CPC H04B 10/116 (2013.01) [H04B 10/6931 (2013.01); H04B 10/697 (2013.01); H04L 7/048 (2013.01); H04B 10/60 (2013.01)] | 5 Claims |
1. A method of preprocessing an optical signal so as to filter out ambient light and accommodate for differences in signal level to enhance Visible Light Communication (VLC) operation, the method comprising:
detecting a light input via a photodetector and amplifying an output of the photodetector via a first amplifier and outputting an amplified detected signal representative of the light input, the light input having both the optical signal and the ambient light;
filtering out the ambient light of the amplified output of the photodetector and outputting a filtered signal, wherein the filtering removes portions of the detected signal that are not at a same modulation frequency as the optical signal; and
increasing an amplitude of the filtered signal in a second amplifier, the second amplifier being a variable amplifier that is controlled at variable gain settings by a controller based upon an an amplitude capture stage that captures an amplitude of the filtered signal.
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