In this paper, we demonstrate a novel concept of collision avoidance based on single photon detectors along with time correlated single photon counting techniques, which uses chaotic pulse position modulation for anti-crosstalk considerations. In order to distract the signal from estimated background noise, parameters including pulse rate, discrimination threshold and number of accumulated pulses have been thoroughly analyzed based on the detection requirements, resulting in specified receiver operating characteristics curves. Both simulation and indoor experiments were performed to verify the excellent anti-crosstalk capability of the presented collision avoidance LIDAR despite of ultra-low transmitting power.
Chaotic pulse position modulation (CPPM) has been successfully used in robust digital communication for years. We propose to adapt CPPM for laser detection of remote targets to address the issue of noise. Specified in a time-of-flight (TOF) consecutive laser ranging application scenario, the feasibility of laser detection applying CPPM for laser detection is experimentally investigated. The scheme including the adaptive design for laser detection and parameter settings with validation is introduced. Lab-based electrical experiment and a proof-of-concept outdoor TOF experiment are further conducted to verify the feasibility of laser ranging and detection using CPPM through comparison with traditional Lidar detection and other pulse interval patterns. According to experiments and the following analysis, laser ranging using CPPM is feasible and more robust than traditional laser ranging.