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 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 single-fiber bidirectional optical transmission apparatus, a wavelength division multiplexing device, and an optical transmission system, is disclosed. The single-fiber bidirectional optical transmission apparatus includes: a first single-light-source coherent optical transceiver, configured to: receive a first optical signal from a first multiplexer/demultiplexer, convert the first optical signal into a first electrical signal, and send the first electrical signal to a first client signal processing apparatus; and a second single-light-source coherent optical transceiver, configured to: receive a second electrical signal from the first client signal processing apparatus, convert the second electrical signal into a second optical signal, and send the second optical signal to the first multiplexer/demultiplexer. A wavelength of the second optical signal is different from a wavelength of the first optical signal.

An optical fiber amplification apparatus is disclosed, including an optical receiving port, a first optical output port, a second optical output port, a gain medium, a pump laser, reflection films, and a transmission-reflection film. The pump laser activates a function of the gain medium to amplify an optical signal. A multiplexed optical signal including a first-waveband optical signal and a second-waveband optical signal is incident onto the gain medium. The reflection films enable the multiplexed optical signal to be reflected back and forth in the gain medium. After the first-waveband optical signal reaches a first target gain, the first-waveband optical signal is output from the gain medium to the first optical output port. The second-waveband optical signal is amplified in the gain medium. After the second-waveband optical signal reaches a second target gain, the second-waveband optical signal is output from the gain medium to the second optical output port.

An optical fiber amplification apparatus is disclosed, including an optical receiving port, a first optical output port, a second optical output port, a gain medium, a pump laser, reflection films, and a transmission-reflection film. The pump laser activates a function of the gain medium to amplify an optical signal. A multiplexed optical signal including a first-waveband optical signal and a second-waveband optical signal is incident onto the gain medium. The reflection films enable the multiplexed optical signal to be reflected back and forth in the gain medium. After the first-waveband optical signal reaches a first target gain, the first-waveband optical signal is output from the gain medium to the first optical output port. The second-waveband optical signal is amplified in the gain medium. After the second-waveband optical signal reaches a second target gain, the second-waveband optical signal is output from the gain medium to the second optical output port.

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.

In a system for converting digital data into a modulated optical signal, an electrically controllable device, including a modulator having one or more actuating electrodes, provides an analog-modulated optical signal that is modulated in response to output data bits of a digital-to-digital mapping. A digital-to-digital conversion provides the mapping of input data words to the output data bits. The mapping enables adjustments to correct for non-linearities and other undesirable characteristics, thereby improving signal quality.

A fiber applied to an optical amplifier, where the fiber includes a rare earth-doped core and a cladding. The core includes a gain equalization unit. The core is configured to separately amplify optical signals of all wavelengths in a received multiplexing wave. The gain equalization unit is configured to equalize gains of the optical signals of all the wavelengths, such that gains of optical signals that are of all the wavelengths and that are transmitted from an egress port of the fiber all fall within a preset range, The gain of the optical signal of each wavelength in the optical signals of all the wavelengths is determined based on a ratio of power of an amplified optical signal to power of the unamplified optical signal.

A fiber applied to an optical amplifier, where the fiber includes a rare earth-doped core and a cladding. The core includes a gain equalization unit. The core is configured to separately amplify optical signals of all wavelengths in a received multiplexing wave. The gain equalization unit is configured to equalize gains of the optical signals of all the wavelengths, such that gains of optical signals that are of all the wavelengths and that are transmitted from an egress port of the fiber all fall within a preset range, The gain of the optical signal of each wavelength in the optical signals of all the wavelengths is determined based on a ratio of power of an amplified optical signal to power of the unamplified optical signal.

Systems to extend signal transfer used with a camera device comprise a first location station with a first receiver and a second receiver. The first receiver receives wireless signals from a user device that are changed and sent through a fiber optic cable to a second location station. The second receiver receives signals through the cable from the second location station, which signals are changed to wireless signals output to a user device. The second location station comprises a third receiver that receives from the cable from the first location station, which signals are changed to wireless signals output to a camera device. The second location comprises a fourth receiver that receives wireless signals from the camera device, which signals are changed at the first location to signals sent through the cable from the second location station to the first location station.