Comparison of different 1-D interpolation algorithms for estimation of shadow fading

Lack of coordination between cognitive radio system and primary users requires learning about RF propagation features in the environment as key input to adaptive system parameters. Channel gain cartography is to enable having RF propagation maps. The challenging task is how to predict (or estimate) the shadowing of the channel gain maps. In this paper, different 1-D interpolation algorithms are tested against a shadow fading series that exhibits decaying exponential correlation versus distance behaviour. The purpose of this paper is to investigate the validity ranges over which each interpolation algorithm works well to estimate the shadow fading. The tested validity ranges are correlation distance, standard deviation of shadow fading and data density level of measured data.