MATLAB: How to use ‘idfrd’ system object as a channel model in simulink

Question

Hello dear members,

I have created an idfrd object using measured frequency response data (using Magnitude/Angle measurements). Now I want to incorporate this data into a continuous time SISO model, which I can place as the channel between Tx/Rx in a communication system simulation.

I have tried using 'LTI system' block from Control System Toolbox library, but it does not support idfrd system object.

What can I do now? Is there any alternative way to address this issue? I am using Matlab/Simulink 2014a.

Thanks!

Answer 1

You cannot do time domain simulation on a frequency response model. What you can do is fir a transfer function or state space model to match the measured frequency response. You can use commands tfest and ssest for that. Once you have a transfer function/state-space object, you'll be able to simulate in Simulink using LTI system block or just Transfer Function and State Space blocks.