BMFLC幅相补偿的舰船升沉测量方法

BMFLC amplitude and phase compensation for ship heave measurement method

在利用捷联式惯性导航系统进行升沉测量的过程中,引入数字高通滤波器可以很好地解决高度积分发散的问题,但随之会带来由高通滤波器固有特性导致的幅值衰减和相位超前。基于此,定量地分析了高通滤波器引起的幅相误差,提出一种基于带限傅里叶线性组合(BMFLC)幅相补偿的升沉测量方法,并在BMFLC中引入遗忘卡尔曼滤波权值更新策略。在提高BMFLC拟合精度的基础上,进一步提高对数字高通滤波器输出信息的幅相误差补偿精度。最后利用六自由度运动平台和舰船实验验证所提方法,实验结果表明:所提方法测得的升沉位移均方根误差约为8.1 mm,具有较高的适用性和稳定性。

In the process of heave measurement by using strapdown inertial navigation system,the introduction of digital high-pass filter can solve the problem of high integration divergence well,but it will bring amplitude attenuation and phase advance caused by the inherent characteristics of the high pass filter.Therefore,the amplitude and phase errors caused by high-pass filters are quantitatively analyzed,and a heave measurement method based on bandlimited multiple Fourier linear combiner(BMFLC)amplitude and phase compensation is proposed.The forgetting Kalman filter updating weight strategy is introduced in BMFLC.On the basis of improving the fitting accuracy of BMFLC,the compensation accuracy of amplitude and phase errors for the outputting information of digital high-pass filters is further improved.Finally,the proposed method is validated by using a six degree of freedom motion platform and ship experiments.The experimental results show that the root mean square error of the heave displacement measured by the proposed method is about 8.1 mm,which has high applicability and stability.