Calculator Inputs
Example Data Table
| Scenario | Model | Frequency | Distance | Extra Losses | Expected Use |
|---|---|---|---|---|---|
| Point-to-point rooftop backhaul | Free-Space | 5800 MHz | 3.2 km | Feeder, connectors, fade margin | Clear LOS microwave links |
| Warehouse wireless bridge | Log-Distance | 2400 MHz | 0.18 km | Walls, clutter, shadow fading | Indoor or semi-obstructed paths |
| Urban macrocell planning | Hata Urban | 900 MHz | 4.5 km | Misc, polarization, fade reserve | Dense city deployment checks |
| Suburban LTE sector | Hata Suburban | 850 MHz | 7.0 km | Connector, line, weather losses | Outer-city cellular analysis |
| PCS network planning | COST-231 Hata | 1800 MHz | 2.8 km | Rain, feeder, foliage, margin | Higher-band terrestrial studies |
Formula Used
1) Free-Space Path Loss
FSPL = 32.44 + 20log10(f_MHz) + 20log10(d_km)
2) Log-Distance Model
PL(d) = PL(d0) + 10nlog10(d/d0) + Xσ
Here, n is the path loss exponent and Xσ represents added shadow fading.
3) Okumura-Hata Urban
Lurban = 69.55 + 26.16log10(f) - 13.82log10(hb) - a(hm) + (44.9 - 6.55log10(hb))log10(d)
4) Okumura-Hata Suburban
Lsuburban = Lurban - 2[log10(f/28)]² - 5.4
5) Okumura-Hata Open Area
Lopen = Lurban - 4.78[log10(f)]² + 18.33log10(f) - 40.94
6) COST-231 Hata
LCOST231 = 46.3 + 33.9log10(f) - 13.82log10(hb) - a(hm) + (44.9 - 6.55log10(hb))log10(d) + Cm
Total received power is found by adding transmit power and antenna gains, then subtracting modeled path loss and all entered practical losses.
How to Use This Calculator
- Select the propagation model that matches your environment and frequency range.
- Enter frequency, link distance, transmit power, and both antenna gains.
- Add feeder, connector, wall, foliage, weather, and miscellaneous losses.
- Enter receiver sensitivity and the fade margin you want to protect.
- For log-distance or Hata-based models, fill in the model-specific fields.
- Press Calculate Propagation Loss to view the result above the form.
- Use the CSV export for reporting and the PDF export for sharing summaries.
- Review the graph to see how received power changes over distance.
FAQs
1) What does propagation loss mean?
Propagation loss is the signal reduction that happens as radio energy travels through space and obstacles. It directly affects received power and final link reliability.
2) When should I use the free-space model?
Use free-space when the path is clear, line-of-sight dominates, and reflections or clutter are minimal. It is common for basic microwave and backhaul estimates.
3) Why does the log-distance model need an exponent?
The exponent describes how quickly loss grows in a specific environment. Open areas may be near 2, while cluttered indoor or urban paths can be much higher.
4) What is the difference between link margin and design margin?
Link margin compares received power against receiver sensitivity. Design margin goes further by subtracting your required fade reserve, giving a more conservative readiness measure.
5) Why include rain, wall, or foliage losses?
These losses capture real deployment conditions. Ignoring them can make a link look stronger on paper than it will behave in practical field operation.
6) Are Hata and COST-231 models valid everywhere?
No. They are empirical models with frequency, height, and distance ranges. Results are best when the entered scenario stays near their intended planning limits.
7) Why is received power shown in negative dBm?
Wireless receivers often work with very small power levels. Negative dBm values are normal and still usable when they remain above sensitivity with enough margin.
8) Can I use this for Wi-Fi, microwave, and cellular links?
Yes. The calculator supports several common planning styles. Choose the model that best matches your frequency band, terrain, antenna heights, and obstruction profile.