how to use 'pskmod'

Am getting the following errors while I run the below code.

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??? Error using ==> mtimes Complex integer arithmetic is not supported.

Error in ==> pskmod at 101 y = exp(j*(theta + ini_phase));

Error in ==> lena at 9 txpsk = pskmod(msg,M);

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M = 2; %Modulation order 2 for BPSK

imdata = imread('http://openvip.sourceforge.net/userdoc/lena_grayscale.jpg'); bdata = de2bi(imdata);

sizec = size(bdata,1);

sizer = size(bdata,2);

nbits = sizec*sizer;

msg = reshape(bdata,nbits,1);

txpsk = pskmod(msg,M);

Answer 1

[Greg Dionne]

You'll want to convert from integer to double precision first.

txpsk = pskmod(double(msg),M);