How to use 'idfrd' system object as a channel model in simulink

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

[Arkadiy Turevskiy]

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.

[Glo]

Thank you for your answer. That is exactly what I did. I used state-space modeling of the frequency domain data (in System Identification Toolbox), and exported the model as 'idss' object. Then used that object in LTI system block in Simulink.

I hope I am following the correct path. :)