Analysis of Visible Light-Based ISAC Channel Characteristics in a V2V Scenario

In this paper, we investigate the visible light-based integrated sensing and communication (ISAC) channel characteristics in a vehicle-to-vehicle (V2V) scenario, focusing on monostatic sensing and bi-static sensing modes. The ISAC channel is divided into a target channel and a background channel. The channel impulse response (CIR) at different distances, as well as the fading characteristics, multipath correlation, and delay spread of the channel within the effective sensing distance in the two sensing modes are investigated by ray tracing simulation. The results show that with the increase of distance, the target channel received power ratio of mono-static sensing decreases by 30%, while the received power ratio of bi-static sensing is stable at about 1.06%, the target channel fading of mono-static sensing is faster than that of bi-static sensing. In addition, the linear fit coefficient of the root mean square (RMS) delay spread (DS) values for mono-static sensing is positive with a mean value of 2.95 which is greater than the mean value of 0.32 for the RMS DS values for bi-static sensing, while the linear fit coefficient of the RMS DS values for bi-static sensing is negative. Overall, the bi-static sensing system outperforms at longer distances, has a more stable target signal received power ratio, better handling target signals and background noise, reducing signal RMS DS, and improving transmission quality and anti-interference capabilities, indicating the advantages of bi-static sensing in V2V scenarios using visible light-based ISAC.