Decibels
Decibels are used to specify ratios of powers and voltages in a logarithmic fashion. Absolute levels can also be specified by supplying suitable reference values. Decibels are commonly used for gain and loss calculations in electronic systems. Generally, spectrum and network analyzers display measurement results with their displays calibrated in decibels. The popularity of the decibel in such applications is due to its ability to compress logarithmically widely varying signal levels. For example, a 1 V signal and a 0.1 mV signal can both be represented on a display with 100 dB of range. To show these two signals simultaneously with reasonable clarity on a linear scale is impractical. Decibels also are useful for gain and loss calculations, where multiplication operations are transformed into (easier) additions.
Decibels, Page 1 of 2
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