A sensor on the aircraft records the time it takes to receive the backscattering of pulses, and that is used to compute distances to the forest canopy and to the soil beneath.

这架飞机上的一个探测设备记录下它收到脉冲反向散射所需时间而且这个时间可用于计算到森林树冠层和到树冠层下土壤的距离，以此而计算出树干高度。

youdao

During a forest survey, an aircraft-borne lidar sweeps a beam that fires about 70,000 pulses a second over the canopy.

在一次森林调查期间，从一架飞机负载的激光雷达上扫射出一束发出大约一秒7万次脉冲的红外光从树冠层上穿过。

youdao

During a forest survey, an aircraft-borne lidar sweeps a beam that fires about 70, 000 pulses a second over the canopy.

在一次森林调查期间，从一架飞机负载的激光雷达上扫射出一束发出大约一秒7万次脉冲的红外光从树冠层上穿过。

youdao

During a forest survey, an aircraft-borne lidar sweeps a beam that fires about 70, 000 pulses a second over the canopy.

ECONOMIST: Forest conservation