A shadowing-aware Density_Map for location estimation using COB in non-uniformly populated cellular systems

The presence of non-line-of-sight (NLOS) propagation poses significant problems in positioning a mobile terminal within cellular communication systems. Count-of-Beacon (COB) is a new radiolocation technique where the existence of NLOS propagation does not degrade the precision of the estimated position. However, non-uniformity of subscribers´ distribution negatively affects the performance of the COB technique. The Density_Map of each cell can be used to lighten the impact of nonuniform distribution of subscribers. However, the accuracy of the Density_Map is highly reliant on the propagation conditions of the wireless environment. This paper analyzes the sensitivity of the Density_Map to the deviation of the attenuation that signals experience in shadow fading environments. This analysis is then used to redefine the Density_Map. Simulation results are used to verify the validity of the new defined map when the environment is suffering from high shadowing.