What are the methods for describing the time domain and frequency of sensor signals?

describesensorThe process of signal variation usually involves two methods: time-domain and frequency-domain. The time-domain description of a signal mainly reflects the relationship between the amplitude of the signal and its variation over time. Correspondingly, the time-domain analysis method for a testing system also directly analyzes the time variable function or sequence. Study the time response characteristics of the system. The frequency domain analysis method describes the time domainsignalTransform and use frequency as an independent variable to study the structure of signals and the amplitude and phase relationships of various frequency components from the perspective of frequency distribution.

Generally speaking,传感器The form of time signals is usually complex, and it is often difficult, sometimes even impossible, to directly analyze the transmission of various signals in a testing system. Therefore, complex signals are often decomposed into the sum of certain specific types of basic signals, which should satisfy certain mathematical conditions and be easy to implement and analyze. The commonly used basic signals include sine signals, complex exponential signals, step signals, impulse signals, etc. The frequency description of a signal is to transform a time-domain signal into a frequency-domain signal, decompose the signal into a series of basic frequency-domain expressions according to the requirements of task analysis, and study the structure of the signal and the amplitude and phase relationships of various frequency components from the perspective of frequency-domain distribution. Decomposing a complex signal into the sum of a series of fundamental signals is particularly advantageous for analyzing a linear time invariant system. that is because传感器The response caused by multiple basic signals acting on such a system is equal to the sum of the responses generated by each basic signal acting alone.

The use of time-domain and frequency-domain methods to describe signals and analyze systems depends entirely onelementThe needs of different testing tasks. Time domain description intuitively reflects the variation of signals over time, while frequency domain description focuses on describing the frequency components of signals. But regardlessdeviceWhich description method should be used? The same signal contains the same amount of information, and different methods will not increase or decrease the information content of the original signal. For example, a periodic square wave can be seen as a superposition of sine waves of varying series, and the waveform decomposition method vividly expresses the time-domain and frequency-domain descriptions of periodic square waves and their relationship.