An optical transmitter can generate probabilistically shaped quadrature amplitude modulation (PS-QAM) signaling for transmission over a fiber to a destination without optical amplification. The single fiber can transmit the PS-QAM signaling using dense wavelength division multiplexing having a relatively large number of channels that are closely spaced. A coherent receiver can receive the PS-QAM signaling for decoding without implementing chromatic dispersion compensation.

A system for routing signals in a Distributed Antenna System (DAS) includes one or more local Digital Access Units (DAUs) located at a local location and one or more remote DAUs located at one or more remote locations. Each of the one or more local DAUs includes an optical port coupled to an upstream unit. The upstream unit includes at least one of a repeater, a baseband unit, a Base Transceiver Station (BTS), or a DAU. The one or more remote DAUs are coupled to the one or more local DAUs via one or more optical cables. A distance between the local location and each of the one or more remote locations is greater than two kilometers.

This disclosure describes devices and methods related to multiplexing optical data signals. A method may be disclosed for multiplexing one or more optical data signals. The method may comprise receiving, by a dense wave division multiplexer (DWDM), one or more optical data signals. The method may comprise combining, by the DWDM, the one or more optical data signals. The method may comprise outputting, by the DWDM, the combined one or more optical data signals to one or more wave division multiplexer (WDM). The method may comprise combining, by the one or more WDM, the combined one or more optical data signals and one or more second optical data signals, and outputting an egress optical data signal comprising the combined one or more optical data signals and one or more second optical data signals.

An optical network communication system includes an optical hub, an optical distribution center, at least one fiber segment, and at least two end users. The optical hub includes an intelligent configuration unit configured to monitor and multiplex at least two different optical signals into a single multiplexed heterogeneous signal. The optical distribution center is configured to individually separate the at least two different optical signals from the multiplexed heterogeneous signal. The at least one fiber segment connects the optical hub and the optical distribution center, and is configured to receive the multiplexed heterogeneous signal from the optical hub and distribute the multiplexed heterogeneous signal to the optical distribution center. The at least two end users each include a downstream receiver configured to receive one of the respective separated optical signals from the optical distribution center.

An optical network communication system includes an optical hub, an optical distribution center, at least one fiber segment, and at least two end users. The optical hub includes an intelligent configuration unit configured to monitor and multiplex at least two different optical signals into a single multiplexed heterogeneous signal. The optical distribution center is configured to individually separate the at least two different optical signals from the multiplexed heterogeneous signal. The at least one fiber segment connects the optical hub and the optical distribution center, and is configured to receive the multiplexed heterogeneous signal from the optical hub and distribute the multiplexed heterogeneous signal to the optical distribution center. The at least two end users each include a downstream receiver configured to receive one of the respective separated optical signals from the optical distribution center.

In general, techniques are described for dynamically determining a logical network topology for more efficiently transporting network traffic over a physical topology based on end-to-end network traffic demands and optical transport network (OTN) characteristics of the network. The techniques may be applicable to meeting network traffic demands placed upon a multi-layer network having a base transport layer and a logical or overlay Internet Protocol (IP) layer routed on the transport layer.

An optical communication system with a hierarchical branch configuration. The system includes first and second cable landing stations coupled to a trunk path in an optical cable. At least one hub-node is coupled to the trunk path through an associated hub-node branching unit. Sub-nodes are coupled the hub-nodes through associated sub-node branching units and sub-node paths in the optical cable. Sub-node signals may be communicated between the sub-nodes and the hub-nodes without being provided on the trunk path.

A system, a non-transitory computer readable media and a method for intra data center optical communication, the method may include (a) receiving an optical input signal by a coherent optical receiver of a second unit of a data center; wherein each input optical signal represents a transmitted optical signal that was transmitted by a coherent transmitter of a first unit of the data center; wherein the transmitted optical signal is generated by modulating a transmitter laser signal that is outputted from a laser of the coherent transmitter; (b) generating, by a controllable laser of the coherent optical receiver, a reference signal; wherein a frequency of the reference signal is controlled by a processor of the coherent optical receiver; and (c) recovering data embedded in the optical input signal; wherein the recovering of the data comprises optically processing the reference signal and the optical input signal.

An optical network includes top networking ports coupled to a packet switch, first media converters, second media converters, and bottom networking ports. The first media converters are coupled to top networking ports, each of the first media converters including a first ASIC transceiver that has a circuit switch function. The second media converters are coupled to the first media converter via optical cables to receive the optical signals. Each of the second media converters includes a second ASIC transceiver that has a circuit switch function. The bottom networking ports are coupled to the second media converters. The first ASIC transceiver and the second ASIC transceiver are configured to transmit a signal from one of the top networking ports to any one of the bottom networking ports, and transmit a signal from one of the bottom networking ports to any one of the top networking ports.

A system for routing signals in a Distributed Antenna System (DAS) includes one or more local Digital Access Units (DAUs) located at a local location and one or more remote DAUs located at one or more remote locations. Each of the one or more local DAUs includes an optical port coupled to an upstream unit. The upstream unit includes at least one of a repeater, a baseband unit, a Base Transceiver Station (BTS), or a DAU. The one or more remote DAUs are coupled to the one or more local DAUs via one or more optical cables. A distance between the local location and each of the one or more remote locations is greater than two kilometers.