Abstract:

In practical communication systems, the prefect channel state information (CSI) is hardly obtained by transmitters owing to imperfect estimate or feedback of the channel coefficients. In order to mitigate the adverse impact of imperfect CSI on bit error rate， based on the constraint of zero-forcing channel error, a robust minimum interference leakage algorithm is proposed for multi-cell multi-user multi-input multi-output system. The formulation of system sum rate is derived under new objective constraint with channel error. Simulations show that if the imperfect CSI is known, the performance on bit error rate and average sum rate of the user in cell edge can be improved by the proposed robust algorithm, especially at the high signal noise rate values.

Key words: interference alignment, channel error, multi-cell, long term evolution system, system sum rate