Performance Evaluation of ZCC and OZCZ Code Set in an Integrated VLCP-CDMA System

In this letter, we apply code division multiple access (CDMA) technology to an integrated visible light communication and positioning (VLCP) system, which can recover the original user data and obtain the positioning information simultaneously. The two unipolar code sets with flexible construction methods, zero cross correlation (ZCC) code set and optical zero correlation zone (OZCZ) code set, are adopted and evaluated in the proposed system. Compared with the traditional spreading code set, these two code sets can directly suit to the VLCP system with higher transmission efficiency. In addition, the results show that zero correlation properties of OZCZ code set can effectively overcome non-perfect synchronization effects in the quasi-synchronous (QS) system. In a space of 6 m $\times $ 6 m $\times $ 5 m, the bit error rate (BER) of $1.58\times {10^{-3}}$ and average positioning error of 2.73 cm are successfully achieved in the synchronous system, while the BER of $1.60\times {10^{-3}}$ and average positioning error of 3.62 cm are realized in the QS system.