An optical module is disclosed. The optical module includes a first downlink port, a second downlink port, a directional coupler, a optical attenuator, a first photodiode (PD), and a second PD. The directional coupler, connected to the first downlink port, is configured to receive a downlink optical signal. The second PD connected to the directional coupler, is configured to obtain a power value. If the power value is greater than a first threshold, the optical attenuator is configured to receive a attenuation control signal, and attenuate, based on the attenuation control signal, a power of an optical signal passing through the second downlink port. The first PD is configured to: convert the downlink optical signal into a downlink electrical signal, and convert the optical signal passing through the second downlink port into an electrical signal. Both the first downlink port and the second downlink port are connected to the first PD.

A method is provided for assessing the quality of an optical transmitter and/or its interoperability with a receiver. The method includes obtaining an optical signal output by an optical transmitter and performing coherent optical-to-electrical detection of the optical signal to produce an in-phase receive signal and a quadrature receive signal. The method further includes a computing device emulating a worst-case configuration of an optical fiber with which the optical transmitter is to be used, based on the in-phase receive signal and the quadrature receive signal to produce a noise contribution associated with the worst-case characteristics of the optical fiber and determining a figure of merit of the optical transmitter based on the noise contribution.

Provided are a signal processing method and apparatus, a storage medium, and an electronic apparatus. The method is applied to an optical communication receiving end, and comprises: after receiving an optical analog signal, converting the optical analog signal into a digital signal; and performing nonlinear effect compensation processing on the digital signal.

Proposed are an optimal operation method of a high-frequency dithering technique for compensating for interference noise in an analog optical transmission-based mobile fronthaul network, and a transmitter using same. An interference noise compensation method using high-frequency phase dithering performed in an analog optical transmission-based mobile fronthaul network may include the steps in which: a frequency-multiplexed wireless signal is converted in an optical transmitter to an intensity-modulated optical signal; and the phase of the optical signal intensity-modulated in the optical transmitter is dithered with an Orthogonal Frequency-Division Multiplexing (OFDM) signal.

Proposed are an optimal operation method of a high-frequency dithering technique for compensating for interference noise in an analog optical transmission-based mobile fronthaul network, and a transmitter using same. An interference noise compensation method using high-frequency phase dithering performed in an analog optical transmission-based mobile fronthaul network may include the steps in which: a frequency-multiplexed wireless signal is converted in an optical transmitter to an intensity-modulated optical signal; and the phase of the optical signal intensity-modulated in the optical transmitter is dithered with an Orthogonal Frequency-Division Multiplexing (OFDM) signal.

An optical communication system includes a first optical communication device; a plurality of second optical communication devices configured to perform communication with the first optical communication device; a chromatic dispersion compensation device connected to the first optical communication device; and an optical transmission line connected to the chromatic dispersion compensation device, a path of the optical transmission line connected to the chromatic dispersion compensation device being split into a plurality of paths at a branch point, the resulting paths being respectively connected to the plurality of second optical communication devices, and the optical transmission line being configured to transmit optical signals through the paths, in which the chromatic dispersion compensation device includes a chromatic dispersion compensator configured to perform chromatic dispersion compensation corresponding to amounts of chromatic dispersion generated in optical signals propagated through respective paths between the first optical communication device and the plurality of second optical communication devices.

An optical communication system includes a first optical communication device; a plurality of second optical communication devices configured to perform communication with the first optical communication device; a chromatic dispersion compensation device connected to the first optical communication device; and an optical transmission line connected to the chromatic dispersion compensation device, a path of the optical transmission line connected to the chromatic dispersion compensation device being split into a plurality of paths at a branch point, the resulting paths being respectively connected to the plurality of second optical communication devices, and the optical transmission line being configured to transmit optical signals through the paths, in which the chromatic dispersion compensation device includes a chromatic dispersion compensator configured to perform chromatic dispersion compensation corresponding to amounts of chromatic dispersion generated in optical signals propagated through respective paths between the first optical communication device and the plurality of second optical communication devices.

A method for chromatic dispersion pre-compensation in an optical communication network includes (1) distorting an original modulated signal according to an inverse of a transmission function of the optical communication network, to generate a compensated signal, (2) modulating a magnitude of an optical signal in response to a magnitude of the compensated signal, and (3) modulating a phase of the optical signal, after modulating the magnitude of the optical signal, in response to a phase of the compensated signal.

An optical reception device includes a coefficient update section which optimizes a dispersion coefficient used in compensation of wavelength dispersion of a received signal obtained by receiving an optical signal according to a coherent detection method and a phase rotation amount used in compensation of a nonlinear optical effect of the received signal, and a transmission characteristic estimation section which estimates a transmission characteristic of a transmission line by using the optimized dispersion coefficient and the optimized phase rotation amount.

A first optical transceiver includes a transmission signal processor that generates a multi-valued pulse amplitude modulation signal including a fixed bit pattern. The first optical transceiver includes an optical transmitter that transmits the multi-valued pulse amplitude modulation signal as an optical transmission signal. The first optical transceiver includes an optical receiver that receives an optical adjustment signal from a second optical transceiver to reproduce an adjustment signal from the optical adjustment signal. The first optical transceiver includes a first controller that controls the transmission signal processor based on a bit error rate included in the optical adjustment signal to adjust light power at each level of the optical transmission signal.