Importing and Modifying Urban Database in Wallman
WinProp is a comprehensive and leading simulation tool in the domain of wireless propagation and radio network planning. For a very accurate result, it is very important to create an accurate database that has all the right geometry. We can distinguish the types of database into an indoor database or Urban/outdoor database.
Indoor and urban databases are similar – except for the orientation of the objects. In urban databases, the basic element is a polygonal cylinder which is built with many planar objects. Only the roof of the cylinder is defined and used. All walls are generated during the propagation analysis when they are needed. They consist always of four corners and are vertical. This limitation of the data format saves a lot of memory and is therefore very efficient for large databases with several thousands of buildings. In indoor databases the orientation of objects is arbitrary - this is the basic difference to the urban databases. To model a simple building with four walls and a flat roof, five objects are needed and each object has four corners. Therefore, indoor databases are limited to smaller areas with fewer objects. But the environment can be as arbitrary as possible – ranging from a small campus down to a single room.
In this blog, we will focus on urban database. We shall demonstrate how a dxf file can be imported in Wallman. The video at the end of this blog also demonstrates how to modify the imported building data using special functions in Wallman
Urban Vector Database
Urban vector databases contain a description of all buildings and vegetation areas in an urban environment. The buildings are described by polygonal cylinders, buildings with arbitrary shapes can be used. The building database offers the following features:
- Each polygon can have an arbitrary number of corners
- At least 3 corners are required to define a valid polygon (building).
- Each building has a uniform height (polygonal cylinder). The height is either relative to the ground or absolute above sea level. Absolute height values require additionally a topographical database.
- Flat rooftops are used (horizontal planes).
- Each building has a single set of material properties which are used for the whole building.
- The polygon of a building must not intersect itself.
Conversion of Database
With WallMan it is possible to convert databases from many common database formats to the WinProp format. The following file formats are supported:
- WinProp urban buildings ASCII (.oda)
- Vector data ASCII format (.vda)
- Arcview Shapefile (.shp)
- Open Street Map (.osm)
- AutoCAD (.dwg, .dxf)
- MapInfo File (.mif, .tab)
- Aircom Asset / NSN NetAct (single file)
- Aircom Asset / NSN NetAct (index file)
- MSI Planet Building Data (single file)
- Geography Markup Language (.gml)
Please see the below video for reference. The dxf and odb files are attached to this blog for user access. Please reach out to Altair support for more details and questions.