Influence of Reflected Light in Illumination-Light VN-CodeSK Based Positioning Systems

This paper evaluates the effect of reflected light on position error performance when measuring position in the Visible Light Communication (VLC) using the Variable N-parallel Code Shift Keying (VN-CodeSK) system. In particular, the trilateration method and optical fingerprinting method are discussed as positioning systems. Performance results are obtained by computer simulation on a well-known indoor room model. Consequently, it is shown that the trilateration method degrades more sensitively to reflected light than the optical fingerprinting method. The optical fingerprinting method is found to improve accuracy in some cases due to reflected light. In this room model, it is found that the effect of reflected light becomes smaller when the distance from wall is greater than 4[cm].