Calculator Inputs
Example Data Table
| Scenario | Frequency | Tx Power | Walls / Floors | Environment | Typical Planning Use |
|---|---|---|---|---|---|
| Small Home Router | 2400 MHz | 18 dBm | 2 walls / 0 floors | Residential | General indoor browsing coverage |
| Office Access Point | 5000 MHz | 20 dBm | 3 walls / 0 floors | Light Office | Faster office throughput planning |
| Warehouse Link | 5800 MHz | 23 dBm | 0 walls / 0 floors | Warehouse | Open-area directional deployment review |
| Multi-Floor Building | 2400 MHz | 20 dBm | 2 walls / 1 floor | Dense Office | Vertical penetration estimation |
Formula Used
1) Transmit EIRP:
EIRP (dBm) = Transmit Power - Transmit Cable Loss + Transmit Antenna Gain
2) Available Outdoor Link Budget:
Link Budget (dB) = EIRP + Receive Antenna Gain - Receive Cable Loss - Receiver Sensitivity - Fade Margin - Miscellaneous Loss
3) Free-Space Path Loss:
FSPL (dB) = 32.44 + 20 log10(Frequency MHz) + 20 log10(Distance km)
4) Outdoor Range:
Distance (km) = 10 ^ ((Link Budget - 32.44 - 20 log10(Frequency MHz)) / 20)
5) Indoor Path Loss Model:
PL(d) = PL(1m) + 10n log10(d) + Wall Loss + Floor Loss
6) Indoor Range:
d = 10 ^ ((Indoor Budget - PL(1m)) / (10n))
These values are planning estimates. Real WiFi performance also changes with interference, channel width, reflections, client radios, and antenna direction.
How to Use This Calculator
- Enter your operating frequency in MHz.
- Provide transmitter power, antenna gains, and cable losses.
- Add receiver sensitivity from your radio or client specification.
- Choose a fade margin for reliability.
- Enter extra losses from walls, floors, and other obstacles.
- Select an environment profile or supply a custom path-loss exponent.
- Add a test distance to inspect estimated RSSI at a target point.
- Submit the form and review the range, RSSI, budget, and chart.
- Export the summary as CSV or PDF for reports.
FAQs
1) What does this calculator estimate?
It estimates WiFi range using link budget, free-space loss, indoor attenuation, and a log-distance model. It helps compare theoretical outdoor reach and more practical indoor coverage.
2) Why does higher frequency often reduce range?
Higher frequencies usually experience more path loss over the same distance. That often reduces coverage unless antenna gain, transmit power, or receiver performance compensates for it.
3) Why are indoor and outdoor results different?
Outdoor calculations assume open free-space conditions. Indoor estimates add wall, floor, and environment losses, which lower signal strength and shorten coverage distance.
4) What is receiver sensitivity?
Receiver sensitivity is the weakest signal your device can decode at a chosen data rate. Better sensitivity lets a link remain usable at lower received power levels.
5) Why should I include fade margin?
Fade margin protects the design from signal swings caused by interference, movement, weather, reflections, or device differences. More margin usually means better reliability.
6) What is the path-loss exponent?
It describes how quickly signal weakens in a specific environment. Open spaces have lower values, while dense offices and concrete buildings usually have higher values.
7) Can this replace a site survey?
No. It is a planning tool, not a measurement tool. Real deployments should still be validated with a site survey, heatmap, or field testing.
8) Which inputs matter most first?
Start with frequency, receiver sensitivity, fade margin, obstacle losses, and realistic antenna gain. Those usually affect the estimate more than small cable adjustments.