Received Power Calculator For Electricity

Friis Transmission Equation:

\[ P_r = P_t \times G_t \times G_r \times \left(\frac{\lambda}{4 \pi d}\right)^2 \]

Transmitted Power (P_t):

Transmit Gain (G_t):

Receive Gain (G_r):

Wavelength (λ):

Distance (d):

Received Power (P_r):

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1. What Is The Friis Transmission Equation?

The Friis transmission equation calculates the power received by an antenna from a transmitter in free space. It's a fundamental equation in wireless communications that describes how much power is received given various transmission parameters.

2. How Does The Calculator Work?

The calculator uses the Friis transmission equation:

\[ P_r = P_t \times G_t \times G_r \times \left(\frac{\lambda}{4 \pi d}\right)^2 \]

Where:

\( P_t \) — Transmitted power (W)
\( G_t \) — Transmit antenna gain (dB)
\( G_r \) — Receive antenna gain (dB)
\( \lambda \) — Wavelength (m)
\( d \) — Distance between antennas (m)

Explanation: The equation accounts for free-space path loss and the gains of both transmitting and receiving antennas to determine the received power level.

3. Importance Of Received Power Calculation

Details: Accurate received power calculation is crucial for wireless system design, link budget analysis, signal strength prediction, and ensuring reliable communication in various applications including radio, satellite, and cellular systems.

4. Using The Calculator

Tips: Enter transmitted power in watts, antenna gains in dB, wavelength in meters, and distance in meters. All values must be valid positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What Is Free-Space Path Loss?
A: Free-space path loss is the attenuation of radio energy between the transmitter and receiver due to the spreading of the wavefront in free space, represented by the (λ/4πd)² term.

Q2: How Do I Convert Between dB And Linear Gain Values?
A: Linear gain = 10^(dB/10). The calculator automatically converts dB gains to linear values for the calculation.

Q3: What Are Typical Values For Antenna Gains?
A: Typical values range from 0-3 dB for simple antennas, 6-15 dB for directional antennas, and up to 30+ dB for high-gain parabolic antennas.

Q4: Does This Equation Account For Real-World Conditions?
A: The basic Friis equation assumes ideal free-space conditions without obstacles, reflections, or atmospheric effects. Real-world calculations may require additional factors.

Q5: How Does Wavelength Relate To Frequency?
A: Wavelength (λ) = speed of light (c) / frequency (f). For radio waves, λ = 300 / f (MHz) in meters.