Question

The power SNR of an imaging system is 4 dB. The dominating noise in this system is white noise with average power of 4 mW. Calculate the average power of the signal.

Answer 1

10.0 mW

Step-by-step explanation:

By definition, the SNR of any system is expressed as follows:

`SNR (dB) = 10 log ((S)/(N))`

where

S = average power of the signal

N= average noise power

In this case this relationship can be written as follows, repalcing by the givens:

`SNR (dB) = 10 log ((S)/(4mW)) = 4 dB`

Rearranging terms, and taking log₁₀ on both sides, we have:

`10* log (S)/(N) = 4 dB \\ log (S)/(N) = 0.4 \\\ (S)/(N) = 10^(0.4) \\ S= 4e-3 W* 10^(0.4) = 10.0 mW`

⇒ Pavg = 10 mW