PAM Waveform Design for Joint Communication and Sensing Based on Visible Light

In this paper, we propose a joint communication and sensing (JCAS) waveform design method for pulse amplitude modulation (PAM) signal based on visible light. Common communication and sensing performance metrics, including symbol error rate, achievable transmission rate, miss detection probability and Kullback-Leibler (KL) divergence are adopted. We provide an optimization criterion with respect to parameter of the integrated waveform under peak power constraint to balance the communication performance and the sensing performance. We conduct the JCAS experiments for the objects under short distance of 1 meter and long distance of 7 meters. Both numerical and experimental results show that, for PAM signals, there exists a fundamental tradeoff between the communication performance and the sensing performance. Given the same sampling rate and the same number of samples for target detection, high-order PAM signals provide better sensing performance due to the lower tail probability. Moreover, with longer distances and stronger diffuse reflections, the detection duration needs to be extended to obtain better sensing performance.