INS/GPS组合导航系统具有较高的导航定位精度,但在GPS信号失效时,导航定位误差会显著漂移。为解决此问题,提出了一种基于脉冲响应模型的GPS失效解决方法。首先,使用基于傅里叶基神经网络的频谱分析方法建立起INS系统机动信号与INS/GPS组合导航系统机动信号之间的频域传递函数;然后,将此频域传递函数转换到时域,得到时域脉冲响应模型;将得到的时域脉冲响应模型与INS机动信号卷积。将卷积之后的信号作为JNS/GPS组合导航系统在GPS信号失效时的过渡信号。仿真实验证明,该模型可以有效抑制INS/GPS组合导航系统在GPS信号失效时的定位误差漂移。
The INS/GPS system has high positioning accuracy,but its positioning error has a significant drift during the GPS outages. In order to solve this problem,an algorithm based on the impulse response model for bridging GPS outages was proposed. First of all,a frequency domain transfer function between the INS and the INS/GPS motion signals was established by use of a spectrum analysis method based on FBF(Fourier basis functions) neural network, then this frequency domain transfer function transformed to the time domain,and subsequently a time domain im pulse response model obtained. Finally,the convolution of the time domain impulse response model and the INS motion signals was used for bridging GPS outages. Simulation results prove that this impulse response model can effectively inhibit the positioning error drift of the INS/GPS system during GPS outages.