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List of the table of contents of this article:

• 1, How to calculate the amplitude and phase characteristics of the signal and the system
• 2, What are frequency characteristics, amplitude characteristics and phase frequency characteristics?
• 3、What is the amplitude characteristic of the critical stable system
• 4, amplitude and frequency characteristics and phase frequency characteristics (in the signal and system, I hope a little popular explanation, thank you)
5, What is the amplitude phase characteristic, and what is the difference between it and the amplitude frequency characteristic?
• 6. Characteristics of the amplitude and frequency characteristics of the four networks

How to calculate the amplitude and phase characteristics of the signal and the system?

If the phase characteristic is φ(ω), then: tanφ(ω)=(4ω^2-120)/(8ω-ω^3)s is replaced by jω Substitute, ω is the angular frequency, and j is the imaginary unit.

G(jω) is called the frequency characteristic, and A(ω) is the ratio of the amplitude of the output signal to the amplitude of the input signal, which is called the amplitude frequency characteristic.

Amplitude and frequency characteristics are to describe the law that the amplitude of the input signal is fixed and the amplitude of the output signal changes with the change of frequency, that is, Au(jω)=V0Vi=V0Viejφ=Au(ω)ejφ(ω) In the formula, Au(ω) represents the relationship between the size of the voltage amplification multiple and the frequency. It is called amplitude and frequency characteristics.

The frequency characteristics of the stable system can be determined by experimental methods, that is, adding sinusoidal signals of different frequencies to the input terminal of the system, and then measuring the steady-state response output of the system, and then making the frequency characteristic curve of the system according to the amplitude characteristics and phase frequency characteristics.

s is replaced by jω, ω is the angular frequency, and j is the imaginary unit. The whole formula becomes a complex number with ω. The expression of the modulus value of this complex number about ω is the amplitude frequency characteristic A (ω), and the expression of the complex angle about ω is the phase frequency characteristic φ (ω).

What are frequency characteristics, amplitude characteristics and phase frequency characteristics?

1. The basic concept of frequency characteristics: Under the action of a sinusoidal signal, when the frequency of the system input changes from 0 to , the law of the amplitude and phase difference between the steady-state output and the input. The frequency of steady-state output is the same as that of input, only the amplitude and phase are different.

2. G(jω) is called frequency characteristic, and A(ω) is the ratio of the amplitude of the output signal to the amplitude of the input signal, which is called amplitude and frequency characteristic.

3. Frequency characteristics means that in the AC circuit, when the frequency of the input voltage changes, the load impedance will also change, so that it has different amplitude and frequency characteristics and phase frequency characteristics, and has different effects on the signals of different frequencies. This change relationship is the frequency characteristic.

4. 3 definitions of frequency characteristics Definition I: amplitude ratio, phase angle difference Define the amplitude ratio of the output signal to the input signal as amplitude characteristic, and the phase difference is the phase frequency characteristic. Frequency characteristics describe the ability of the system to transmit sinusoidal signals at different frequencies. Definition one has certain physical significance.

5. Geometric representation method: It seems that this noun is not a standard name, and it takes a long time to know what you mean.Commonly used are Fourier transform images, Porter diagrams, phase curves, and Nichols diagrams.

What are the amplitude and frequency characteristics of the critical stability system

1. G(jω) is called the frequency characteristic, and A(ω) is the ratio of the amplitude of the output signal to the amplitude of the input signal, which is called the amplitude and frequency characteristic.

2. Only when the system is stable can there be a stable frequency output, so that there will be a frequency response.

3. The characteristic that the phase shift angle changes with frequency is called the phase frequency characteristic. Due to the existence of reactor elements in the amplification circuit, the signal amplification capacity of the amplification circuit for different frequency components is different, and the signals of different frequency components will also produce different phase shifts after passing through the amplification circuit.

Amplitude and frequency characteristics and phase frequency characteristics (in the signal and the system, I hope to have a more popular explanation, thank you)

G (jω) is called the frequency characteristic, and A (ω) is the output letter The ratio of the amplitude of the number to the amplitude of the input signal is called the amplitude frequency characteristic.

