数字闭环光纤陀螺频率特性分析与测试

系统的闭环带宽严重影响光纤陀螺在振动、急转弯等环境条件下的测试精度，闭环光纤陀螺的实际带宽高达几kHz，无法采用一般的角振动台进行全频带频率特性测试，因此，频率特性的分析与测试成为了闭环光纤陀螺研究的一项重要内容。针对这种需求，根据系统的结构框图及工作原理，建立了数字闭环光纤陀螺的动态模型，推导出了系统的传递函数；在此基础上对数字闭环光纤陀螺的频率特性进行了分析，指出了改善系统动态特性的方法；最后，利用数字闭环光纤陀螺的闭环工作原理，通过在反馈阶梯波上直接叠加激励信号，实现了光纤陀螺阶跃响应和频率响应的测试，得出了系统闭环带宽高达9kHz的结论。

Testing and analyzing for frequency characteristics of digital closed-loop FOG

The performances of FOG under the circumstances of vibration or abrupt swerve were badly influenced by its closed-loop bandwidth. The actual bandwidth of a closed-loop FOG can reach several kHz,which is too high to be tested with an angle vibrator. So it is important to test and analyze the frequency characteristics of the digital closed-loop FOG. In view of this requirement,a dynamic model for digital closed-loop FOG was established based on its block diagram of configuration and principle,and the transfer function was deduced. Then the frequency characteristics of the digital FOG were analyzed,and a method to improve the dynamic characteristic of FOG was given. At last,the step response and frequency response were tested by adding signal to the digital phase ramp based on the principle of closed-loop FOG. The test result shows that the bandwidth of the closed FOG is up to 9 kHz.