Comparison of Different Spatial Interpolation Techniques of Field Measurements to Construct Radio Environment Map

Abstract

Still, Spectrum has become one of the crucial needs of living in the modern world. Wireless Communication has increased wide prominence in the current years. From cellular voice telephony to wireless access to the internet and wireless home networking, wireless networks have a profound impact on our lifestyle. However, the emerging needs in wireless communications are making the spectrum congested, and hence there might be a shortage of spectrum in the future. Cognitive Radio (CR) is a niche technology to extend the effective utilization of spectrum by the opportunistic usage of idle spectrum resource smartly. To construct REM there are many techniques which can be categorized as direct and indirect methods. Direct methods involve spatial interpolation of the available data on measured locations to estimate the values at unmeasured locations. To estimate different spatial interpolation techniques, the information utilized in this paper is from the WiseProject Measurement Report: “PMSE Protection Measurements in Helsinki City Theatre” and applied interpolation techniques in ArcGIS software such as Inverse Distance Weighting (IDW), Voronoi interpolation, Ordinary, Universal and Indicator Kriging. Precision in estimation is measured using cross validation of root mean square error [RMSE], and it is utilised for the comparative analysis of interpolation methods applied to the field measurement information.