Radio Propagation Models

To find an accurate model for propagation losses is an important issue when planning a mobile radio network. Two strategies for predicting propagation losses are in use these days; one is to derive an empirical propagation model from measurement data, and the other is to use a deterministic propagation model. Atoll uses a macrocell propagation model, the Standard Propagation Model (SPM), based on empirical formulas and a set of parameters.

When Atoll is installed, the SPM parameters are set to their default values. However, they can be adjusted to tune the propagation model according to actual propagation conditions. This calibration process of the Standard Propagation Model facilitates improving the prediction reliability.

EDX SignalPro lets you select from an extensive set of over 20 published propagation models, customize the coefficients of selected empirical models, or create your own proprietary propagation models with an external dynamic link library. All models have adjustable environmental and reliability parameters. Further, you can select a unique model for every base station sector in your study, or use a single model for the entire study.

With both Atoll and SignalPro users have the ability to select specialist propagation models from third party suppliers.

Aster

Aster, developed by Forsk, is a high-performance propagation model for Atoll that supports macro, micro, and small cell urban propagation scenarios. Aster includes advanced ray-tracing propagation techniques and combines high accuracy with superior calculation speed.

Scope

  • Support for all radio access technologies (GSM, UMTS, LTE, …)
  • Support for frequencies ranging from 150 MHz to 5 GHz
  • Support for all types of cells with pre-configured and user-defined parameters: macro, micro, and small cells
  • Support for all types of propagation environments: rural, suburban, urban, dense urban

Propagation Modelling

  • Vertical diffraction over roof-tops
  • Horizontal diffraction/reflection based on ray-launching
  • Ray-tracing calculation on raster data as well as on vector building data

Configuration & Calibration

  • Support of multi-threading and distributed computing
  • Automatic calibration using CW measurements

Crosswave

CrossWave is a high-performance universal propagation model developed by Orange Labs. It supports all wireless technologies and all types of environments, from rural to dense urban areas.

CrossWave uniquely combines accuracy with calculation speed; it can be used as a pre-calibrated propagation model but it also features a powerful integrated automatic calibration function.

Propagation Conditions

  • Vertical diffraction
  • Horizontal guided propagation (micro-cells)
  • Reflections on mountains

Specifications

  • All technologies are supported (eg. GSM, CDMA, LTE…)
  • Frequency Range 200 MHz to 5 GHz
  • Reflections on mountains
  • All types of situations: macro, mini and micro-cells
  • All environments: rural, suburban, urban, dense urban
  • Support of all Atoll raster formats
  • Support of 3D building data

Configuration & Calibration

  • Support of multi-threading and distributed computing
  • Pre-calibration based on Orange Lab experience of various countries and propagation conditions
  • Automatic calibration using CW measurements

Volcano

Siradel

Volcano is available for both Atoll and SignaPro and provides highly accurate radio coverage and interference calculations for complex network designs. With the advent of wideband technologies (3G, WiMAX, BFWA) and the convergence of telecom and broadcast applications (DVB-T, DVB-H), there is a growing need for accurate and flexible prediction techniques accounting for both outdoor and indoor units (see prediction for DVB network SFN coverage above). These include indoor base stations that can interfere with the outdoor network or indoor User Terminals belong to a mobile or point-to-multipoint FWA system (eg a WiMAX network)

There is also a need for handling computation-intensive applications such as the optimisation of several thousand sites requiring multiple runs of the same predictions with different parameters.

Volcano 2.6 makes this easy with its ability to handle clutter-based pre-defined prediction zones and wideband outputs. Volcano can analyse indoor prediction only or optimise a network by focusing on some areas only thus making faster predictions.

Users can also get access to log files containing a variety of wideband outputs that can be used for more advanced system-level simulations. Such predictions can simulate Smart Antenna systems or estimate the downlink orthogonality factor (key to interference simulation in WCDMA systems)

WinProp

Winprop

WinProp’s DPM (Dominant Path Model) is available for Atoll and focuses on all relevant propagation effects and combines high accuracy with computation times in the range of empirical models. An auto-calibration with measurements allows a simple tuning of DPM’s parameters.

To achieve the highest accuracy for macro, micro, and pico cells, WinProp considers simultaneously different types of databases (topography, clutter, vector buildings) - depending on their availability in rural, suburban, and urban environments as well as inside buildings. So all air interfaces (2G, 2.5G, 3G, HSPA, LTE, WiMAX), arbitrary antenna heights, all transmitter types, and all cells in the whole network can be planned with the WinProp propagation model.

Today, wireless networks must provide high data rates inside buildings. Therefore the actual buildings cannot be ignored in the predictions. The waveguiding in street canyons as well as the diffractions at roofs and wedges are dominating the wave propagation in urban scenarios. WinProp’s DPM considers optionally the vector data of the buildings to include the most important propagation effects. This leads to a very high accuracy.

In-Building coverage is very important and WinProp offers two options for the indoor coverage: Either empirical indoor models without consideration of indoor walls or CNP (Combined Network Planning) including indoor walls.

Very large areas can be predicted in a hybrid mode. Around the transmitter with the DPM and far away with Atoll’s standard propagation model. A weighted bilinear interpolation between the two models leads to a smooth transition.