Calculator Inputs
Example Data Table
These example rows are illustrative planning cases for comparing typical design assumptions.
| Scenario | Frequency | Tx Power | Tx Gain | Rx Gain | Environment | Fade Margin | Beamwidth |
|---|---|---|---|---|---|---|---|
| Campus Wi-Fi sector | 2400 MHz | 5 W | 15 dBi | 2 dBi | Suburban | 15 dB | 120° |
| Rural telemetry link | 900 MHz | 2 W | 12 dBi | 5 dBi | Rural / Open | 12 dB | 60° |
| Dense city backhaul | 5800 MHz | 8 W | 23 dBi | 18 dBi | Dense Urban | 20 dB | 30° |
Formula Used
1) Transmit power conversion:
Transmit Power (dBm) = 10 × log10(Power in watts × 1000)
2) Effective isotropic radiated power:
EIRP (dBm) = Tx Power (dBm) + Tx Gain − Tx Feeder Loss − Miscellaneous Loss
3) Maximum allowable path loss:
MAPL (dB) = Tx Power + Tx Gain + Rx Gain − Tx Loss − Rx Loss − Misc Loss − Fade Margin − Rx Sensitivity
4) Free-space path loss at 1 meter:
FSPL1m (dB) = 32.44 + 20 × log10(Frequency in MHz) − 60
5) Log-distance propagation model:
Path Loss (dB) = FSPL1m + 10 × n × log10(distance in meters) + clutter loss
6) Link-limited distance:
Distance (m) = 10(MAPL − FSPL1m − clutter loss) / (10 × n)
7) Radio horizon estimate:
Horizon (km) = 3.57 × √k × (√Tx Height + √Rx Height)
8) Sector area:
Sector Area = π × radius² × (horizontal beamwidth / 360)
How to Use This Calculator
- Enter operating frequency, transmitter power, and both antenna gains.
- Add feeder losses, miscellaneous system loss, and the required fade margin.
- Provide receiver sensitivity and both antenna heights.
- Set horizontal beamwidth for the sector and vertical beamwidth for footprint estimation.
- Select an environment model matching the deployment area.
- Adjust extra clutter loss when foliage, buildings, or heavy blockage exist.
- Press Calculate Coverage to show the result directly below the header.
- Download the calculated result as CSV or PDF when needed.
Frequently Asked Questions
1. What does antenna coverage mean here?
It is the estimated service radius where received signal stays above the required threshold after gains, losses, fade margin, terrain model, and horizon limits are applied.
2. Why does higher frequency often reduce range?
Higher frequencies usually suffer greater free-space loss and obstruction loss. With the same power and gain, they often produce shorter practical reach.
3. Why is fade margin important?
Fade margin keeps reserve signal headroom against rain, foliage, multipath, and loading changes. More margin improves reliability but usually reduces predicted radius.
4. What is the difference between link-limited and horizon-limited?
Link-limited range ends when available path loss is exhausted. Horizon-limited range ends when antenna height and Earth curvature restrict useful line of sight.
5. How does beamwidth change the result?
Horizontal beamwidth changes covered sector area. Vertical beamwidth works with downtilt to estimate near and far ground footprint distances.
6. Are these results exact field values?
No. They are engineering estimates. Interference, Fresnel clearance, device orientation, reflections, local blockage, regulations, and equipment quality can change real performance.
7. Why is receiver sensitivity included?
Receiver sensitivity defines the weakest acceptable receive level. Better sensitivity increases allowable path loss and usually extends estimated coverage distance.
8. When should I validate with field testing?
Always validate professional deployments, long links, dense urban sites, and safety-critical systems. Field testing confirms assumptions and reveals interference or blockage.