Question

A $8kHz$ communication channel has an $SNR$ of $30dB$. If the channel bandwidth is doubled, keeping the signal power constant, the $SNR$ for the modified channel will be

• A. $27dB$
• B. $30dB$
• C. $33dB$
• D. $60dB$.

Answer 1

The correct option is B $30dB$

Signal- noise ratio is given by

$SNR=10\log \left(\frac{\text{power of signal}}{\text{Noise power}}\right)$

By changing bandwidth, SNR remains unaffected i.e $30dB$

Hence option B is correct.