Weighted-sum processing method and apparatus for decoding optical signals

A method of decoding optical signals comprising the steps of:

• detecting an optical signal having a light portion and a dark portion;
• generating a pulse having two phase segments in response to the detected optical signals, wherein one phase segment corresponds to the light portion of the optical signal and the other phase segment corresponds to the dark portion of the optical signal, and wherein each phase segment includes respective signal and noise portions;
• determining a signal weighting factor of less than 1 based upon the respective noise portions of the two phase segments;
• weighting the phase segment which has the noise portion with the greatest power by the signal weighting factor;
• and
• decoding the optical signal based upon the two phase segments as weighted by the signal weighting factor.

An optical detector for detecting and decoding an optical signal, said detector comprising:

• a photodetector for generating an electrical pulse in response to illumination thereof, wherein the electrical pulse has one phase segment generated during illumination of said photodetector, and another phase segment generated by said photodetector in the absence of light, and wherein each phase segment includes respective signal and noise portions;
• signal weighting factor determining means, responsive to said photodetector, for determining a signal weighting factor based upon the respective noise portions of the two phase segments;
• weighting means, responsive to said signal weighting factor determining means, for weighting the phase segment generated during illumination of said photodetector by the signal weighting factor;
• and
• a decoder, responsive to said weighting means, for identifying the optical signal based upon the two phase segments as weighted by signal weighing factor.