As for the high precision positioning of underwater targets, the GPS sonobuoy technique has two bottlenecks: high precision system clock synchronization and high accuracy time delay estimation.

• 为了实现水下载体高精度的定位，GPS声纳浮标需解决两个方面的技术难点：高精度的系统时钟同步和定位信号的高精度时延估计。