双基（机载）合成孔径雷达测高——比较没技术含量，因为用的方法是斜距差，没用相位差（还没研究出来），所以误差有点大。-Double-base (Airborne) synthetic aperture radar altimeter- not the technical content of comparison, because the methodology used is inclined away from the poor, no phase difference (not finding out), so a bit big error.