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Multi-Cluster Frequency Correlation Modelling for Tactical VHF Channels in Mountainous Terrain

This paper addresses the problem of modelling the behaviour of wideband VHF channel measurements collected in mountainous regions of Norway. A considerable number of measurement results reveal non-monotonic behaviour of the calculated complex frequency correlation function (FCF), which can be attributed to the multipath clustering effect in the channel power delay profile (PDP). This paper presents a cluster-based FCF model. It is shown that the correlation properties of the measured FCF fit those of the proposed model very well, even when rapid oscillations in the FCF are present. The paper also presents example parameter distributions for the model enabling the radio performance in mountainous environments to be analyzed and simulated. Furthermore, a framework that is able to automatically cluster multipath components (MPCs) and decide on the number of clusters is introduced.