Coverage Inputs
Example Data Table
| Scenario | Garden (m) | Tech | Obstacles | Fade Margin (dB) | Planned Range (m) | Recommended Nodes |
|---|---|---|---|---|---|---|
| Open beds | 20 × 12 | Sub‑GHz 915 | 1 | 10 | 38.4 | 1 |
| Hedges & trees | 30 × 18 | Wi‑Fi 2.4 | 4 | 15 | 11.2 | 6 |
| Shed and wall | 25 × 10 | Sub‑GHz 433 | 3 | 12 | 29.0 | 2 |
Numbers are illustrative so you can compare settings quickly.
Formula Used
This planner uses a log‑distance path loss model with a 1 meter reference:
Pr(dBm) = Pt + Gt + Gr − [FSPL(1m) + 10·n·log10(d)] − Lobs
Requirement: Pr ≥ Sensitivity + FadeMargin
Solve: d_max = 10^((Pt+Gt+Gr−Lobs−(Sensitivity+FadeMargin)−FSPL(1m)) / (10·n))
Then a conservative planning range is applied using the reliability factor, and a grid spacing is suggested to reduce dropouts near garden edges and around obstacles.
How to Use
- Enter garden length and width using your preferred units.
- Select the remote technology that matches your controller.
- Set sensitivity, fade margin, and antenna gains if known.
- Choose an environment preset, then fine‑tune the exponent.
- Add obstacles and losses for walls, sheds, and dense hedges.
- Click Calculate Coverage and review range and node counts.
- Download CSV or PDF to share the layout with installers.
Coverage planning in outdoor spaces
Smart remotes in gardens behave differently than indoor controls because foliage moisture, open-air reflections, and moving obstacles change signal strength. A coverage plan starts with realistic geometry, then adds margin so the remote keeps responding during irrigation, windy days, or seasonal growth. This calculator converts your garden dimensions into area and recommends spacing that reduces weak-edge zones and simplifies device placement for long beds, for multiple zones and controllers.
Link budget inputs that matter
Transmit power and antenna gain set the outgoing energy, while receiver sensitivity sets the minimum usable level. The planner combines these values with a fade margin to represent confidence under interference and fading. Obstacle losses capture walls, metal sheds, dense hedges, and wet leaves, which often dominate performance more than raw power alone. Use extra losses for cable runs, enclosures, and misalignment.
Range estimate and safety factor
Using a log-distance path loss model, the tool estimates a theoretical maximum distance and then applies a reliability factor for conservative design. The effective range is the distance you can plan around, not the farthest point you might briefly reach. If the effective range is small, consider sub‑GHz options, better antenna placement, fewer obstructions, or a higher sensitivity receiver. Increasing fade margin improves stability but reduces planned range.
Node count and placement strategy
The calculator proposes two independent node counts: a grid-based layout using recommended spacing and an area-based estimate using an effective circular coverage footprint. Blending both helps balance edge effects and overlap needs. Place a base controller centrally when possible, then distribute repeaters toward obstructed corners. Keep devices elevated and away from metal, motors, and power supplies. Maintain line-of-sight over paths where practical.
Field verification and iteration
After installation, validate coverage with a walk test and note any dropouts near corners, behind walls, or through thick shrubs. Lower the spacing factor to increase overlap, increase fade margin for harsher conditions, or add a repeater along the problematic path. Recheck performance after heavy rain and after pruning cycles, since vegetation density changes rapidly. Export the report to document assumptions, compare scenarios, and support maintenance decisions over time.
FAQs
1) What does the effective range represent?
It is a conservative planning distance after applying reliability. Use it for spacing and device count. Theoretical maximum range can be higher, but may be unstable with foliage, interference, or weather changes.
2) Which technology is best for large gardens?
Sub‑GHz links usually travel farther and handle foliage better. Wi‑Fi and BLE can work well for short ranges or where you can place repeaters, but they are more sensitive to congestion and attenuation.
3) How should I choose the fade margin?
Use 8–12 dB for open areas, and 12–18 dB for vegetation or mixed obstacles. Higher margin improves reliability, but reduces planned range and may increase the number of required nodes.
4) What counts as an obstacle in this planner?
Count major barriers along the path: brick walls, metal sheds, thick hedges, or dense tree lines. Use loss per obstacle to reflect severity, and add extra losses for enclosures, cables, and wet leaves.
5) Why are there two node estimates?
Grid estimation handles edge coverage and consistent spacing, while the area method approximates circular coverage footprints. Blending both provides a balanced recommendation for irregular signal behavior outdoors.
6) How do I verify the plan on site?
Do a walk test with the remote, log dropout locations, then adjust spacing factor or add a repeater near the failing segment. Retest after rain or seasonal growth because attenuation changes over time.