Coverage Predictions

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Revision as of 09:29, 17 June 2026 by Trm (talk | contribs) (prop models (not finished))
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Calculate Coverage

Coverage calculations are controlled by the interface IRadioCoverage in IMariaRadioPlanLayer.RadioCoverage

To create a coverage file, we need to define some parameters. The most important is the selection of propagation model.

The list of propagation models can be found like this:

_propagationModels = new ReadOnlyCollection<string>(_radioPlanLayer.RadioCoverage.RadioPropagationModelRepository.PropagationModels.Select(m => m.Name).ToList());

Settings for Coverage calculation used is defined by

record CoverageCalculationSettings(int resolution, int size, AreaShape calculationAreaShape, string propagationModel, RxHeight rxHeight, PartsOfCalculation partsToCalculate)

which is set RadioNet setting:

  • RadioNet.CoverageCalculationSettings

or as a general setting:

  • RadioPlanSettings.CoverageCalculationSettings

Which one to use is controlled by enum RadioPlanSettings.CoverageCalculationSettingsSource

 public enum CoverageCalculationSettingsSource
 {
     RadioPlanSettings,   // As defined in radio plan layer Settings
     RadioNet,            // Use Coverage calculation settings from the radio's radio net if defined
 }

Coverage calculation for a Radio is started with

Result<Guid> jobId = await _radioPlanLayer.RadioCoverage.StartCoverageCalculationForRadioAsync(radio);

If successful, jobId returns a Guid to identify the job. Otherwise, the result returns an error message. Progress can be checked by subscribing to the event RadioCoverage.CovDataUpdateProgress.

_radioPlanLayer.RadioCoverage.CovDataUpdateProgress += CoverageDataUpdateProgress;

...

private void CoverageDataUpdateProgress(object sender, CalculationJobStatus calculationJobStatus)
{
    if (calculationJobStatus.IsCompleted)
    {
        ProgressValue = 0;  // the clients progress indicator
    } 
    else
    {
        ProgressValue = calculationJobStatus.TotalPercentCompleted;
    }
}

Abort Coverage Calculations

Coverage calculations can be aborted for a specific job by RequestAbortCoverageDataJob(jobId),

or as a general abort request by RequestAbortCalculationJobsAsync()

Automatic Update

Changes to the Site or the Radio may invalidate the coverage data. This will apply to changes like:

  • Site position
  • PositionOffset of the Antenna
  • Frequency
  • Height of the Antenna

When such changes are detected, the current coverage data is invalidated. If a coverage plot for a Radio is visible, it will disappear if any of these properties are changes.

If RadioPlanSettings.AutomaticCoverageCalculation is true, a new coverage calculation will start automatically to create that valid coverage data. Progress can be detected by the RadioCoverage.CovDataUpdateProgress event.

When calculation is finsihed, the plot will reappear if it was visible before the invalidating change.

Other changes to a Radio that affects the coverage area will not cause invalidation of the coverage data, but will cause a rescale of the coverage area on-the-fly. Examples are:

  • TxPower
  • Loss
  • Antenna
  • Antenna Direction
  • Antenna Tilt

Propagation Models

5G_UHF+

A high-band empirical propagation model, derived from measurement data and tuned to a specific dataset or regulatory use.

Core characteristics

  • Type: Based on the empirical Okumura-Hata radiopropagation model
  • Uses DTM, Clutter and building height raster maps
  • Tuned for UHF, lower SHF ranges and land based predictions

When to use it

✅ Cellular radio networks, e.g. 5G, radio systems in the UHF range.

❌ Avoid when: Coverage area is mainly over water and if only DTM map data is available

ITM (Longley–Rice / Irregular Terrain Model)

A general-purpose terrain-aware propagation model combining electromagnetic theory with empirical/statistical corrections.

Core characteristics

  • Frequency: ~20 MHz – 20 GHz [github.com]
  • Type: Hybrid (physics + empirical)
  • Models LOS, diffraction, and scatter regimes

When to choose it

✅ Use when: * You need terrain-aware predictions * You want link-level or detailed coverage analysis * You need one model across wide frequency ranges

❌ Avoid when: * You need very fast, coarse coverage * You lack terrain/profile data

Mental model:

“Engineering-grade propagation model balancing physics and statistics.”

ITU‑R P.1546

What it is

An empirical, large-scale propagation model for point‑to‑area coverage prediction, based on measured field‑strength curves.

Core characteristics

  • Frequency: 30 MHz – 4 GHz [web.stanford.edu]
  • Type: Empirical (curve-based)
  • Prediction: Area coverage (not path-specific)
  • Outputs: Field strength, path loss [qsl.net]
  • Statistical: Time % and location % variability [dxlook.com]

When to choose it

✅ Use when: * You need wide-area coverage prediction * You want ITU/regulatory-aligned results * You are working in broadcast / macro-scale planning

❌ Avoid when: * You need site-specific or path-accurate predictions * Terrain detail must be explicitly modeled

Mental model:

“Statistical broadcast coverage model based on measured propagation curves.”


Radix‑MKE

What it is

A deterministic diffraction model using multiple knife-edge (Deygout) calculations to evaluate terrain obstruction loss.

Core characteristics

  • Type: Deterministic (geometry-based)
  • Explicitly models:
    • Terrain obstacles as knife-edges
    • Multi-obstacle diffraction chains
  • Typical accuracy: ~±3 dB in suitable terrain [deepwiki.com]

When to choose it

✅ Use when: * Terrain obstructions (mountains/ridges) dominate * You need path-specific analysis * Working in VHF / lower UHF regimes

❌ Avoid when: * You need large-area statistical coverage * Terrain is flat (overkill) * You need clutter/building modeling

Mental model:

“Explicit terrain diffraction solver for obstructed paths.”

Quick selection comparison

Model Type Best for Avoid when
P.1546 Empirical (area) Broadcast / large coverage Site-specific accuracy
ITM Hybrid Terrain-aware links & coverage No terrain data
H01 Highband Empirical (tuned) Standardized high-band scenarios Outside dataset
L0X LowBand Empirical Low-band coverage Higher frequencies
L01 Lowband (2016) Empirical (versioned) Legacy reproducibility General use
Radix‑MKE Deterministic Obstructed terrain paths Large-area modeling

Practical decision rule

  • Macro coverage / broadcast: → P.1546
  • General-purpose with terrain: → ITM
  • Strict regulatory / reproducibility: → H01 / L01 / L0X
  • Terrain-obstructed path analysis: → Radix‑MKE