An electro-absorption modulator (EAM) comprising an integrated high speed electro-optical control loop for very high-speed linearization and temperature compensation for analog optical data center interconnect applications is disclosed. The control loop can function in a stable manner because the electronics and optical components are monolithically integrated on a single substrate in small form factor. Because of the small size enabled by monolithic integration, the temperatures of the optical blocks and electronics blocks are tightly coupled, and the control loop time delays and phase delays are small enough to be stable, even for very high frequency operation. This arrangement enables a low cost, low power analog transmitter implementation for data center optical interconnect applications using advanced modulation schemes, such as PAM-4 and DP-QPSK.

An electro-absorption modulator (EAM) comprising an integrated high speed electro-optical control loop for very high-speed linearization and temperature compensation for analog optical data center interconnect applications is disclosed. The control loop can function in a stable manner because the electronics and optical components are monolithically integrated on a single substrate in small form factor. Because of the small size enabled by monolithic integration, the temperatures of the optical blocks and electronics blocks are tightly coupled, and the control loop time delays and phase delays are small enough to be stable, even for very high frequency operation. This arrangement enables a low cost, low power analog transmitter implementation for data center optical interconnect applications using advanced modulation schemes, such as PAM-4 and DP-QPSK.

An electro-absorption bias circuit may include a temperature sensor. The electro-absorption bias circuit may include a controller to provide a temperature-dependent control signal based on data received from the temperature sensor. The electro-absorption bias circuit may include a power supply to provide an output voltage based on the temperature-dependent control signal from the controller. The electro-absorption bias circuit may include an electro-absorption driving circuit to output a bias voltage applied to the output voltage provided by the power supply.

A pluggable optical module includes a pluggable electric connector, a control unit, an optical signal output unit, and a pluggable optical receptor. The pluggable electric connector can communicate a modulation signal and a control signal with an optical communication apparatus. The optical signal output unit outputs an optical signal modulated by the modulation scheme by the control signal in response to the modulation signal. The pluggable optical receptor is configured in such a manner that an optical fiber is insertable into and removable from the pluggable optical receptor. The pluggable optical receptor can output the optical signal output from the optical signal output unit. The control unit controls the optical signal output unit to output the optical signal of a modulation amplitude set corresponding to the modulation signal in the modulation scheme specified by the control signal.

Embodiments are disclosed for equalizing input signals for communication systems. An example method includes receiving an input signal. The input signal encodes a plurality of bits in a number of amplitude levels. The example method further includes converting the input signal to an equalized output signal using a plurality of lookup table circuits. The equalized output signal encodes a plurality of symbols in a number of amplitude levels. The example method further includes feeding the equalized output signal to an output driver circuit.

An integrated high speed electro-optical control loop for very high-speed linearization and temperature compensation of an electro-absorption modulator (EAM) for analog optical data center interconnect applications is disclosed. The control loop can function in a stable manner because the electronics and optical components are monolithically integrated on a single substrate in small form factor. Because of the small size enabled by monolithic integration, the temperatures of the optical blocks and electronics blocks are tightly coupled, and the control loop time delays and phase delays are small enough to be stable, even for very high frequency operation. This arrangement enables a low cost, low power analog transmitter implementation for data center optical interconnect applications using advanced modulation schemes, such as PAM-4 and DP-QPSK.

Embodiments are disclosed for equalizing input signals for communication systems. An example method includes receiving an input signal. The input signal encodes a plurality of bits in a number of amplitude levels. The example method further includes converting the input signal to an equalized output signal using a plurality of lookup table circuits. The equalized output signal encodes a plurality of symbols in a number of amplitude levels. The example method further includes feeding the equalized output signal to an output driver circuit.

An optical converter is to be simply and reliably monitored. Thereto, a circuit device including a measurement bridge with a measurement branch, a first comparison branch and a second comparison branch is provided. A conductor path loop of the converter can be integrated in the measurement branch. The first comparison branch has a first series resistance variable via a first active element. Similarly, the second comparison branch has a second series resistance variable via a second active element. The first and the second active elements are respectively controllable by the same control signal. The circuit device further has an evaluation circuit with a first comparator and a second comparator, the outputs of which form the control signal and at the same time an output signal of the circuit device in AND-gated manner. Each comparator compares a tap of its respective comparison branch to a tap of the measurement branch.

An integrated high speed electro-optical control loop for very high-speed linearization and temperature compensation of an electro-absorption modulator (EAM) for analog optical data center interconnect applications is disclosed. The control loop can function in a stable manner because the electronics and optical components are monolithically integrated on a single substrate in small form factor. Because of the small size enabled by monolithic integration, the temperatures of the optical blocks and electronics blocks are tightly coupled, and the control loop time delays and phase delays are small enough to be stable, even for very high frequency operation. This arrangement enables a low cost, low power analog transmitter implementation for data center optical interconnect applications using advanced modulation schemes, such as PAM-4 and DP-QPSK.

A system and method for a high-speed transmitter comprising a precoder configured to receive a sequence of input symbols and to generate for each received symbol a respective recoded symbol is disclosed. The transmitter includes a recoding unit configured for recoding each current received PAM-M based on the recoded symbol immediately preceding the current recoded symbol at the recoding unit, a shift unit configured for determining a shift value for each current received symbol from the recoding unit based on the symbol received from the recoding unit and immediately preceding the current symbol at the shift unit; and Feed-Forward Equalizer unit for applying the shift values to the respective symbols received from the recoding unit to generate a corresponding sequence of output symbols to be transmitted in an output stream.