Effective interference mitigation scheme for multi-LED-based mobile optical camera communication.

Recently, optical camera communication (OCC) based on light-emitting diodes (LEDs) and complementary metal oxide semiconductor (CMOS) image sensors has received extensive attention due to its low cost and high flexibility. However, considering that the location of the user with a CMOS image sensor changes frequently, multi-LEDs are required to achieve seamless communication. In the paper, to mitigate random interchannel interference in overlapping areas of LED radiation, an effective identification recognition and sorting-based column selection are proposed. Meanwhile, to alleviate the distortion of bright and dark stripes caused by overlapping exposure time and user movement, an improved sampling scheme based on length estimation is proposed and experimentally demonstrated in a multi-LED-based mobile OCC system. Moreover, by varying the overlap rate of the adjacent LEDs' radiation area and the moving speed of the user, respectively, the performance of the system is investigated. The experimental results show that, the bit error rate (BER) performance of the system decreases slightly with the increasing of moving speed, but it is lower than the hard-decision forward error code rate limit. In addition, at the overlap rate of the LED radiation area of 4.3% and the moving speed of 80 cm/s, the BER is close to 10 using the proposed scheme.