This tool helps convert from μV (microvolt) to dBµV (deciBel microvolt).
Note that μV is a positive number that represents the root-mean-square (RMS) voltage and it cannot be less than zero.
Formula
dBµV = 20*Log10(µV)
The same formula applies when converting either quantity scaled by distance (e.g. per-meter)
dBµV/m = 20*Log10(µV/m)
Background
The dB scale is a very convenient representation for large numbers and allows for easy multiplication of two linear quantities.
uV/m or microvolt-per-meter is used by the FCC to specify radiated limits for RF equipment at a 3-meter distance from the source.
The first three columns of the following table of Radiated Emissions Limit is from [1]. The calculator is used to find the dBuV/m equivalent value
Freq. (MHz) | uV/m | dBuV/m | Distance (m) |
---|---|---|---|
30-88 | 100 | 40 | 3 |
88-216 | 150 | 43.5 | 3 |
216-960 | 200 | 46 | 3 |
Above 960 | 500 | 54 | 3 |
Related Calculators
Use this calculator to find the max transmit power (in dBm) for an equivalent dBuV/m power. This is a way to quickly calculate whether your transmitter is within the FCC specified emissions limit.