A test device tests conditions associated with a fronthaul in an Open Radio Access Network (O-RAN). The test device can field test an O-RAN radio unit (O-RU) installed at a cell site by emulating an O-RAN distributed unit (O-DU) in the O-RAN connected to the O-RU via the fronthaul of the O-RAN. The testing includes testing connectivity of the O-RU to the fronthaul. The testing includes executing managing plane (M-plane) and synchronization plane (S-plane) messaging to test management session establishment, device setting testing, and master clock synchronization testing. Additionally, optical insertion loss in the fronthaul and frequency and power of signals transmitted from the O-RU can be tested.

A photonic synthesizer includes a multifrequency optical source to produce a signal of interest from a pair of lasers, which may be self-injection locked chip lasers. The signal is referenced to a high frequency clock using a photonic mixer/divider based on an electro-optical modulator and a relatively slow photodiode. The electro-optical modulator produces optical harmonics from the beams from the pair of lasers, where one harmonic from the first laser beam and one harmonic from the second laser beam beat on the photodiode. A phase locked control signal is generated for controlling the output frequency of one or both of the two lasers. The output signal of the photonic synthesizer is generated using a relatively fast photodiode based on a difference in frequencies of the pair of lasers. The output signal may be a millimeter wave-band signal. The photonic synthesizer can be formed as a photonic integrated circuit (PIC).

An optical communication device includes a WDM optical transmission reception unit that receives an optical signal and converts the optical signal to an electric signal, a MUX/DEMUX unit that converts the electric signal obtained by the conversion to a plurality of electric signals, signal detection units, a switch unit that changes paths, client IF units, and a control unit. A first signal detection unit among the signal detection units detects a first electric signal among the plurality of electric signals. When the first electric signal is a signal to be processed based on a first communication standard, the control unit controls the switch unit so that the first electric signal is inputted to a client IF unit that executes a process based on the first communication standard among the client IF units.

A radio-frequency data transport infrastructure for transmitting radio-frequency data to and from equipment via optical fibers. Such data transport infrastructure being particularly suitable for equipping an aircraft

An interference canceling subsystem for a bidirectional communications network includes an input interface configured to receive a first data signal from a first transceiver of the network, an output portion configured to receive a second data signal from a second transceiver of the network, a first signal path connecting the input interface to the output portion, a second signal path connecting the output portion to the input interface, and a first interference canceler disposed between the output portion and the input interface along the second signal path. The first signal path is configured to relay the first data signal from the input interface to the output portion. The interference canceler is configured to (i) relay the second data signal from the output portion to the input interface, and (ii) remove portions of the first data signal from the relayed second data signal prior to reaching the input interface.

Software Defined Networking concepts apply to access, fronthaul, backhaul and core networks of 5G mobile networks and beyond. Such network components currently have individual/segmented control planes and associated controllers to provide configurability, provisioning, and network slicing. This is because of technology disparity between these network components: access is wireless/cellular, backhaul and fronthaul are optical/fiber, and core is electrical/wire-line. A system/method is detailed that enables a coordinated and unified end-to-end slicing, wherein the coordination is provided in the system/method that (a) attaches to the respective controllers of these network components in real-time, (b) collects the connectivity topology of each network segment as the network evolves, (c) passes the slice-profile information (translating according to capabilities of that network segment to configure an end-to-end slice with a specified bandwidth requirement and service quality level), and (d) passes across a VLAN tag to be used across network segments to associate with the same slice.

Methods, systems, and apparatus for communicating over a radio link by devices with broadband connectivity are disclosed. In one aspect, a telecommunications device includes a first transceiver, a second transceiver, and a state monitor. The first transceiver communicates over a broadband link. The second transceiver communicates over a radio link. The radio link is a Low-Power Wide-Area Network (LPWAN) link. The state monitor includes one or more processes that monitor a state of the telecommunications device, and in response to the state of the telecommunications device being one of a plurality of pre-specified states, transmit, using the second transceiver, data specifying the state of the telecommunications device over the radio link.

A terminal (1050) includes a light receiver (151) that receives a light signal emitted by an apparatus (1000), the light signal including an identifier (SSID) of at least one base station (470); a receiver (153) that performs a reception process on the received light signal to output reception data; a data analyzer (155) that selects one base station based on the identifier of the at least one base station that is included in the reception data; and a radio device (453) that establishes a wireless connection with the selected base station (470) by using the identifier of the base station (470) and wirelessly communicates with the base station (470).

A transmitter can include a laser operable to output an optical signal; a digital signal processor operable to receive user data and provide electrical signals based on the data; and a modulator operable to modulate the optical signal to provide optical subcarriers based on the electrical signals. A first one of the subcarriers carriers carries first TDMA encoded information and second TDMA encoded information, such that the first TDMA encoded information is indicative of a first portion of the data and is carried by the first one of the subcarriers during a first time slot, and the second TDMA encoded information is indicative of a second portion of the data and is carried by the first one of the subcarriers during a second time slot. The first TDMA encoded information is associated with a first node remote from the transmitter and the second TDMA encoded information is associated with a second node remote from the transmitter. A second one of the subcarriers carries third information that is not TDMA encoded, the third information being associated with a third node remote from the transmitter. A receiver and system also are described.

A radio over fiber (RoF) system and a nonlinear compensation method, where the RoF system includes a BBU and an RRU, the RRU includes an electrical component, and the BBU includes a downlink and a feedback link. A predistortion module and an optical component are disposed on the downlink, an input end of the feedback link is connected to an output end of the optical component, and the feedback link is configured to feed back, to the predistortion module, a nonlinear signal output by the optical component. The RoF system further includes a temperature detection module configured to detect a temperature value of the electrical component, and transmit the temperature value to the predistortion module. The predistortion module is configured to perform digital predistortion DPD on a baseband signal based on the temperature value and the nonlinear signal.