G(jω) is called frequency characteristic, and A(ω) is the ratio of the amplitude of the output signal to the amplitude of the input signal, which is called amplitude and frequency characteristic. Φ (ω) is the difference between the phase angle of the output signal and the phase angle of the input signal, which is called the phase frequency characteristic. The characteristic that the phase shift angle changes with frequency is called the phase frequency characteristic.

Question 1: The principle of automatic control, how are the amplitude frequency and phase frequency characteristics in the figure calculated? Thank you for your explanation.. That is to replace the s of the passing function with jw. J is an imaginary unit (like i in mathematics, j is usually used in engineering), and w is the angular frequency of the sinusoidal signal.

Amplitude-frequency characteristics and phase-frequency characteristics in the op-amp. In the amplifier, the relationship between the amplification multiple and the frequency is: ω in the formula indicates the relationship between the size of the voltage amplification multiple and the frequency, which is called the amplitude-frequency characteristic. Amplitude-frequency characteristics are divided into low-pass, high-pass, band-pass, band-resistance and full-pass.

What is the amplitude phase characteristic, and what is the difference between it and the amplitude frequency characteristic?

1. The expression of the analog value of this complex number about ω is the amplitude characteristic A (ω), and the expression of the complex angle about ω is the phase characteristic φ (ω).

2. Different definition: amplitude-frequency characteristic is the characteristic that the amplitude of the output signal changes with the frequency of the input signal, and the phase-frequency characteristic is the characteristic that the phase of the output signal changes with the frequency of the input signal. The influencing factors are different: the amplitude characteristics are affected by the resistive elements, and the phase characteristics are affected by the resistive elements and the time constant.

3. The amplitude-frequency characteristic is the relationship between the amplitude-value ratio and the frequency. The amplitude-value ratio is the ratio between the dynamic response and the static response of the system such as the measurement system or spring; the phase-frequency characteristic is the relationship between the lag angle and the frequency, which is the relative error of forced vibration, that is, the dynamic and static response time error.

4. G(jω) is called frequency characteristic, and A(ω) is the ratio of the amplitude of the output signal to the amplitude of the input signal, which is called amplitude and frequency characteristic. Φ (ω) is the difference between the phase angle of the output signal and the phase angle of the input signal, which is called the phase frequency characteristic.The characteristic that the phase shift angle changes with frequency is called the phase frequency characteristic.

5. G (jω) is called frequency characteristic, and A (ω) is the ratio of the amplitude of the output signal to the amplitude of the input signal, which is called amplitude and frequency characteristic.

6, s is replaced by jω, ω is the angular frequency, and j is the imaginary unit.

Characteristics of amplitude and frequency characteristics of four networks

The following is a description of the amplitude and frequency characteristics of four common networks: Low-pass filter: The transmission function of the low-pass filter has a high gain at low frequency, and at high frequency It has a low gain. Therefore, low-pass filters can only retain low-frequency signals by filtering high-frequency signals.

Sweeping method; continuous shock pulse generation, find the amplitude envelope line obtained by its impulse response;Point frequency method; similar to the frequency sweep method, but the impact calculation of discrete frequency points; the phase frequency characteristic is the relationship between the lag angle and the frequency, which is the relative error of forced vibration, that is, the dynamic and static response time error.

Characteristics of the progressive amplitude and frequency characteristics of each typical link: When the movement of the system reaches the steady state, when comparing the steady-state component of the output and the input waveform, it can be found that the frequency of the steady-state output is the same as the input frequency, but the amplitude and phase of the output quantity are different from the input quantity.

G(jω) is called frequency characteristic, and A(ω) is the ratio of the amplitude of the output signal to the amplitude of the input signal, which is called amplitude and frequency characteristic. Φ (ω) is the difference between the phase angle of the output signal and the phase angle of the input signal, which is called the phase frequency characteristic. The characteristic that the phase shift angle changes with frequency is called the phase frequency characteristic.