High-repetition-frequency lidar echo signal acquisition technology for enhanced fire monitoring

To address the challenges of echo signal acquisition and temporal integration posed by the triple requirements of large dynamic range, high resolution and real-time processing in high-repetition-frequency lidar systems for forest fire prevention, we have developed a novel "Read-Accumulate-Store" IP architecture. This design enables parallel acquisition of signal and temporal integration, fulfilling the unique signal accumulation demands of lidar systems. Validation using standard signals superimposed with white noise demonstrated a 50 dB Signal-to-Noise Ratio (SNR) improvement after performing over 1,000 cumulative averages on 4,096 data points. Comparative evaluations with conventional acquisition systems revealed strong consistency in performance, with the proposed architecture exhibiting superior efficiency. Implemented in a 5 kHz scanning lidar system, the methodology was tested in fire smoke simulation experiments conducted in Yan'an, China. Artificial ignition points at 5.4 km and 8.1 km were continuously scanned by the lidar, with retrieved the peaks of depolarization ratio precisely aligning with the ignition locations, which confirmed the capability of the system to rapidly and accurately identify smoke sources. The proposed acquisition system features single-chip integration and eliminates the requirement for bulk storage. Key Integral parameters—including sampling frequency, data length, and channel count—are flexibly programmable, offering significant cost advantages for scalable deployment.