Cooperative Quantization for Two-UserInterference Channels

We introduce cooperative quantizers for two-user interference channels where interference signals are treated as noise. Compared with the conventional quantizers where each receiver quantizes its own channel independently, the proposed cooperative quantizers allow multiple rounds of feedback communication in the form of conferencing between receivers. For both time-sharing and concurrent transmission strategies, we propose different cooperative quantizers to achieve the full-channel-state-information (full-CSI) network outage probability of sum rate and the full-CSI network outage probability of minimum rate, respectively. Our proposed quantizers only require finite average feedback rates, whereas the conventional quantizers require infinite rate to achieve the full-CSI performance. For the minimum rate, we also design cooperative quantizers for a joint time-sharing and concurrent transmission strategy that can approach the previously established optimal network outage probability with a negligible gap. Numerical simulations confirm that our cooperative quantizers based on conferencing outperform the conventional quantizers.