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.

Embodiments of this application disclose an optical switch. The optical switch includes at least one first port, at least one second port, a first wavelength division multiplexing WDM apparatus, an optical splitter, an optical monitoring apparatus, and an optical switching apparatus. The first port is configured to transmit an input first optical signal to the first WDM apparatus, where the first optical signal is a multi-wavelength signal. The first WDM apparatus is configured to demultiplex the first optical signal. The optical splitter is configured to split a demultiplexed first optical signal to obtain a first sub-signal and a second sub-signal. The optical switching apparatus is configured to perform optical switching on the first sub-signal. The second port is configured to output a first sub-signal obtained after optical switching. The optical monitoring apparatus is configured to perform optical performance monitoring on the second sub-signal.

One embodiment described herein provides a co-packaged optics (CPO) switch assembly. The CPO switch assembly includes a switch integrated circuit (IC) chip and a number of optical modules coupled to the switch IC chip. The switch IC chip and the optical modules are co-packaged within a same physical enclosure. The switch IC chip includes a switch logic and a digital signal processing (DSP) unit, and a respective optical module comprises: a photonic integrated chip (PIC), a first amplifier module, and a second amplifier module.

One embodiment described herein provides a co-packaged optics (CPO) switch assembly. The CPO switch assembly includes a switch integrated circuit (IC) chip and a number of optical modules coupled to the switch IC chip. The switch IC chip and the optical modules are co-packaged within a same physical enclosure. The switch IC chip includes a switch logic and a digital signal processing (DSP) unit, and a respective optical module comprises: a photonic integrated chip (PIC), a first amplifier module, and a second amplifier module.

Various embodiments of the disclosed PON system enable approximate leveling of the optical-modulation amplitudes in a sequence of optical bursts received by a system's OLT from a plurality of ONUs. Some embodiments additionally enable approximate leveling of the average optical power, received at the OLT from different ONUs, in such a sequence. Some embodiments may rely on control messaging between the OLT and ONUs to perform one or both types of leveling. The disclosed leveling may advantageously provide an effective tool for optimizing upstream transmission for high-speed TDM-PONs.

A system installed in a cross-border area between a provider network of a provider and a customer network of a customer includes: a smart optical network termination device (NT) at a site of the customer, wherein the smart optical NT is configured to implement a demarcation point between the customer network and the provider network, and wherein the smart optical NT is independent of a data rate passing through it and an optical interface connected to it; and a monitoring device located at a point of presence (PoP) of the provider network. The smart optical NT is further configured to monitor a coupling of optical power by the customer into the provider network and to interact with the monitoring device via at least one traffic analysis point (TAP) for connectivity validation from the PoP to the demarcation point.

Described are various configurations of reduced crosstalk optical switches. Various embodiments can reduce or entirely eliminate crosstalk using a coupler that has a power-splitting ratio that compensates for amplitude imbalance caused by phase modulator attenuation. Some embodiments implement a plurality of phase modulators and couplers as part of a dilated switch network to increase overall bandwidth and further reduce potential for crosstalk.

A method for noise suppression in a colorless optical add/drop system implemented prior to a colorless optical add/drop device includes, subsequent to receiving an optical signal from an optical modem, filtering the optical signal with a wavelength blocking filter to suppress out of band Amplified Stimulated Emission (ASE) in order to prevent noise funneling in the colorless optical add/drop device; and providing the filtered optical signal with the out of band ASE suppressed therein to a multiplexer port in the colorless optical add/drop device. The method can include, prior to the filtering, amplifying the optical signal with a single channel amplifier, wherein the single channel amplifier can include a pump laser shared with one or more additional single channel amplifiers.

An optical switch with a plurality of actuators includes a controller configured to control the operation of a plurality of channels, where each channel has at least one electrical driver and at least one actuator, by interleaving periods of voltage switching output with periods of no voltage switching output for one or more drivers whilst the output voltage is switching from one level to another level. Alternatively, an optical switch with a plurality of actuators comprises a controller configured to control the operation of a plurality of channels, where each channel has at least one electrical driver and at least one actuator, by switching the output voltage from one level to another level for at least one driver of a first channel whilst at least one oilier driver of at least one other channel is in a relatively high impedance mode.

The present disclosure discloses a data transmission method, an apparatus, and a system. The method includes: receiving, by a mode multiplexer from an input port, a first optical signal transmitted by an optical line terminal; converting, according to a correspondence between an input port of an optical signal and a mode of the optical signal, the received first optical signal into a second optical signal in a mode corresponding to the input port; and multiplexing the second optical signal obtained by means of conversion to a few-mode optical fiber for transmission. This increases transmission capacity of a single optical fiber and implements fast expansion of the transmission capacity, thereby improving total bandwidth utilization of a system.