Apparatus and method for optical wireless communication based on color M-ary frequency shift keying

A method for operating an optical signal reception apparatus, the method comprising:

• by a camera, producing an image frame obtained by capturing a color LED transmitting a color modulated signal produced by an optical signal transmission apparatus;
• and
• by a processor, producing a color code data signal corresponding to the color modulated signal by demodulating, based on a bit-color mapping table set in advance, color information of the color LED in the image frame;
• and
• by the processor, producing a data stream by demodulating the color code data signal,
• wherein the color modulated signal is produced by separating at least part of the data stream into three channels, converting, into bits, level signals at an identical location in a time axis in a plurality of FSK modulated signals obtained by respectively modulating the separated data streams according to an M-ary frequency shift keying (M-FSK) scheme, and concatenating the bits.

An optical signal reception apparatus, the apparatus comprising:

• a camera configured to produce an image frame obtained by capturing a color LED transmitting a color modulated signal produced by an optical signal transmission apparatus;
• and
• a processor configured to extract grayscale level information of the color LED from the image frame so as to produce an FSK modulated signal, extract a frequency by performing Fourier transform on the FSK modulated signal, and produce a data stream by demodulating the FSK modulated signal based on a bit-frequency mapping table set in advance and the frequency,
• wherein the color modulated signal is produced by separating at least part of the data stream into three channels, converting, into bits, level signals at an identical location in a time axis in a plurality of FSK modulated signals obtained by respectively modulating the separated at least part of the data streams according to an M-ary frequency shift keying (M-FSK) scheme, and concatenating the converted bits.