Software for site specific propagation prediction

The design of cellular wireless communication systems is influenced by the propagation characteristics of the channel and their effect on transmitted signals. The multipath propagation characteristics of a channel, except under simple transmission conditions, limits the design of emerging cellular systems. Once the propagation conditions are understood, systems can be designed more efficiently in terms of site layout and frequency planning, to reduce deployment costs and improve performance.

A software tool for site specific radio propagation prediction is being developed at the Mobile and Portable Radio Group, Virginia Tech. The objective of this research is to develop re-usable program modules that can be utilized to implement several functional features of the software.

This thesis describes the raster and vector programming libraries that have been developed during this research. These libraries are utilized in the database module, user interface and graphics module and propagation prediction module of the software. Significant among the capabilities that these libraries provide are the ability to store and retrieve raster and vector data from the database, import measured and predicted data available in standard data formats into the database, obtain user inputs through an interactive mechanism, display images of site specific information at various resolutions, and enable the user to view and analyze measured and predicted data.

This thesis also presents the data format, that has been defined during this research, to acquire and import contour and elevation information of buildings. The SISP General Data Format (GDF), that has been developed, to facilitate import of measured and predicted data has also been described. The Hierarchical Data Format (HDF), developed by the National Center for Supercomputing Applications (NCSA), has been adopted to store measured and predicted data in the database. The programming techniques used to retrieve and display data stored in this format are also outlined in this thesis.

SISP has been developed on Sun Sparc workstations. Details of the function libraries that have been developed, programming methodologies employed, and data formats that have been defined for site specific and measured and predicted RF data are included in this thesis.