How to Calculate RF Power

RF Power Formula:

\[ P = \frac{V^2}{R} \]

Power (P): watts

Definition: This calculator determines the power in an RF circuit using the voltage and resistance values.

Purpose: It helps radio frequency engineers, technicians, and hobbyists calculate power dissipation in RF systems.

The calculator uses the formula:

\[ P = \frac{V^2}{R} \]

Where:

Explanation: The voltage is squared and then divided by the resistance to calculate the power in watts.

Details: Accurate power calculation ensures proper system design, prevents component damage, and helps meet regulatory requirements.

Tips: Enter the voltage in volts and resistance in ohms (default 50Ω for most RF systems). All values must be > 0.

Q1: Why is 50 ohms the default resistance?
A: 50 ohms is the standard characteristic impedance for most RF systems and coaxial cables.

Q2: Is this formula valid for AC signals?
A: Yes, but use RMS voltage values for AC signals to get accurate power calculations.

Q3: How does this relate to dBm measurements?
A: You can convert watts to dBm using: dBm = 10 × log10(P/0.001).

Q4: What if I know current instead of voltage?
A: Use P = I² × R where I is current. We may add this option in future versions.

Q5: Does this account for system losses?
A: No, this calculates theoretical power. Actual power may be lower due to system losses.