Precoder Quantization vs Channel Quantization in Interference Channel with Limited Feedback

In this paper, we compare the precoder and channel feedback in interference channel (IC) when interference alignment (IA) is used. In literature, the channel direction has been quantized and fed back in IC. Here, we consider the precoder quantization and feedback (PQFB) in IC, and seek its benefits over channel feedback. The involvement of IA (where the alignment is sensitive to channel changes) and comparison of required time slots, codebook size and feedback bit rate, show that PQFB is a better choice. The theoretical rate loss for both schemes show that precoder feedback gives less loss in sum rate as compared to channel direction feedback. These results are verified with simulations.