在分析各种水下地形测量方法及其特点的基础上,提出应用互相关超声波测距方法进行水下微地形高程数据测量。通过发射信号与回波信号进行互相关运算精确捕捉回波信号的到达时刻以实现高程数据的测量。设计一种以单探头单波束超声波测距为基础的水下微地形测量系统,并分析信号处理电路和数字信号处理方法。对不同地形和不同底质的地形进行高程数据测量,对海底模拟地形进行探测与重构。研究结果表明:经过时间增益控制和滤波处理后的信号所含有的噪声和混响信号得到了抑制;应用互相关超声波测距方法得到的高程数据误差在-1~1 cm以内;生成的微地形图真实地反映了被测地形的地貌特征。
Based on analyzing various methods of detecting underwater topography, a new method of measurement elevation data of underwater micro-topography based on correlation ultrasonic range was proposed. To achieve precise elevation data, the time-delay was obtained by correlation operation sending wave and receiving wave. A system of detecting underwater micro-topography based on single-probe single-beam ultrasonic wave was designed. The signal processing circuit and data signal processing method were emphatically analyzed. The elevation data of various terrains with different stuffs and figures were measured. The stimulant seabed terrain was detected and reconstructed. The results show that the extent of reverberation and noise is small. The error of elevation data gained by correlation ultrasonic range is from -1 cm to 1 cm. The micro-topography map reconstructed really reflects the characters of the terrain detected.