Systems and methods for optical modulation index calibration in a CATV network.

Embodiments relate to providing simultaneous digital and analog services in optical fiber-based distributed radio frequency (RF) antenna systems (DASs), and related components and methods. A multiplex switch unit associated with a head-end unit of a DAS can be configured to receive a plurality of analog and digital downlink signals from one or more sources, such as a service matrix unit, and to assign each downlink signal to be transmitted to one or more remote units of the DAS. In one example, when two or more downlink signals are assigned to be transmitted to the same remote unit, a wave division multiplexer/demultiplexer associated with the multiplex switch unit can be configured to wave division multiplex the component downlink signals into a combined downlink signal for remote side transmission and to demultiplex received combined uplink signals into their component uplink signals for head-end side transmission.

An active optical combiner for a CATV network.

According to an aspect of an embodiment, a method may include assigning an activation window by an optical line terminal during a portion of an upstream transmitting window in a passive optical network (PON). The method may include performing a first modification to a first upstream transmission. The method may include performing a second modification to a second upstream transmission. The method may include receiving the first upstream transmission from a first optical network unit (ONU) during the activation window, the first ONU synchronized in the PON. The method may include receiving a second upstream transmission from a second ONU during the activation window, the second ONU requesting activation in the PON.

Methods and systems for reducing power consumption in a multi-channel passive optical network (PON). A processor in the PON may monitor the channels in the multi-channel PON to detect a currently inactive channel, determine whether the detected channel has been inactive for an extended period of time, and deactivate the detected channel (by deenergizing transmitter(s) and/or receiver(s) associated with the detected channel) in response to determining that the channel has remained inactive for an extended period of time. The processor may re-activate the channel in response to determining that an optical signal has been reliably present on the channel for a sufficient period of time.

Embodiments of the present invention provide an optical network unit ONU registration method, apparatus, and system, to resolve a problem in the prior art that a registration process is cumbersome. The method includes: receiving an uplink optical signal, where the uplink optical signal carries ONU authentication information; sending the optical signal to a corresponding MAC module separately according to a wavelength of uplink light; extracting, by the MAC module, the ONU authentication information, and sending the extracted ONU authentication information to a processor; and receiving, by the processor, the ONU authentication information, and determining whether the ONU authentication information is consistent with ONU authentication information configured by an OLT, where if the ONU authentication information is consistent with the ONU authentication information configured by the OLT, an ONU is registered successfully.

A time-frequency multiple access system includes a central node and a first leaf node. The method provides a first leaf node sends a first uplink signal to the central node. The first leaf node receives first information and second information from the central node. The first information and the second information are determined based on the first uplink signal. The first information indicates a transmit wavelength of a laser of the first leaf node, and the second information indicates a first uplink sending window. The first leaf node sends, in the first uplink sending window, a second uplink signal to the central node via the laser at a first wavelength. The first wavelength is determined based on the first information, and the first uplink sending window is determined based on the second information.