  Aggressive frequency reuse in the return link (RL) of multibeam satellite
communications (SatComs) is crucial towards the implementation of next
generation, interactive satellite services. In this direction, multiuser
detection has shown great potential in mitigating the increased intrasystem
interferences, induced by a tight spectrum reuse. Herein we present an analytic
framework to describe the linear Minimum Mean Square Error (MMSE) performance
of multiuser channels that exhibit full receive correlation: an inherent
attribute of the RL of multibeam SatComs. Analytic, tight approximations on the
MMSE performance are proposed for cases where closed form solutions are not
available in the existing literature. The proposed framework is generic, thus
providing a generalized solution straightforwardly extendable to various fading
models over channels that exhibit full receive correlation. Simulation results
are provided to show the tightness of the proposed approximation with respect
to the available transmit power.
