基于自适应带通滤波的航天器正弦扫频试验数据处理方法

为解决传统STFT(Short Time Fourier Transform)方法因非同步采样引起频谱泄漏,造成频域曲线幅值降低,产生较大误差的问题,提出一种基于频域带通滤波的数据处理方法,通过在频域逐次移动带通滤波器的中心频率,获得信号中各个频率分量幅值的最大值。利用该方法对某载人航天器搭载的力学参数测量系统在整器正弦振动试验中采集的数据进行频谱分析,结果表明,该方法可有效获取力学参数测量系统各测点的频率幅值曲线,减少传统STFT方法产生的能量泄漏的影响。研究成果也可用于不依赖振动控制仪或无COLA通道的数据采集系统正弦振动试验的数据处理。

Data processing method in sine swept test for spacecraft based on adaptive band-pass filter

The signal processing commonly relies on the vibration controller or the COLA (constant output level adaptor) data acquisition system in the sine vibration test for the manned spacecraft. For the mechanical parameter measurement system without the COLA function for the manned spacecraft, the traditional STFT(short time Fourier transform) method can result in a spectrum leakage due to the asynchronous sampling, thus the amplitude of frequency domain might be reduced and a major error might be produced. To solve the above problem, a data processing method based on the band pass filter in the frequency domain is proposed. The maximal values of the frequency components of the signal can be acquired by moving the center frequency of the band pass filter, and the spectrum analysis of the mechanical parameter measurement system in the sine vibration test for the manned spacecraft is acquired by the proposed method. It is shown that the proposed method can effectively acquire the spectrum at each measuring point of the mechanical parameter measurement system and the influence of the spectrum leakage by the traditional STFT method can be reduced. The research findings provide a reference for the signal processing method of the sine vibration test for the data sampling system independent of the vibration controller and without the COLA data acquisition system.