MATLAB: Undefined variable “comm” or class “comm.Rais​edCosineTr​ansmitFilt​er”.

Question

Hi, I am just trying the codes to design a raised cosine filter. There are already codes found in the web http://www.mathworks.com/help/comm/examples/raised-cosine-filtering.html. And what I did what just copy and paste the codes there onto my command window to try out. Below are the codes:

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Nsym = 6;           % Filter span in symbol durations
beta = 0.5;         % Roll-off factor
sampsPerSym = 8;    % Upsampling factor
rcosFlt = comm.RaisedCosineTransmitFilter(...
  'Shape',                  'Normal', ...
  'RolloffFactor',          beta, ...
  'FilterSpanInSymbols',    Nsym, ...
  'OutputSamplesPerSymbol', sampsPerSym)
% Visualize the impulse response
fvtool(rcosFlt, 'Analysis', 'impulse')
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

I expect it to work, however I am given an error "Undefined variable "comm" or class "comm.RaisedCosineTransmitFilter"."

I have the Signal Processing Toolbox, and even when I tried the above codes in my school computer it also throws out the same error.

As such, I tried to design the raised cosine filter using the function rcosdesign(), again I copied the codes from the example and simply paste it in the command window. Again it throws out the error undefined function 'rcosdesign' for input arguments type double. =(

Can someone help me please.

Thanks.

Answer 1

You need Communications System Toolbox license to use comm.RaisedCosineTransmitFilter. You can use

>> ver

to see if you have that toolbox installed.

HTH