MATLAB: Do I get a different bit error rate in R2018a for the AWGN channel block than in R2014a

Communications Toolbox

I have a communications model in R2014a that uses an AWGN Channel block in 'Signal to noise ratio (Eb/No)' mode and I am trying to update it to work in R2018a. My bit error rate is much higher in the R2018a model than in R2014a.
The only difference between the two models is that in R2014a, the AWGN Channel block uses the 'Inherited' option for the 'Input Processing' parameter and in R2018a this option does not exist.
How can I change my model to yield similar results to R2014a?

Best Answer

The Communication Systems Toolbox moved towards frame-based processing in R2015a so selecting the 'Inherited' option for the 'AWGN Channel' block began to generate an error, if selected, starting from this release onward.
Additional information on this can be found in the R2015a release notes:
https://www.mathworks.com/help/comm/release-notes.html#buoyaju
As of R2018a, the 'Inherited' option has been phased out entirely and this seems to be the source of the discrepancy between the two releases.
In the 18a model, if you divide the 'Symbol period (s)' of the AWGN Channel block by the length of the input signal to the channel, you should be able to observe the desired bit error rate from R2014a. This is because the R2018a model needs to be adjusted to use frame-based processing rather than sample-based processing.
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