Efficient Maximum Likelihood Detection with Imperfect Channel State Information for Interference-limited MIMO Systems

Advanced interference-aware detectors are being studied for 3GPP LTE-A to mitigate interference in multi-cell networks. In practical applications, imperfect channel estimates over noisy channels are inevitable. Ignoring them leads to severe performance degradation. The aim of this paper is to investigate a method for an interference-aware maximum likelihood detector to mitigate the impact of channel estimation errors. Simulation results for typical 3GPP LTE/LTE-A show the new method can provide flexibility and ability to deal with the channel estimation errors and to achieve a better trade-off between complexity (e.g., in terms of operations) and performance (e.g., in terms of error rate) in interference-limited scenarios. The proposed lowcomplexity CEN-ML sphere detector can have a gain of more than 5dB than the other investigated detectors for 16-QAM at a target coded block error rate of 0.01.