Optical signal receivers and methods are provided that include multiple optical resonators, each of which receives a portion of an arriving optical signal. Various of the optical resonators are tuned or detuned from a carrier wavelength, and produce an intensity modulated output signal in response to modulation transitions in the arriving optical signal. A detector determines phase transitions in the arriving optical signal, by analyzing the intensity modulation output signals from the optical resonators, and distinguishes between differing phase transitions that result in a common final state of the arriving optical signal.

Optical receivers and methods for balanced signal detection using an optical resonator. An example of an optical receiver includes a polarizing beamsplitter that receives a free-space optical signal, a first detector positioned to receive the free-space optical signal with the first polarization, an alignment system configured to rotate either the optical receiver about the optical axis or a polarization of the free-space optical signal, a faraday rotator configured to rotate the polarization of the free-space optical signal, an optical resonator that receives the free-space optical signal from the faraday rotator and accumulates resonant optical signal energy, the optical resonator configured to transmit first output optical signal energy and reject second output optical signal energy, the optical resonator being configured to convert a modulation of the free-space optical signal into an intensity modulation of the first and second output optical signal energies, a second detector that receives the first output optical signal energy and detects the intensity modulation of the first output optical signal energy, and a third detector that receives the second output optical signal energy.

Optical receivers configured to demodulate phase modulated optical signals. In one example, an optical signal receiver includes an optical resonator configured to receive an arriving optical signal and to emit an output optical signal in response to receiving the arriving optical signal, the optical resonator being further configured to transform phase transitions corresponding to phase modulation of the arriving optical into intensity modulation of the output optical signal, an opto-electrical converter configured to convert the output optical signal into an electrical signal, a pulse detector configured to detect pulses in the electrical energy indicative of the phase transitions in the arriving optical signal, and a memory configured to record timing information associated with the pulses detected by the pulse detector.

The present invention is directed to a communication signal tracking system comprising an optical receiver including one or more delay line interferometers (DLIs) configured to demultiplex incoming optical signals and a transimpedance amplifier configured to convert the incoming optical signals to incoming electrical signals. The communication signal tracking system further includes a control module configured to calculate a bit-error-rate (BER) of the incoming electrical signals before forward-error correction decoding, and use the BER as a parameter for optimizing settings of the one or more DLIs in one or more iterations in a control loop and generating a back-channel data.

Optical signal receivers and methods are provided that include an optical resonator that allows optical signal energy of multiple wavelengths to enter and accumulate inside the optical resonator. A portion of optical signal energy of each wavelength is emitted from the optical resonator at an output, and the individual wavelengths may be separated. A detector aligned with the output detects the emitted optical signal energy of at least one of the wavelengths. The detector is configured to detect disturbances to the emitted optical signal energy and determine a modulated characteristic in the received optical signal energy of the wavelength.

An apparatus for generating a processed optical signal includes a first laser configured to emit a first optical signal in response to a first drive signal. The first optical signal has a first phase shift depending on a first integrated amplitude of the first drive signal. The apparatus also includes a spectral-temporal filter, in optical communication with the first laser, to change a first spectral profile and a first temporal profile of the first optical pulse so as to generate the processed optical signal. Replacing a conventional continuous-wave (CW) laser and external modulation with filter-based modulation can achieve the same or better performance without high-fidelity low-noise input signals.

The present invention is directed to a communication signal tracking system comprising an optical receiver including one or more delay line interferometers (DLIs) configured to demultiplex incoming optical signals and a transimpedance amplifier configured to convert the incoming optical signals to incoming electrical signals. The communication signal tracking system further includes a control module configured to calculate a bit-error-rate (BER) of the incoming electrical signals before forward-error correction decoding, and use the BER as a parameter for optimizing settings of the one or more DLIs in one or more iterations in a control loop and generating a back-channel data.

The present disclosure relates to a method for transmitting or receiving a signal by a reception device in a wireless communication system, and the method may comprise the steps of: receiving, from a transmission device, a signal modulated on the basis of a differential phase shift keying (DPSK) scheme; converting the received signal into an input signal of a spiking neural network (SNN); calculating an output value through the spiking neural network previously learned; and converting the output value into an input signal of a channel decoder.

Optical signal receivers and methods are provided that include an optical resonator that allows optical signal energy of multiple wavelengths to enter and accumulate inside the optical resonator. A portion of optical signal energy of each wavelength is emitted from the optical resonator at an output, and the individual wavelengths may be separated. A detector aligned with the output detects the emitted optical signal energy of at least one of the wavelengths. The detector is configured to detect disturbances to the emitted optical signal energy and determine a modulated characteristic in the received optical signal energy of the wavelength.

A method includes: sending, by a signal transmitting device, a first PAM signal to a signal receiving device, where the first PAM signal includes N first level amplitudes, and N3; receiving, by the transmitting device, feedback parameters sent by the receiving device, where the feedback parameters are determined based on the first PAM signal; determining, by the transmitting device, N target level amplitudes based on the feedback parameters, where intervals between every two adjacent target level amplitudes in the N target level amplitudes are different from each other; and generating, by the transmitting device based on the N target level amplitudes, a second PAM signal that needs to be sent to the receiving device.