Channel Pre-Inversion and Max-SINR Vector Perturbation for Large-Scale Broadcast Channels

We study channel pre-inversion and vector perturbation (VP) schemes for large-scale broadcast channels, wherein a transmitter has M transmit antennas and is transmitting to K single-antenna non-cooperating receivers. We provide results which predict the capacity of MMSE pre-inversion as K → ∞. We construct a new VP strategy, max-SINR VP (MSVP), which maximizes a sharp estimate of the signal-to-interference-plus-noise ratio. We provide results which predict the performance of MSVP and demonstrate that MSVP outperforms other VP methods. Lastly, we combine MSVP with the low-complexity sorted QR precoding method to show that MSVP has the potential to efficiently deliver data to a very large number of users at close to channel capacity.