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Friis Transmission Equation, Free-Space Path Loss (FSPL) & Received Power Calculator

Easily calculate and compute friis transmission equation, free-space path loss (fspl) & received power calculator with accurate equations, live formulas, and expert guidance.

RF power entering transmit antenna.

Transmitter antenna directional gain.

Receiver antenna directional gain.

Signal frequency in Gigahertz (e.g. 12 GHz for Ku-band).

Separation distance (e.g. 35,786 km for GEO satellite).

Calculated Result
-129.1 dBm

Received Power (P_r)

Received Power (P_r)

-129.1 dBm

Received Power Pr Dbm

-129.1

Free Space Path Loss Db

205.1

Equivalent Isotropic Radiated Power Eirp Dbm

54

Received Power Picowatts

0

-129.1 — dBm

Calculation Breakdown

  1. Applied FormulaSolves the fundamental Friis transmission equation, computing free-space spherical wave spreading attenuation (FSPL) and received RF power for satellite and line-of-sight links.\frac{P_r}{P_t} = G_t G_r \left(\frac{\lambda}{4\pi d}\right)^2, \quad \text{FSPL}_{dB} = 32.44 + 20\log_{10} d_{km} + 20\log_{10} f_{MHz}

Friis FSPL & Link Budget Metric Output

Interactive visualization based on your current inputs

Calculated Value
-129.1-96.6-64.0-31.51.0Received Power (P_r)

What Is the Friis Transmission Equation, Free-Space Path Loss (FSPL) & Received Power Calculator?

This tool computes friis transmission equation, free-space path loss (fspl) & received power calculator with high precision arithmetic.

How Does the Friis Transmission Equation, Free-Space Path Loss (FSPL) & Received Power Calculator Work?

Solves the fundamental Friis transmission equation, computing free-space spherical wave spreading attenuation (FSPL) and received RF power for satellite and line-of-sight links.

Friis Transmission Equation, Free-Space Path Loss (FSPL) & Received Power Calculator Formula & Variables

The core mathematical equation utilized by this calculator is expressed as:

PrPt=GtGr(λ4πd)2,FSPLdB=32.44+20log⁡10dkm+20log⁡10fMHz\frac{P_r}{P_t} = G_t G_r \left(\frac{\lambda}{4\pi d}\right)^2, \quad \text{FSPL}_{dB} = 32.44 + 20\log_{10} d_{km} + 20\log_{10} f_{MHz}

Solves the fundamental Friis transmission equation, computing free-space spherical wave spreading attenuation (FSPL) and received RF power for satellite and line-of-sight links.

How to Use the Friis Transmission Equation, Free-Space Path Loss (FSPL) & Received Power Calculator

  1. Enter your parameters into the designated input fields to calculate the result immediately.

Step-by-Step Example Calculation

Friis Transmission Equation, Free-Space Path Loss (FSPL) & Received Power Calculator Example

Input Values:

transmitPowerWatts:10
transmitAntennaGainDbi:14
receiveAntennaGainDbi:22
carrierFrequencyGhz:12
linkDistanceKm:35786
Worked Steps: Sample evaluation based on standard reference conditions.

Understanding Your Result

The calculated primary figure indicates the optimal or required dBm.

Factors That Affect the Result

  • Measurement tolerances, operational variance, and real-world conditions.

When Should You Use This Calculator?

  • Everyday budgeting, technical homework, professional estimation, and household projects.

Assumptions & Limitations

  • Assumes standard atmospheric or environmental parameters unless specified.

Frequently Asked Questions

Calculation Accuracy & Reference Note

Double-precision IEEE 754 arithmetic with validated empirical constants.

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