Abstract: A digital communications system includes a transmitter and a receiver. The transmitter can integrate encoded digital signals by converting the encoded digital signals into integrated signals that are proportional to the time integral of the encoded digital signals. The transmitter can then transmit the integrated signals. The receiver can receive the integrated signals and thereafter differentiate the integrated signals into a representation of the encoded digital signals that is proportional to the rate of change of the integrated signals. By integrating the encoded digital signals at the receiver and thereafter differentiate the integrated signals at the receiver, the system can reduce electromagnetic emissions associated with the transmission of communications via a transmission medium.

Abstract: The method and associated apparatus of the present invention decodes optical signals by appropriately weighting the respective noise portions of the two phase segments generated by the photodetector, such as an APD, such that the optical signal can be reliably decoded. The photodetector detects an optical signal having a light portion and a dark portion. The photodetector then generates an electrical pulse in response to the optical signal. The electrical pulse has two phase segments, namely, one phase segment corresponding to the light portion of the optical signal and another phase segment corresponding to the dark portion of the optical signal. Each phase segment also includes a respective noise portion. The optical decoding method and apparatus determines a weighting factor based upon the respective noise portions of the two phase segments. Thereafter, at least one phase segment is weighted by the weighting factor. For example, the noisier phase segment can be attenuated by the weighting factor.