Registered Communications Distribution Designer (RCDD-001) — Question 4

If the input signal power to a communication system is 1 W and the output power is 1 mW, the system attenuation is:

Answer options

• A. 3 dB
• B. 20 dB
• C. 30 dB
• D. 40 dB
• E. 1000 dB

Correct answer: C

Explanation

The attenuation can be calculated using the formula: Attenuation (dB) = 10 * log10(Pin/Pout). Here, Pin is 1 W and Pout is 1 mW, resulting in 10 * log10(1000) which equals 30 dB. The other options do not represent the correct calculation of attenuation based on the given power levels.