| Popis: |
Recently, OFDM has been considered for VLC to boost data rates and combat inter-symbol interference. However, VLC-OFDM inherits the disadvantage of high PAPR from traditional RF systems. Unlike RF signaling, both the maximum and minimum of VLC signals must be considered. Additionally, in order to support dimming control, the positive and negative dynamic-range constraints could be asymmetric. Clipping is the simplest way to satisfy the dynamic-range constraints, but it does not allow for any EVM distortion control. In this paper, we use the constrained clipping method which can mitigate the distortions so that the clipping levels can be more aggressive than the simple clipping to further reduce the PAPRs. Numerical results validate the proposed constrained clipping technique. |
