Simulink Reference

Discrete State-Space

Implement a discrete state-space system

Library

Discrete

Description

The Discrete State-Space block implements the system described by

where u is the input, x is the state, and y is the output. The matrix coefficients must have these characteristics, as illustrated in the following diagram:

• A must be an n-by-n matrix, where n is the number of states.
• B must be an n-by-m matrix, where m is the number of inputs.
• C must be an r-by-n matrix, where r is the number of outputs.
• D must be an r-by-m matrix.
  
  

The block accepts one input and generates one output. The input vector width is determined by the number of columns in the B and D matrices. The output vector width is determined by the number of rows in the C and D matrices.

Simulink converts a matrix containing zeros to a sparse matrix for efficient multiplication.

Data Type Support

The Discrete State Space block accepts and outputs a real signal of type double.

Parameters and Dialog Box

A, B, C, D

The matrix coefficients, as defined in the preceding equations.

Initial conditions

The initial state vector. The default is 0. Simulink does not allow the initial states of this block to be inf or NaN.

Sample time

The time interval between samples. See Specifying Sample Time in the online documentation for more information.

The State properties pane of this block pertains to code generation and has no effect on model simulation. See "Block States: Storing and Interfacing" in the Real-Time Workshop documentation for more information.

Characteristics

Direct Feedthrough	Only if D 0
Sample Time	Specified in the Sample time parameter
Scalar Expansion	Yes, of the initial conditions
States	Determined by the size of A
Dimensionalized	Yes
Zero Crossing	No

Discrete Filter

Discrete-Time Integrator

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