What are system gain and attenuation typically expressed as?

System gain and attenuation are typically expressed in decibels (dB) because this logarithmic scale allows for more manageable comparisons and calculations in signal processing and telecommunications. The use of decibels simplifies the expression of ratios, which is particularly useful when dealing with large variations in signal strength, such as in audio and radio frequency applications.

For example, if a signal strength increases or decreases, expressing that change in dB shows the relative change in power level in a concise manner. A value of 3 dB corresponds to a doubling of power (gain) or halving of power (attenuation), making the dB scale extremely effective in conveying these changes intuitively.

The other options do not offer the same clarity or efficiency in communication. Voltage and wattage can also describe gain or loss, but they do not encompass the broad range of applications and interpretations that decibels provide. Frequency does not directly relate to gain or loss, as gain and attenuation are more about power levels rather than variations in signal frequency.