In digital modulation, a positive voltage represents a 1 and a negative voltage represents a 0. For an optical fibre, the presence and absence of light is represented by 1 and 0 respectively. This scheme is known as __________.
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non-return-to-zero
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return-to-zero
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non-to-zero
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one-to-zero
A
Correct answer
Explanation
In digital modulation, a positive voltage represents a 1 and a negative voltage represents a 0. For an optical fibre, the presence and absence of light is represented by 1 and 0 respectively. This scheme is known as non-return-to-zero. This typical name is given for historical reason.