Multi-User MIMO Multi-Cell Systems: Finite SNR Rate Loss Analysis

The rate loss gap due to imperfect channel state information at the transmitter in a multi-user MIMO multi-cell system is analyzed. Results from [1] are generalized for systems incorporating user selection and an arbitrary beamforming scheme. It is found that, if the transmitter is allowed to perform a user selection and uses an arbitrary beamforming scheme, the same scaling of the rate loss gap can be achieved if the feedback bits are doubled.