Undefined function 'awgn' for input arguments of type 'double'.

I am using simulink 2012a version and when I cut and paste the code from the help utility, t = 0:.1:10; x = sawtooth(t); % Create sawtooth signal. y = awgn(x,10,'measured'); % Add white Gaussian noise.

I get the above error. I changed "x" to a matrix of zeros(1,10000) and I still get the same error message so it is not the data type of input. Do I need to load a particular library?

Thanks for your help

[TAB]

Are you using above code in Embedded Matlab function block ?

[Mark]

No I am simply entering it in the "command window".

[TAB]

"I am using simulink 2012a version" -- what it means ?

Do you mean Matlab 2012 version ?

[Mark]

Yes Matlab. Sorry, I looked at the wrong window.

[Avinas Vem]

I have a similar problem.Weird thing is I had my awgn function working yesterday.But today on the same system it doesn't work.And yes I have my communication systems toolbox installed.(ver tells me that i have that toolbox)

snr=3; x=ones(10,1)'; y=awgn(x,snr); Undefined function 'awgn' for input arguments of type 'double' " is the message displayed.

Should i unlock the Comm Systems toolbox or something?

Answer 1

[Wayne King]

You need the Communications System Toolbox. Do you have that installed?

Enter

>>ver

to see if you have an entry like:

Communications System Toolbox Version (R2012a)

[Mark]

Thanks for the info. When I do a ver, communication system toolbox is not listed.

[Wayne King]

There is your answer. If you want to add white Gaussian noise, you can use randn()

[Noor Khan]

I have the same problem. Moreover, the randn function is not working as well. what can I do now? help required please. Thanks.