Editing FM Homework Assignment Questions (section)

===Question 21===
Our situation was that after incorporating the noise increase factor  of 1.1530 into the theoretical SNR, our simulated SNR for the sine wave was exceeding the theoretical value by a small amount (0.15~0.3dB) after a certain threshold point (around 11.5dB of pre-detection SNR). The random signal's simulated SNR, 
however, did not show this behaviour and remained below the theoretical value at all times as expected.

After a great number of simulations and checking intermediate working steps, we concluded that there could be two reasons for this effect:

:1. The noise increase factor of 1.1530 is only approximate and causes the theoretical SNR to drop a bit further than it actually should.

:2. Approximation of integrals by summations in modulating and demodulating cause the final result to change slightly.

I personally think it's the first reason that is throwing our results off. If you don't mind us asking, how is the noise increase factor
of 1.1530 calculated for a 5th order Butterworth filter and under what  conditions is this accurate?

'''Answer 21:''' The increased noise output of 1.1530 times larger than with an ideal filter is associated with the practical implementation of the digital filter, not the waveform. To state a factor to five figures could hardly be regarded as approximate. If you started with the same code for each case and have edited to apply to each case, one possibility is you have missed some edits. Worth you checking the code.