The dBm to dBmV conversion calculator converts power level values from dBm (decibels relative to 1 milliwatt) to dBmV (decibels relative to 1 millivolt). It is commonly used in RF, cable television, and communication systems to relate power measurements to voltage levels based on the system impedance.
Formula
dBmV = dBm + 30 + 20 * log10(√Z0)
Formula Explanation
- dBm represents the power level referenced to 1 milliwatt.
- Z0 is the system impedance in ohms, typically 50 or 75 ohm.
- The constant 30 converts milliwatts to microwatts on a logarithmic scale.
- The term 20 * log10(√Z0) converts power to voltage based on impedance.
- The result, dBmV, expresses the equivalent voltage level in decibels referenced to 1 millivolt.
Uses of this calculator
- Converting RF power readings to voltage levels in cable TV and broadband systems.
- Analyzing signal levels across systems with different impedance standards.
- Performing link budget calculations using voltage-based measurements.
- Educational purposes to understand relationships between power and voltage in decibel units.
What is 0 dBm in dBmV for a 75 ohm system?
Input: dBm = 0, Z0 = 75 ohm
Output:
- dBmV = 0 + 30 + 20 * log10(√75) = 30 + 20 * log10(8.66) = 30 + 20 * 0.937 = 30 + 18.74 = 48.74 dBmV
- 0 dBm = 48.74 dBmV