title: AWGN BER simulation on MATLAB/Simulink does not generate the same theoretical results
body: <p>The Simulink simulation is shown below: </p>
  
  <p><a href="https://i.stack.imgur.com/VABop.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/VABop.png" alt="enter image description here"></a></p>
  
  <p>I am attempting a simulation of a very simple system using BPSK at a rate of 10 MHz. However, I am not sure about the AWGN block values. Specifically,  </p>
  
  <ol>
  <li><p>On "Signal to Noise Ratio (Eb/No)", what is the "Input signal power, referenced to 1 ohm (watts)" parameter?. How can I calculate this value? When I use the default value, which is 1, I get the following curve:
  <a href="https://i.stack.imgur.com/zToO2.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/zToO2.png" alt="enter image description here"></a></p></li>
  <li><p>Alternatively, when I am simulating using the "Variance from Mask" option and variance = 10^(-EbNo/10), I get the following result:</p></li>
  </ol>
  
  <p><a href="https://i.stack.imgur.com/ePJGg.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/ePJGg.png" alt="enter image description here"></a></p>
  
  <p>Clearly, they theoretical and simulated curves are not overlapping. For this plot, I am using the Monte Carlo option found in BERTool.</p>