4 symmetrical depth sounding
59-701 sounding systems
acoustic (echo) sounding
Acoustic depth sounding
Acoustic Sounding
声学探测
声波探测
声波测深
听音测深
声波探测技术
音响测深
回声测深
声测
声[波探]测
acoustical depth sounding
Airborne Laser Sounding
airborne laser sounding system
atmospheric humidity sounding
Atmospheric sounding in upper air
atmospheric sounding projectile
atmospheric sounding technology
audio-frequency magnetotelluric sounding method