宽带声学多普勒计程仪性能试验分析

Performance test and analysis of broadband acoustic Doppler velocity log

宽带声学多普勒计程仪与窄带声学多普勒计程仪相比,具有更高的测速精度和更广泛的应用价值。其中宽带信号的编码形式是提升宽带多普勒计程仪性能的重要因素。文章利用宽带测速的标准差公式分析了宽带多普勒测速精度的误差来源,提出了采用差分全球定位系统(Differential Global Positioning System,DGPS)和iXSEA公司的Octans光纤罗经组合测速参考系统进行测速精度考核的试验方法,分别对63、31和15阶(即码元数)的三种m码形式的编码序列脉冲,在高航速和低航速下,进行了对地和对水的测速考核试验以及数据分析。试验结果表明,宽带声学多普勒计程仪具有比传统计程仪测速精度高、稳定性好的特点。文章为宽带多普勒计程仪在实际应用中的参数选择提供了重要的试验依据。

Compared with narrow-band acoustic Doppler velocity log, broadband acoustic Doppler velocity log (DVL) has higher time resolution and velocity measurement accuracy, and so has wider application value. The broadband coding form is especially important for the performance of DVL. In this paper, the factors affecting the velocity ac- curacy are studied theoretically, and a test method using GPS and Octans combined reference system for evaluating the velocity accuracy of DVL is proposed. Under the condition of high speed and low speed, the tests and data analyses of the velocity measurements in both water and bottom modes are carried out with the m coding sequences of 63, 31 and 15 units respectively. The experimental results show that DVL has the characteristics of high accuracy and good stability, and this study provides an important experimental basis for the parameter selection of DVL in practical applications.