公开(公告)号：CA2607317A1

公开(公告)日：2006-11-23

申请号：CA2607317

申请日：2006-04-25

Applicant: LUCENT TECHNOLOGIES INC

Inventor： GILES RANDY CLINTON ,  DORRER CHRISTOPHE J ,  DINU MIHAELA ,  MAROM DAN MARK ,  KANG INUK

IPC: H04L9/08

Abstract: A communication system adapted to use wavelength (frequency) division multiplexing for quantum-key distribution (QKD). In one embodiment, a communication system of the invention has a transmitter coupled to a receive r via a transmission link. The transmitter has (i) a first optical-frequency comb source (OFCS) adapted to generate a first plurality of uniformly spaced frequency components and (ii) a first multi-channel optical modulator adapte d to independently modulate each component of the first plurality to produce a quantum-information (QI) signal applied to the transmission link. The receiv er has (i) a second OFCS adapted to generate a second plurality of uniformly spaced frequency components and (ii) a second multi-channel optical modulato r adapted to independently modulate each component of the second plurality to produce a local- oscillator (LO) signal. Each of the first and second optica l- frequency comb sources is referenced to a frequency standard such that the frequency components generated by these comb sources have substantially the same frequencies. The receiver employs a multi channel homodyne detector adapted to process interference signals produced by combining the LO signal with the QI signal to ascertain quantum information carried by the QI signal .

公开(公告)号：CA2607318A1

公开(公告)日：2006-11-23

申请号：CA2607318

申请日：2006-04-25

Applicant: LUCENT TECHNOLOGIES INC

Inventor： DINU MIHAELA ,  DORRER CHRISTOPHE J ,  KANG INUK ,  MAROM DAN MARK ,  GILES RANDY CLINTON

IPC: H04L9/08

Abstract: A communication system adapted to use wavelength (frequency) division multiplexing for quantum-key distribution (QKD) and having a transmitter coupled to a receiver via a transmission link. In one embodiment, the receiv er is adapted to (i) phase- shift a local oscillator (LO) signal generated at t he receiver, (ii) combine the LO signal with a quantum-information (QI) signal received via the transmission link from the transmitter to produce interference signals, (iii) measure an intensity difference for these interference signals, and (iv) phase-lock the LO signal to the QI signal bas ed on the measurement result, hi one configuration, the QI signal has a plurali ty of pilot frequency components, each carrying a training signal, and a plurality of QKD frequency components, each carrying quantum key data. Advantageously, the system can maintain a phase lock for the QKD frequency components of the QI and LO signals, while the QKD frequency components of t he QI signal continuously carry quantum key data.

公开(公告)号：CA2381682A1

公开(公告)日：2002-11-23

申请号：CA2381682

申请日：2002-04-12

Applicant: LUCENT TECHNOLOGIES INC

Inventor： XU CHUNHUI ,  DINU MIHAELA ,  KNOX WAYNE HARVEY ,  STUART HOWARD ROY ,  GARCIA HERNANDO ,  KILPER DANIEL CHARLES

IPC: G02F3/00 ,  H04B10/02 ,  H04B10/08 ,  H04B10/20 ,  H04B17/00 ,  H04J14/02

Abstract: An optical performance monitor (OPM), e.g., for use in an optical network. T he OPM may be configured to characterize one or more impairments in an optical signal modulated with data. The OPM has an optical autocorrelator configured to sample the autocorrelati on function of the optical signal, e.g., using two-photon absorption. Autocorrelation points at various bit delays independently or in combination with average optical power may be used to detect and/or quantify one or more of the following: loss of data modulation, signal contrast, puls e broadening, peak power fluctuations, timing jitter, and deviations from the pseudo-random character of data. In addition, the OPM may be configured to perform Fourier transformation based on the autocorrelation points to obtain corresponding spectral components. The spectral components may be used to detect and/or quantify one or more of chromatic dispersion, polarization mode dispersion, and misalignment of a pulse carver and data modulator. The OPM m ay be further configured to generate feedback, e.g., to network operators to improve netwo rk performance.