Techniques are described for providing a hybrid compensation of chromatic dispersion in optical networks to reduce power consumption by coherent receivers. In some examples, a controller may receive a chromatic dispersion value of an optical signal from a coherent receiver integrated with a receiver optical network device. The controller may compare the chromatic dispersion value with a threshold. The controller may, in response to determining that the chromatic dispersion value satisfies the threshold, perform at least one of: configure a switch connected to a dispersion compensation module (DCM) with a state to provide access to the DCM to compensate the chromatic dispersion value of the optical signal, or adjust a phase response of a filter of a coherent transmitter to compensate the chromatic dispersion value of the optical signal.

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.

A module handles beams having multiple channels in an optical network. The module has a dispersion element, a liquid crystal (LC) based switching assembly, and photodetectors. The dispersion element is arranged in optical communication with the beams from inputs and is configured to disperse the beams into the channels across a dispersion direction. The switching assembly is arranged in optical communication with the channels from the dispersion element and is configured to selectively reflect the channels using electrically switchable cells of one or more LC-based switching engines. The photodetectors are arranged in optical communication with the dispersion element, and each are configured to receive selectively reflected channels for optical channel monitoring. Outputs can be arranged in optical communication with the dispersion element and can be configured to receive selectively reflected channels for wavelength selective switching.

A module handles beams having multiple channels in an optical network. The module has a dispersion element, a liquid crystal (LC) based switching assembly, and photodetectors. The dispersion element is arranged in optical communication with the beams from inputs and is configured to disperse the beams into the channels across a dispersion direction. The switching assembly is arranged in optical communication with the channels from the dispersion element and is configured to selectively reflect the channels using electrically switchable cells of one or more LC-based switching engines. The photodetectors are arranged in optical communication with the dispersion element, and each are configured to receive selectively reflected channels for optical channel monitoring. Outputs can be arranged in optical communication with the dispersion element and can be configured to receive selectively reflected channels for wavelength selective switching.

A system and method for extending the path length of an electromagnetic wave signal traveling between apertures is disclosed. One such system may comprise N arrays having M.sub.1 through M.sub.N apertures, respectively, wherein N≥2, M.sub.1≥2, and each of M.sub.2 through M.sub.N≥1, a substantial number of the M.sub.1 apertures in a first array is configured to send the electromagnetic wave signal to a substantial number of the M.sub.2 apertures in a second array through the M.sub.N apertures in a N-th array, the substantial number of the M.sub.2 apertures in the second array through the M.sub.N apertures in the N-th array receiving the electromagnetic wave signal from the substantial number of the M.sub.1 apertures in the first array is configured to redirect the received electromagnetic wave signal back to the substantial number of the M.sub.1 apertures in the first array, and the substantial number of the M.sub.1 apertures in the first array is further configured to send the electromagnetic wave signal to another one of the M.sub.1 apertures in the first array after receiving the redirected electromagnetic wave signal from a M.sub.N-th aperture in the N-th array.

A system and method for extending the path length of an electromagnetic wave signal traveling between apertures is disclosed. One such system may comprise N arrays having M.sub.1 through M.sub.N apertures, respectively, wherein N≥2, M.sub.1≥2, and each of M.sub.2 through M.sub.N≥1, a substantial number of the M.sub.1 apertures in a first array is configured to send the electromagnetic wave signal to a substantial number of the M.sub.2 apertures in a second array through the M.sub.N apertures in a N-th array, the substantial number of the M.sub.2 apertures in the second array through the M.sub.N apertures in the N-th array receiving the electromagnetic wave signal from the substantial number of the M.sub.1 apertures in the first array is configured to redirect the received electromagnetic wave signal back to the substantial number of the M.sub.1 apertures in the first array, and the substantial number of the M.sub.1 apertures in the first array is further configured to send the electromagnetic wave signal to another one of the M.sub.1 apertures in the first array after receiving the redirected electromagnetic wave signal from a M.sub.N-th aperture in the N-th array.

In one embodiment, an intensity modulated (IM) direct detection (DD) optical receiver using a photonic integrated circuit (PIC) with an array of semiconductor optical amplifiers (SOAs) for flexible chromatic dispersion compensation (CDC) is provided. The PIC comprises an 1:N optical splitter to split an input optical signal into N copies; an array of N semiconductor optical amplifiers (SOAs) to receive the N optical outputs from the optical splitter; an array of optical delay lines to receive the outputs from the N SOAs, wherein the delay coefficients for the array of optical delay lines are {0, T, 2T, . . . (N-1) T}, where T =1/2B, where B is the system symbol rate, and each optical path with odd index (1, 3, 5, . . .N-1) from the N optical paths includes a 90-degree phase-shifter; and an optical N:1 coupler to re- combine all N optical paths. A method for automatically controlling a PIC based on the feedback signal from the Rx DSP in an optical receiver is also provided.

In one embodiment, an intensity modulated (IM) direct detection (DD) optical receiver using a photonic integrated circuit (PIC) with an array of semiconductor optical amplifiers (SOAs) for flexible chromatic dispersion compensation (CDC) is provided. The PIC comprises an 1:N optical splitter to split an input optical signal into N copies; an array of N semiconductor optical amplifiers (SOAs) to receive the N optical outputs from the optical splitter; an array of optical delay lines to receive the outputs from the N SOAs, wherein the delay coefficients for the array of optical delay lines are {0, T, 2T, . . . (N-1) T}, where T =1/2B, where B is the system symbol rate, and each optical path with odd index (1, 3, 5, . . .N-1) from the N optical paths includes a 90-degree phase-shifter; and an optical N:1 coupler to re- combine all N optical paths. A method for automatically controlling a PIC based on the feedback signal from the Rx DSP in an optical receiver is also provided.

In response to the above issue, an object of the present invention is to provide a diagnostic apparatus and a diagnostic method capable of accurately recognizing whether to use a long extension function at the time of relocation of an accommodation station of an OLT. The diagnostic apparatus according to an aspect of the present invention has an allowable line length list that is a relationship between a center wavelength and an allowable line distance that satisfies a selected spectrum width in an optical fiber used in an optical communication system, measures a center wavelength and a spectrum width of a spectrum for each ONU, matches the allowable line length list, and obtains an allowable line distance of each ONU.

An optical transmission and reception system includes an optical transmitter that converts an electrical data signal into an optical signal and transmits the optical signal; and an optical receiver that receives the optical signal input from the optical transmitter via an optical transmission line and converts the optical signal into the data signal. The optical transmitter includes a first compensator that compensates for a loss generated in the optical transmitter based on a first coefficient and a second coefficient, and the optical receiver includes a second compensator that compensates for a loss generated in the optical transmission line based on a third coefficient.