An apparatus grouping data units for optical network units into groups of Encapsulation Method, EM, frame(s), wherein a respective group of EM frame(s) include data units addressed to a respective subset of ONUs, generating, based on the groups of EM frame(s), a Framing Sublayer payload including at least one specific frame, wherein, the specific frame includes a length indicator determined in relation to the length of the group(s) of EM frame(s) that is(are) directly following the specific frame and is(are) addressed to at least one subset of ONUs; instructing the ONUs assigned to at least one of said at least one subset to process the EM frame directly following the specific frame, and instructing the ONUs not assigned to the at least one subset to process the EM frame that is indicated by the length indicator of the specific frame; and transmitting the Framing Sublayer payload to the ONUs.

Processing a received optical signal in an optical communication network includes equalizing a received optical signal to provide an equalized signal, demodulating the equalized signal according to an m-ary modulation format to provide a demodulated signal, decoding the demodulated signal according to an inner code to provide an inner-decoded signal, and decoding the inner-decoded signal according to an outer code. Other aspects include other features such as equalizing an optical channel including storing channel characteristics for the optical channel associated with a client, loading the stored channel characteristics during a waiting period between bursts on the channel, and equalizing a received burst from the client using the loaded channel characteristics.

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 wavelength division multiplexing filter comprises: a first multi-order Mach-Zehnder interferometer comprising a plurality of first-order Mach-Zehnder interferometers, and a second multi-order Mach-Zehnder interferometer comprising a plurality of first-order Mach-Zehnder interferometers; wherein the first multi-order Mach-Zehnder interferometer and the second multi-order Mach-Zehnder interferometer are included in a group of multiple multi-order Mach-Zehnder interferometers arranged within a binary tree arrangement, the binary tree arrangement comprising: a first set of a plurality of multi-order Mach-Zehnder interferometers, the first set including the first multi-order Mach-Zehnder interferometer, and having an associated spectral response with a first spacing between adjacent passbands, and a second set of at least twice as many multi-order Mach-Zehnder interferometers as in the first set, the second set including the second multi-order Mach-Zehnder interferometer, and having an associated spectral response with a second spacing between adjacent passbands that is twice the first spacing.

A communications network includes a central communication unit, an optical transport medium, and a plurality of remote radio base stations. The central communication unit generates, within a selected millimeter-wave frequency band, a plurality of adjacent two-tone optical frequency conjugate pairs. Each conjugate pair includes a first optical tone carrying a modulated data signal, and a second optical tone carrying a reference local oscillator signal. The optical transport medium transports the plurality of two-tone conjugate pairs to the plurality of radio base stations, and each base station receives at least one conjugate pair at an optical front end thereof. The optical front end separates the first optical tone from the second optical tone, and converts the first optical tone into a millimeter-wave radio frequency electrical signal. The base station further includes a radio antenna system for wirelessly transmitting the millimeter-wave radio frequency electrical signal to at least one wireless receiving device.

An intelligence-defined optical tunnel network system includes pods. Each pod includes optical add-drop sub-systems. Each optical add-drop sub-system includes a first transmission module and a second transmission module. The first transmission modules of the optical add-drop sub-systems are connected to each other for forming a first transmission ring. The second transmission modules of the optical add-drop sub-systems are connected to each other for forming a second transmission ring. Each first transmission module includes a multiplexer and an optical signal amplifier. The multiplexer is connected to a Top-of-Rack switch. The multiplexer is configured to receive, through input ports, upstream optical signals from the Top-of-Rack switch, and combine the upstream optical signals into a composite optical signal. The upstream optical signals have wavelengths respectively. The optical signal amplifier, coupled to the multiplexer, is configured to amplify the composite optical signal and output an amplified composite optical signal.

Systems, apparatuses, methods, and computer program products are disclosed for managing premise-level data communication in a wavelength division multiplexing (WDM) fiber optic network. An example method includes receiving, by a control system, a message from a new device connected to the WDM fiber optic network, the message including one or more service provider identifiers, a customer identifier, and a customer equipment identifier of the new device. The method further includes transmitting, by the control system, a configuration command to the new device, the configuration command including (i) an indication of which wavelengths the new device may utilize, and (ii) an indication of message types that may be transmitted using each wavelength the new device may utilize. The method further includes causing, by the control system, transmission of a service fee to each service provider associated with a service provider identifier of the one or more service provider identifiers.

A coherent passive optical network includes a downstream transceiver and first and second upstream transceivers in communication with an optical transport medium. The downstream transceiver includes a downstream processor for mapping a downstream data stream to a plurality of sub-bands, and a downstream transmitter for transmitting a downstream optical signal modulated with the plurality of sub-bands. The first upstream transceiver includes a first local oscillator (LO) for tuning a first LO center frequency to a first sub-band of the plurality of sub-bands, and a first downstream receiver for coherently detecting the downstream optical signal within the first sub-band. The second upstream transceiver includes a second downstream receiver configured for coherently detecting the downstream optical signal within a second sub-band of the plurality of sub-bands. The downstream processor dynamically allocates the first and second sub-bands to the first and second transceivers in the time and frequency domains.

An injection locked transmitter for an optical communication network includes a master seed laser source input substantially confined to a single longitudinal mode, an input data stream, and a laser injected modulator including at least one slave laser having a resonator frequency that is injection locked to a frequency of the single longitudinal mode of the master seed laser source. The laser injected modulator is configured to receive the master seed laser source input and the input data stream, and output a laser modulated data stream.

An ROF communication remote machine and an ROF system are disclosed. The machine comprises a first packaging module and a second packaging module. The first packaging module comprises a first branch and a second branch The first branch is used for converting a downlink optical signal, and sending the downlink electrical signal to the second packaging module. The second branch receives the downlink electrical signal, converts the downlink electrical signal into a downlink optical signal, sends the downlink optical signal to the local machine, receives an uplink electrical signal, and sends the uplink electrical signal to the local machine. The second packaging module is used for amplifying the power of the downlink electrical signal, filtering the downlink electrical signal, then feeding back the downlink electrical signal to another component, receiving the uplink electrical signal, and sending the uplink electrical signal to the second port.