Interference-Aware Scheduling in the Synchronous Cellular Multi-Antenna Downlink

Abstract

Abstract-We consider the downlink of a multi-user MIMO OFDM system in a cellular environment, where users are scheduled to the transmission resources in frequency and space. Targeting a practical solution, we assume the use of fixed DFTbased pre-coding beams at the base stations and linear receivers at the multi-antenna terminals. After having received feedback on the frequency-selective interference conditions from all terminals, each base station schedules the terminals to their resources of highest quality while following a fair scheduling policy. It is shown that this rather simple practical concept enables spatial multiplexing transmission for all users in the system, in particular even for users at cell edge. This results in a capacity scaling that is similar to the one known for isolated point-to-point links. Finally, the system is shown to achieve a performance close to the ideal case if proper techniques to estimate the desired and interfering channels are applied.

Spatial Transmission Mode Switching in Multiuser MIMO-OFDM Systems With User Fairness

“…This comparison illustrated that the system effectively achieves high performance, significantly outperforming that of the two reference systems. The scheduling concept introduced here can readily be employed in a multicell environment, where users with different mean SNRs are present, as investigated in [35] and [36]. Note that the elementary functionality of the proposed system concept has already been tested in realtime experiments, which have been conducted in a real-world broadband mobile communication environment; for details, see [37] and [42].…”