Design and Performance Analysis of Intra-Vehicle VLC System With Random Receiver Orientation

Visible light communication is a promising technology for communication in an intra-vehicle scenario which can support high throughput without causing any electromagnetic interference. In contrast to RF link, the VLC link is not isotropic, i.e., it highly depends on the line of sight links (LOS). Therefore, it is important to understand the impact of receiver orientation and user mobility on the performance of VLC system. In the first part of the work, the effect of receiver orientation on the LOS channel is explored. The receiver orientation is modeled as a truncated Gaussian distribution. Based on the statistics of receiver orientation, channel and received signal to noise ratio (SNR) statistics are obtained for both the single input single output (SISO) and multiple input single output (MISO) systems. For the SISO system, closed-form expression for the bit error rate (BER) and outage probability are obtained. For the MISO VLC system, the BER and outage probability are evaluated numerically. The impact of Field of View (FOV) which corresponds to the aperture on the receiver from the transmitter on the performance metrics such as outage probability and BER are analyzed. To capture the impact of mobility on the performance of the system, random way-point mobility model is considered. Closed-form expression for the PDF of the LOS channel gain and BER is derived under the condition of angular variations are more dominant than the overall radial-gain spread for a coherence-period. The derived results help to explore the joint impact of random receiver orientation and mobility on the performance.