Efficient demodulation scheme based on adaptive clock extraction and mapping-sampling for a mobile OCC system.

An efficient demodulation scheme based on adaptive clock extraction and mapping-sampling is proposed and experimentally demonstrated for mobile optical camera communication (OCC) systems. For the proposed scheme, it can effectively improve the system performance in mobile OCC. The bit error rate (BER) performance of the proposed scheme and the other existing schemes are compared. The experimental results show that under the speed from 0.4 m/s to 0.7 m/s, it can significantly improve the system performance using the adaptive clock extraction and the mapping-sampling scheme in mobile OCC systems. Compared with the length estimation scheme, when the speed is 0.7 m/s, the BER can be improved from 9.14×10 to 3.16×10 at the exposure time of 1/12,000 s using the proposed scheme. In addition, the required memory and processing time of the proposed scheme are analyzed, which indicates that the proposed scheme has negligible influence on memory overhead and computational complexity.