A Model for the Correlation of Signal Fading and Enhancement

A new approach to the modelling of correlation between fading and enhancement on radio links is proposed. The joint probability density function (PDF) is central to characterising the statistical dependence of the statistics of multiple paths. The proposed method makes use of statistical functions called copulas to generate families of joint PDFs from the single-path cumulative probability distribution functions (CDF). These CDFs are obtained directly from ITU-R Recommendations P.530 and P.452, and so the new model can be seen to extend the ITU-R models to multiple paths. The paper describes a prediction model for joint pair- wise PDFs. The choice of copula function and the parameters of the model are based on recent measurements in the UK.