Question
Download Solution PDFWhich one of the following digital modulation schemes has the bit error rate as \(\dfrac{1}{2}\rm{erfc} \left( \sqrt{\dfrac{E_b}{N_0}} \right)\) ?
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFoption 1 is correct
BPSK
S1(t)= Ac cos (2πfc t)
S2(t)= -Ac cos (2πfc t)
Bit error rate (BER) for BPSK given as
\((BER)_{BPSK}= Q\sqrt \frac{A_C^2\times T_b}{N_o }\)
noise power =No/2
bit energy(Eb)=Ac2Tb/2
\((BER)_{BPSK}= Q\sqrt \frac{2\times E_b}{N_o }\)
Relation between Q(x) and erfc are
Q(x)=1/2 erfc (x/√ 2)
\((BER)_{BPSK}=Q\sqrt { (2E_b/N_o)}=1/2× erfc(\sqrt {(E_b/N_o)}\)
Last updated on Jul 2, 2025
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