Patent ID: 11863989
Assignee: AHP-TECH INC.
Field: Digital communication (Electrical engineering)
Classification: CPC H  G | IPC G  H

Claim 7:
8. The method for resisting quantum perturbation threats to quantum communication devices according to claim 6, wherein in order to facilitate estimating optical phases, the means of inverse QFT comprises:
a) deriving eigenvector |Ψ from a linear combination of wave functions simulated from a harmonic oscillator in an optical-resonant cavity, and letting the corresponding eigenvalue be e2πiθ where i is √{square root over (−1)}, so as to derive a unitary operator U that makes U|Ψ equal to e2πiθ|Ψ;
b) collaborating quantum-simulation logic circuits with the derived unitary operator U to perform controlled-unitary operations on n q-bits of a quantum communication device to derive a quantum state of, 1
      
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  ,, wherein |k means the k-th basis in binary expression, thereby the n q-bits as the input of the simulated quantum circuits will be part of phase information θ; and
c) in condition that the phase information is θ, storing the probability amplitude of the above derived quantum state into corresponding bases via leveraging inverse operation of Quantum Fourier Transform to derive a transformed state, and then measuring the transformed state for getting an original quantum signal where the measured θ implies the corresponding phase.