ERFC curves

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ERFC curves

• Torino, 12/6/2001

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Description

• The following slides show erfc() curves
• In particular, the following graph is shown
• where the ordinate x is shown on the graph in dB
• In the last slide, a useful approximation is given

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Graph for higher BER
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Graph for lower BER
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Matlab program for generating the curves
clear x_dB1.59 x_linear10.(x_dB/10)
BER0.5erfc(sqrt(x_linear)) figure(1) semilogy
(x_dB,BER) grid on zoom on set(gca,'Fontsize',1
8)
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Analytical approximation

• The following useful approximation is suitable
  whenever the results is smaller than 10-2