Coexistence of the broadcasting satellite service with fixed service systems in frequency bands above 10 GHz

The allocation of certain frequency bands to both the broadcasting satellite service and the fixed service on a primary basis raises the issue of coexistence, whenever the two types of services are located in the same area and no coordination/agreement is effected. Although regulatory institutions have issued general guidelines concerning future systems, the effect of frequency sharing by numerous operating satellite earth terminals should be examined. The present paper provides an analytical methodology for the prediction of the carrier-to-noise plus interference ratio (CNIR) of broadcasting satellite systems, suffering from interference from an adjacent terrestrial link at frequencies above 10 GHz. The proposed model takes into account the aggravation of intersystem interference due to the spatial inhomogeneity of precipitation. A simplified version of the analytical model, useful for back of the envelope computations is also presented. Some interesting case studies are finally examined.