Signal and linear system analysis--basic knowledge

First, the basic introduction:

Signal and system is an important specialized basic course of electronic information, communication and electrical specialty, mainly study the basic theory, basic concept and basic system analysis method of signal and linear system analysis.

Second, the main points of knowledge:

1. A signal is a representation of information, often expressed as a time function or sequence, also expressed as a waveform.

2. Signal classification:

A. Identification of signals and random signals;

B. Continuous signals and discrete signals;

C. Periodic signals and non-periodic signals;

D. Real signal and reply number;

E. Energy signals and power signals;

Three, the signal to go through the operation

1. The simplest arithmetic;

2 transform (reversible) variable substitution, function image translation, inversion, scaling; it is the theory of picture flipping, video regression, image enlarging and shrinking;

3. (most important) convolution integral differential, Fourier transform, Laplace transform, z-transform;

Four, singular function

The signal and the linear system basically revolves around these singular functions, must grasp their play nature (the breach of exercise work, later will say) these singular functions will function our linear system, let us determine its response function; sampling, delay, integration, differential and other functions;

Five, the meaning of learning signals:

Signals and systems confuse signals with functions and systems, and functions can represent signals and represent a system. Learning the signal is to learn advanced mathematics, the essence lies in, the higher mathematics is entirely in mathematical theory operation derivation, and the signal can be on the basis of mathematics to give engineering meaning, the mathematics and physics together, a function represents a system, the system can be designed by the circuit, indicating that the signal can be real action on the system, and get response.

Vi. concept of the system

1. A number of interrelated, interacting things in accordance with a certain pattern of the combination of a specific function of the whole;

2. Classification: Time system and dynamic system, continuous system and discrete system, linear system and nonlinear system, variable system and constant system, stable and unstable system;

3. Signal class operations and exercises often let us determine whether a function (System) is a linear, time-varying, stable system

Signal and linear system analysis--basic knowledge