Received Power Calculator For Windows

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 is a fundamental formula in telecommunication engineering that calculates the power received by an antenna from another antenna some distance away, given the transmit power, antenna gains, wavelength, and distance.

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, converted to linear scale)
\( G_r \) — Receive antenna gain (dB, converted to linear scale)
\( \lambda \) — Wavelength (m)
\( d \) — Distance between antennas (m)

Explanation: The equation accounts for free-space path loss and antenna characteristics to determine the received power level.

3. Importance of Received Power Calculation

Details: Accurate received power calculation is crucial for wireless communication system design, link budget analysis, and determining signal strength at the receiver.

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 positive.

5. Frequently Asked Questions (FAQ)

Q1: What is the significance of the wavelength parameter?
A: Wavelength determines the frequency of operation and affects how signals propagate through space and interact with antennas.

Q2: Why convert dB gains to linear scale?
A: The Friis equation requires gains in linear form, while antenna specifications are typically given in dB for convenience.

Q3: What are typical values for antenna gains?
A: Isotropic antennas have 0 dB gain, while directional antennas can have gains from 3-30 dB depending on design and application.

Q4: What are the limitations of the Friis equation?
A: The equation assumes free-space propagation, perfect antenna alignment, polarization matching, and no obstructions or reflections.

Q5: How does distance affect received power?
A: Received power decreases with the square of the distance due to the spreading of electromagnetic waves in free space.