In this 7th part of the tutorial Modeling digital communication systems using Simulink we will explain shortly what Model Configuration Parameters is in Simulink.

The Model Configuration Parameters window allows the user to specify the simulation start and stop time and choose the solver for the simulation.

Let see first how to open the Model Configuration Parameters window. To open it in the Simulation tab and select Model Configuration Parameters. You should see the following,

The figure above shows the Model Configuration Parameters for your current simulink model in use.There you can see that the Type of solver is set to Variablestep and the Solver used the ode-45(Dormand-Prince), which, in general is the best first choice as a solver for most Simulink models.

By clicking on the Help button in the Model Configuration Parameters window, the MathWorks documentation describes several aspects of this window including:

• Solver choices

• Simulation and clock time are not the same

• Fixed-step and variable-step size

• Shortened simulation time with variable-step solver

For both fixed-step and variable-step solvers, the next simulation time is the sum of the current simulation time and the step size. Using a fixed-step solver,the step size remains constant throughout the simulation whereas use of a variable-step solver allows the step size to vary from step to step in accordance with the specified error tolerance.

The Model Configuration Parameters window allows the user to specify the simulation start and stop time and choose the solver for the simulation.

Let see first how to open the Model Configuration Parameters window. To open it in the Simulation tab and select Model Configuration Parameters. You should see the following,

The figure above shows the Model Configuration Parameters for your current simulink model in use.There you can see that the Type of solver is set to Variablestep and the Solver used the ode-45(Dormand-Prince), which, in general is the best first choice as a solver for most Simulink models.

By clicking on the Help button in the Model Configuration Parameters window, the MathWorks documentation describes several aspects of this window including:

• Solver choices

• Simulation and clock time are not the same

• Fixed-step and variable-step size

• Shortened simulation time with variable-step solver

For both fixed-step and variable-step solvers, the next simulation time is the sum of the current simulation time and the step size. Using a fixed-step solver,the step size remains constant throughout the simulation whereas use of a variable-step solver allows the step size to vary from step to step in accordance with the specified error tolerance.

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