Signal Propagation Simulator

Explore how distance, frequency, obstacles, and receiver sensitivity shape an IoT radio link

A guided wireless signal propagation simulator with path-loss models, obstacle attenuation, link-budget diagnosis, and synchronized desktop/mobile visuals.

Animation Wireless Propagation

Signal Propagation Simulator

Move distance, frequency, obstacles, antennas, and receiver sensitivity. Watch the wavefront, shadow loss, received power, and link margin update as one connected propagation story.

96.2 dBTotal path loss

-78.2 dBmReceived power

6.8 dBFade-adjusted margin

Usable linkLink status

Goal

See how a radio wave weakens before it reaches an IoT receiver.

Try First

Double distance, then switch frequency. Compare what changes in path loss and wall loss.

Watch

The active stage, wavefront, obstacle shadow, numeric budget, and diagnosis stay synchronized.

Why It Matters

Coverage problems often come from using free-space intuition in cluttered rooms or metal-heavy sites.

Scenario

Choose a starting deployment.

Model

Choose the propagation teaching model.

Playback

Play speed 900 ms

Radio Path

Distance 35 m

Frequency 2.40 GHz

Path exponent 3.0

Obstacles 2

Material

Choose the obstacle type used by the teaching approximation.

Link Budget

TX power 14 dBm

TX antenna 2 dBi

RX antenna 2 dBi

Sensitivity -95 dBm

Fade margin 10 dB

Emit: the transmitter starts with EIRP, then the wave spreads through space.

RX above -85.0 dBm.Expected behavior

35 m at 2.40 GHz.Observed path

Usable but not generous.Working diagnosis

Propagation Field

Wave rings expand from TX. Obstacles add loss and create a teaching shadow before the receiver.

Stage 1 of 5 Emit -> EIRP

Calculation Detail

The selected model estimates received power for the current path.

Model Fitness

Checks whether the selected teaching model matches the selected environment.

good fit

Coverage Radius

Approximate distance where fade-adjusted margin reaches zero.

59 m

Obstacle Pressure

Shows how much material loss is consuming the link budget.

9.8 dB

Beginner Ramp

A radio signal spreads as it travels. Distance reduces received power even in clear air. Buildings, shelves, people, and antenna orientation add extra loss.

Formula Reference

• FSPL dB = 32.44 + 20log10(distance km) + 20log10(frequency MHz).
• Log-distance dB = FSPL at 1 m + 10nlog10(distance / 1 m).
• Received dBm = TX power + TX gain + RX gain - total path loss.

Frequency Effect

Higher frequency usually has more free-space loss at the same distance and often penetrates materials less well. Exact material loss depends on construction and measurements.

Model Limits

Free-space is a lower-bound baseline. Log-distance needs a measured exponent. The material-loss approximation here is for intuition, not a site-survey replacement.

Fade Margin

Fade margin reserves budget for people moving, doors opening, humidity, multipath fading, antenna rotation, and hardware variation.

Deployment Clue

If margin is thin, try lower frequency, shorter distance, fewer obstacles, better antenna placement, or a more sensitive receiver before only increasing power.

Practice 1

Use Office Walls. Switch from 2.4 GHz to 868 MHz without changing distance. Which parts of the budget improve?

Practice 2

Use Warehouse Shelves and select Metal Rack. How much margin do you lose as obstacles increase?

Practice 3

Select Free Space while keeping obstacles. What warning appears, and why is free-space too optimistic?

Related Study

RF Path Loss CalculatorInspect model formulas and link margin in more detail. Fresnel and MultipathSee clearance and reflection effects. Link Budget and AntennasConnect received power to antenna patterns. Wireless Range CalculatorPlan range for common IoT link types.