双曲线调频在高速水下目标航行参数遥测中的应用研究

Hyperbolic frequency modulated application in high-speed underwater target navigation parameters telemetry

对于高速、强机动的水下目标来说,其航行参数信息的实时遥测具有重要意义。水声信号的多普勒频移估计与补偿是水声遥测的关键技术之一,它直接影响着水声遥测的效果与性能。本文针对双曲线调频信号及线性调频信号进行仿真分析,对比在相同情况下的多普勒频移可补偿性,仿真实验证明双曲线调频信号具备较高的多普勒容限,其时延值估计精度可达到1μs。结合工程实际,本文采用双曲调频信号与单频信号组合的方式进行水声遥测,充分发挥双曲线调频信号的多普勒不变性和单频信号对多普勒频移的敏感性,在获得较高定位精度的同时,也具备高精度的水声遥测功能。该组合信标信号经过湖上试验验证,具有遥测精度高、误码率低、易于实现等优点,可应用于相关水声工程中。

For high-speed underwater target of strong maneuverability,the real-time telemetry of the navigation parameters is important.Doppler shift estimation and compensation of underwater acoustic signal is one of those key techniques for the underwater acoustic telemetry,which directly affects the effectiveness and performance of the telemetry.In this article,Doppler shift was calculated for both HFM and linear frequency modulation（LFM） signals,and the analyses and comparison in the same conditions were made.Simulation results show that HFM signal has higher Doppler tolerance,and the estimation accuracy for time delay can be achieved by 1μs.In practical applications,the HFM signal was combined with a single frequency signal for underwater acoustic telemetry.Thus,both the Doppler invariance of the HFM signal and the Doppler shift sensitivity of the single-frequency signal played important roles in obtaining high positioning accuracy to realize high-precision underwater acoustic telemetry.The effectiveness of this combined beacon signal has been verified through lake trial.The testing results show that the combined beacon signal has the characteristics of higher telemetry precision and lower error rate.It is easy to implement and can be applied in the relevant underwater acoustic engineering projects.