Methods for configuring an optical link in which a distribution of transmission data rates and line rates are configured for a predetermined amount of optical bandwidth to maximize transmission capacity. In these methods, a controller of an optical network obtains input parameters that include a signal-to-noise ratio (SNR) for optical signals and an allocated bandwidth of the optical link, further obtains, for each line rate, a mapping of transmission data rates along a frequency spectrum of the allocated bandwidth compatible with the SNR, and generates a channel plan in which a number of traffic modes and a distribution of a plurality of channels in the allocated bandwidth are set to maximize transmission capacity. The plurality of channels is used for transmitting the signals on the optical link. The controller configures at least one optical network element in the optical network to establish the optical link based on the channel plan.

Methods for configuring an optical link in which a distribution of transmission data rates and line rates are configured for a predetermined amount of optical bandwidth to maximize transmission capacity. In these methods, a controller of an optical network obtains input parameters that include a signal-to-noise ratio (SNR) for optical signals and an allocated bandwidth of the optical link, further obtains, for each line rate, a mapping of transmission data rates along a frequency spectrum of the allocated bandwidth compatible with the SNR, and generates a channel plan in which a number of traffic modes and a distribution of a plurality of channels in the allocated bandwidth are set to maximize transmission capacity. The plurality of channels is used for transmitting the signals on the optical link. The controller configures at least one optical network element in the optical network to establish the optical link based on the channel plan.

An optical communications system includes a modulator/demodulator (modem) to transmit outgoing communications data and to receive incoming communications data in a transceiver. A main detector is coupled to the modem to convert an optical signal representing the incoming communications data to an electrical signal for the modem. An adaptive data rate processor monitors the electrical signal from the main detector to determine a current power level for the optical signal. The adaptive data rate processor dynamically adjusts a data rate of the modem based on the determined current power level of the optical signal.

Aspects of the present disclosure describe distributed fiber optic sensing (DFOS) systems, methods, and structures that advantageously overcome problems encountered when operating DFOS systems over operational telecommunications facilities namely, cross-phase modulation, and uneven amplitude profiles through the use of a novel constant amplitude coded DFOS employing suppressed out-of-band signaling.

Sampling circuitry for receiving an analog signal from photodetector circuitry and generating a sample analog signal. Equalization circuitry for generating an equalized signal comprising first and second sample values corresponding with a cursor tap and a first postcursor tap, and one or more third sample values corresponding with taps other than the cursor tap and the first postcursor tap. In the equalized signal, amplitudes of the first and second sample values are substantially equal while the third sample values are attenuated relative to the first and second sample values. The first and second sample values correspond with two or more first symbols of a first alphabet. Data slicer and modulo circuitry to generate a data signal based on the equalized signal and perform a modulo operation on the two or more first symbols and to generate one or more second symbols. The second symbols are according to a second alphabet.

A method for allocating bandwidth to a first ONU, a second ONU, M.sub.1 ONUs, and M.sub.2 ONUs includes, during an allocation cycle, (i) granting a respective upstream time slot to, of a plurality of N ONUs, only each of the M.sub.1 ONUs, and (ii) granting a first upstream time slot to the first ONU. Each of the M.sub.1 ONUs and M.sub.2 ONUs is one of the plurality of N ONUs. The method also includes, during a subsequent cycle, (i) granting a respective upstream time slot to, of the plurality of N ONUs, only each of the M.sub.2 ONUs. The N ONUs includes a skipped-ONU that is one of either, and not both, the M.sub.1 ONUs and the M.sub.2 ONUs. The method includes, during the subsequent allocation cycle, granting a second upstream time slot to a second ONU, which is not one of the plurality of N ONUs.

A communication device effectively transmits high-speed data while being less affected by restrictions of an environment by adjusting a communication channel depending on an optical communication environment.

Systems and methods for constellation shaping using low rate loss bit-level distribution matchers include receiving blocks of input bits and, for each input block of a predetermined size, assigning a respective codeword of a predetermined output block size. The number of bits of a given bit value in the codeword is dependent on a predetermined target probability distribution. A one-to-one mapping exists between each possible combination of input bits and a codeword for input blocks containing the combination. Some codewords include a number of bits having the given bit value that is different than the predetermined target probability distribution, but an average number of bits having the given bit value in the available codewords meets the predetermined target probability distribution. The disclosed methods result in more available codewords and a lower rate loss than in bit-level distribution matchers with a constant modulus, while achieving similar shaping.

A high-speed optical receiver implemented using a low-speed light receiving element is provided, which is configured to receive an optical signal having a higher transmission rate than that received using a general avalanche photo diode (APD) by expanding a frequency bandwidth using a receiver circuit configured together with an APD in the optical receiver including the APD, an APD bias control circuit, a transimpedance amplifier (TIA) for amplifying a signal received from the APD to have low noise, and a post amplifier; and a method of implementing such a high-speed optical receiver.

A trans-impedance amplifier arrangement has an input configured to receive an output from a photo-detector, a current monitoring circuit configured in use to provide a current monitor signal dependent on a current through the photo-detector, and an output configured to output said current monitor signal to a control module, said output further configured to receive control information from said control module. A control module is configured to receive the current monitor signal and to provide the control information.