Hi Ravil,
Actually I have explained in my second comment that adding the magnitude to the signal exiting the coherent detection block does not move the symbols, because it is added to a signal that has not been processed and therefore does not represent the symbols yet (although it contains the information that the symbols are supposed to be extracted from, after exiting the coherent detection block and then passing through the demodulation block(which is in my case an OFDM demodulation block)). I was clearly wrong about it in my first post.