Topic: Digital Communications
For a 10-bit ADC, the signal to quantization noise ratio (SNR) is 62 dB. If the bit resolution is increased by 2 bits, what would be the new SNR value?
- A. 62 dB
- B. 74 dB
- C. 50 dB
- D. 31 dB
Answer: B. 74 dB
Explanation: The signal-to-quantization-noise ratio (SQNR) of an ideal N-bit ADC is given by $SQNR \approx 6.02N + 1.76$ dB. This implies that each additional bit of resolution increases the SNR by approximately 6 dB. If the resolution is increased by 2 bits, the SNR increases by $2 \times 6 = 12$ dB. New SNR $= 62 + 12 = 74$ dB.