If for example you have a BER value of: 0.01358509373819659 and you want to calculate the revou (BER) simply calculates the logarithm of this value on the basis of 10 the result of negative: -1.866937 depending on the number of decimal places you adopted. Now you have the reverse revou (BER) = -1.866937 just use the logaratimo definition, 10 ^ ( -1.866937) = 0.0136, like used 4 homes decimal approximation value beats.
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