Characterizing the effects of multipath dispersion on digital radios

The author describes a method of accounting for the dispersiveness of fading in predicting the outage of digital radios. The method is based on a composite fade margin, which depends on both path and radio characteristics. The effects of dispersion enter through a dispersive fade margin which is expressible as a difference between an equipment characteristic, namely the reference dispersive fade margin, and a characteristic of the fading on the path, namely the relative dispersion factor or, equivalently, the dispersion ratio. It is concluded that the reference dispersive fade margin provides a well-defined, standard basis for characterizing a radio system and for predicting its performance on a hop of known dispersiveness