Patent classifications
H04B10/2513
Electronic access control based on optical codes
Methods and systems relating to administration of authentication information for electronic access control are disclosed. Authentication information is conveyed to an electronic locking device configured to restrict access to an entry point. In various embodiments, a smart device comprises a display screen for presenting a machine-readable optical code comprising encoded authentication information. An image sensor of the electronic locking device can decode the machine-readable optical code to obtain the authentication information. The electronic locking device is configured to permit access to the entry point in response to the image sensor detecting a machine-readable optical code corresponding to an access credential. A server device can provide authentication information to the smart device based on an access criterion. Conveying authentication information to the locking device may include rendering a webpage comprising the machine-readable optical code corresponding to the access credential.
Electronic access control based on optical codes
Methods and systems relating to administration of authentication information for electronic access control are disclosed. Authentication information is conveyed to an electronic locking device configured to restrict access to an entry point. In various embodiments, a smart device comprises a display screen for presenting a machine-readable optical code comprising encoded authentication information. An image sensor of the electronic locking device can decode the machine-readable optical code to obtain the authentication information. The electronic locking device is configured to permit access to the entry point in response to the image sensor detecting a machine-readable optical code corresponding to an access credential. A server device can provide authentication information to the smart device based on an access criterion. Conveying authentication information to the locking device may include rendering a webpage comprising the machine-readable optical code corresponding to the access credential.
Optical dispersion compensator on silicon
An optical dispersion compensator integrated with a silicon photonics system including a first phase-shifter coupled to a second phase-shifter in parallel on the silicon substrate characterized in an athermal condition. The dispersion compensator further includes a third phase-shifter on the silicon substrate to the first phase-shifter and the second phase-shifter through two 2×2 splitters to form an optical loop. A second entry port of a first 2×2 splitter is for coupling with an input fiber and a second exit port of a second 2×2 splitter is for coupling with an output fiber. The optical loop is characterized by a total phase delay tunable via each of the first phase-shifter, the second phase-shifter, and the third phase-shifter such that a normal dispersion (>0) at a certain wavelength in the input fiber is substantially compensated and independent of temperature.
APPARATUS AND METHOD FOR ANALOG ELECTRONIC FIBER DISPERSION AND BANDWIDTH PRE-COMPENSATION (EDPC) FOR USE IN 50 GBPS AND GREATER PAMN OPTICAL TRANSCEIVERS
Cost-effective high-data-rate optical data transceivers are presented, comprising an electronic analog transversal filter simultaneously providing one or more of bandwidth compensation and forward impairment compensations for the transmitted optical signal.
Frequency chirp correction method for photonic time-stretch system
A frequency chirp correction method for the photonic time-stretch system comprises acquiring the stretching signal, i.e. acquiring the time-domain data after the time-domain stretching. First, the time-domain data of the stretching signal is Fourier transformed to obtain the spectral distribution. The spectral distribution is then convoluted with the first frequency-domain correction factor, and then multiplied with the second frequency-domain correction factor to obtain the modified frequency spectrum. Finally, the modified frequency spectrum is performed by the inverse Fourier transform to obtain the time-domain signal after the frequency chirp correction.
Frequency chirp correction method for photonic time-stretch system
A frequency chirp correction method for the photonic time-stretch system comprises acquiring the stretching signal, i.e. acquiring the time-domain data after the time-domain stretching. First, the time-domain data of the stretching signal is Fourier transformed to obtain the spectral distribution. The spectral distribution is then convoluted with the first frequency-domain correction factor, and then multiplied with the second frequency-domain correction factor to obtain the modified frequency spectrum. Finally, the modified frequency spectrum is performed by the inverse Fourier transform to obtain the time-domain signal after the frequency chirp correction.
ENHANCEMENT OF OPTICAL COMMUNICATIONS AND OPTICAL FIBER PERFORMANCE
Communication of light signals and optical cables can be managed to mitigate error associated with using optical cables to communicate light signals. A communication management component (CMC) can embed respective timing synchronization pulses in respective lights signals having respective wavelengths. The light signals can be typical light signals or can be squeezed and twisted to generate a desired twisted light signal. The light signals can be transmitted via the optical cable to a receiver. A CMC, at the receiver end, can determine error associated with the transmission of the light signals via the optical cable and respective characteristics of the respective light signals, including respective arrival times of the respective timing synchronization pulses and respective light intensity or power levels of the respective light signals. From the respective characteristics, CMC can determine a compensation action to perform mitigate the error with regard to subsequent transmissions of light signals.
ENHANCEMENT OF OPTICAL COMMUNICATIONS AND OPTICAL FIBER PERFORMANCE
Communication of light signals and optical cables can be managed to mitigate error associated with using optical cables to communicate light signals. A communication management component (CMC) can embed respective timing synchronization pulses in respective lights signals having respective wavelengths. The light signals can be typical light signals or can be squeezed and twisted to generate a desired twisted light signal. The light signals can be transmitted via the optical cable to a receiver. A CMC, at the receiver end, can determine error associated with the transmission of the light signals via the optical cable and respective characteristics of the respective light signals, including respective arrival times of the respective timing synchronization pulses and respective light intensity or power levels of the respective light signals. From the respective characteristics, CMC can determine a compensation action to perform mitigate the error with regard to subsequent transmissions of light signals.
Device and system for coherently recombining multi-wavelength optical beams
An elementary device for coherently recombining a first elementary beam and a second elementary beam, includes a first input and a second input, into which are respectively injected the first elementary beam and the second elementary beam to be recombined, an output that delivers an output beam corresponding to the coherent recombination of the first and second elementary beams, a delay line placed on one of the paths of said elementary beams and configured to induce a variable delay on said path, a variable coupler comprising a first 2×2 combiner, a phase modulator and a second 2×2 combiner, a control detector configured to generate, from the complementary beam, an error signal (ε), a feedback loop configured to determine, from the error signal, the delay and the phase difference to be applied.
Device and system for coherently recombining multi-wavelength optical beams
An elementary device for coherently recombining a first elementary beam and a second elementary beam, includes a first input and a second input, into which are respectively injected the first elementary beam and the second elementary beam to be recombined, an output that delivers an output beam corresponding to the coherent recombination of the first and second elementary beams, a delay line placed on one of the paths of said elementary beams and configured to induce a variable delay on said path, a variable coupler comprising a first 2×2 combiner, a phase modulator and a second 2×2 combiner, a control detector configured to generate, from the complementary beam, an error signal (ε), a feedback loop configured to determine, from the error signal, the delay and the phase difference to be applied.