a raw-key signal corresponding to a key signal generated by the transmitter, and a distribution of photon numbers corresponding to a quantum signal received via the insecure quantum channel. Information about the key signal is exchanged between the receiver and the transmitter via the classical channel and used to determine a quantum bit error rate of the determined raw-key signal. A gain is also obtained. A secure-key rate is calculated based at least in part on the gain, the quantum bit error rate, and the photon number distribution.
