我们通常所说的频响函数 (Frequency Response Function，FRF)，它是结构的输出响应和输入激励力之比。 我们同时测量激励力和由该激励力引起的结构响应（这个响应可能是位移、速度或加速度），将测量的时域数据通过 快速傅立叶变换 （FFT）从时域变换到频域，经过变换，频响函数最终呈现为复数形式，包括实部与虚部，或者是幅值与相位。 很多时候，为方便起见，我们将频响函数写成部分分式形式. 我们常用矩阵形式来处理频响函数，所以用下标可以方便地确定某个输 …

2010年9月15日 · • The FRF can be used to find the steady-state response of a system to a sinusoidal input since, if e(t) y(t) G(s) and e(t) = sin2t, |G(2j)| = 0.3, G(2j) = −80 , then the steady-state output is y(t) = 0.3sin(2t − 80 ) ⇒ The FRF clearly shows the magnitude (and phase) of the re­ sponse of a system to sinusoidal input

In signal processing and electronics, the frequency response of a system is the quantitative measure of the magnitude and phase of the output as a function of input frequency. [1] .

The gain or amplitude response to the system (1) is a function of w. It tells us the size of the system’s response to the given input frequency. If the amplitude has a peak at wr we call this the practical resonance frequency. If the damping b gets too large then, for the system in equation (1), there is no peak and, hence, no practical ...

Frequency response is measured using the FFT, cross power spectral method with broadband random excitation. Broadband excitation can be a true random noise signal with Gaussian distribution, or a pseudo-random signal of which the amplitude distribution can be …

2024年7月7日 · 具体公式为：FRF = |Pxy (f)| / |Pxx (f)|，其中Pxy (f)为互功率谱，Pxx (f)为输入信号的自功率谱。 确保数据质量：数据质量直接影响计算结果，因此要确保数据采集和预处理过程的准确性。 选择合适的方法：根据系统特性和应用场景，选择合适的频响函数计算方法。 考虑噪声影响：在实际应用中，噪声会对计算结果产生影响。 因此，在计算过程中要尽量减小噪声的影响。 总之，计算频响函数是分析系统频率响应特性的重要手段。 通过掌握计算方法，我们可以更 …

A frequency response function (FRF) is a transfer function, expressed in the frequency-domain. Frequency response functions are complex functions, with real and imaginary components. They may also be represented in terms of magnitude and phase. A frequency response function can be formed from either measured data or analytical functions.

2009年10月19日 · The following article will attempt to explain the basic theory of the frequency response function (FRF). This basic theory will then be used to calculate the frequency response function between two points on a structure using an accelerometer to measure the response and a force gauge hammer to measure the excitation.

2024年8月19日 · Gain from a Frequency Response Function The gain is simply the magnitude of the FRF Gain = | G (j ω) | = | Y (j ω) | | X (j ω) | Where Y (j ω) and the X (j ω) are the numerator and denominator of G (j ω) respectively. The gain expression can be used to determine what the amplitude of the output signal would be at a particular frequency 12 ...

To estimate the FRF: Open a signal file. Choose Modules > Frequency Response Estimation from the menu bar. The FRF dialog box is displayed. The left half of the dialog box manages the Source signal, and the right half manages the Recevier signal.