关键词: 激光雷达, FPGA, 模数转换, 数据采集, 累加平均技术

Abstract:

Data acquisition equipment of lidar echo signal is the critical part of lidar system. In order to improve signal-to-noise ratio (SNR), data acquisition equipment should have the function of filtering and high-speed data accumulation. In order to meet the requirement of lidars with different repetition frequency, the parameters such as sampling depth and accumulating time should be reconfigurable. A universal data acquisition card of lidar echo signal (DAQ card) with a sampling rate of 20 MHz and reconfigurable parameters, which has the function of filtering and hardware accumulation, is realized by using FPGA as main control element. The test results show that the DAQ card achieves the basic parameter configuration function and accumulation function under the different repetition rate of the trigger signal, and the SNR is 71.9 dB. Compared with a foreign echo signal acquisition equipment, the DAQ card has longer detection range and higher SNR in high repetition frequency lidar.

Key words: lidar, FPGA, analog-digital conversion, data acquisition, accumulation-average technique