Abstract: A system, a non-transitory computer readable media and a method for FIR filtering. The method may include obtaining a set of input samples; and concurrently applying a FIR filtering process on the set of input samples to provide a set of FIR filtered output samples. The latter may include calculating intermediate results that represent a first number of coefficient-input sample products, while calculating only some of the first number of coefficient-input sample products, wherein the calculating of the intermediate results is executed by using less than a first number of multipliers.

Abstract: A method for phase correction, the method may include generating in parallel and by a set of phase error detectors, a set of phase error detection results (PEDRs) related to a set of blocks of digital samples, the digital samples are frequency corrected and represent optical signals conveyed over a coherent optical communication link; wherein the PEDs introduce PED noise that is indifferent to phase errors of the set of the blocks of digital samples; sending, in a sequential manner, the set of PEDRs, to a loop that comprises a loop filter; generating, by the loop, phase difference results, wherein each phase difference result is indicative of a phase difference between a certain PEDR of the PEDRs and a loop filtered PEDR generated by filtering a PEDR that precedes the certain PEDR; and processing, by a phase correction unit, the digital samples and the phase different results, to provide phase corrected digital samples.

Abstract: A method for signal reconstruction, the method may include obtaining, an input digital signal that is a digital representation of an received optical signal, wherein the received optical signal represents a transmitted optical signal that was transmitted by a coherent transmitter and over a channel to a coherent optical receiver; wherein a phase difference between the transmitted optical signal and the received optical signal is unknown; and generating a hybrid estimation, wherein the hybrid estimation represents a magnitude of the transmitted optical signal and a phase of the received optical signal.

Abstract: A system, a non-transitory computer readable media and a method for FIR filtering. The method may include obtaining a set of input samples; and concurrently applying a FIR filtering process on the set of input samples to provide a set of FIR filtered output samples. The latter may include calculating intermediate results that represent a first number of coefficient-input sample products, while calculating only some of the first number of coefficient-input sample products, wherein the calculating of the intermediate results is executed by using less than a first number of multipliers.

Abstract: 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.

Abstract: 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.