Rate Loss Analysis for Precoder Feedback in Interference Channel with Imperfect CSI

In this paper, we derive the rate loss upper bound for precoder feedback when imperfect channel state information (CSI) is available in interference channel. The upper bound shows that the loss caused due to uncertainty in the channel is proportional to the SNR. The quantization with chordal distance shows that rate loss due to quantization reduces with the increase in the level of uncertainty. And so, the less feedback bits are needed for higher uncertainty in the channel. The simulation results show that the imperfect CSI limits the sum rates achievable which can be obtained with less feedback bits with the increase in uncertainty variance.