Scheduling and Power Control for In-Band Full Duplex Communications

Abstract

In this paper, we consider the scheduling problem in In-Band Full Duplex (IBFD) communications for the access link, where only the Base Station (BS) is assumed to have Self- Interference Cancellation (SIC) capability but not the User Equipment (UE). Thus to achieve the gains from IBFD, the BS would need to schedule one downlink (DL) and one uplink (UL) UE. However, due to the UE-to-UE interference from the UL UE to the DL UE, the gains of IBFD may be quite limited unless this interference is mitigated. Thus, an efficient scheduling algorithm is essential to fully realize the gain potential of IBFD. In this paper, we formulate the Non-Cooperative (NC) and Cooperative (CO) scheduling problems to determine the right set of UEs to schedule to maximize the gains of IBFD communications. In the NC problem, each cell independently determines which DL and/or UL UE to schedule on a per-TTI (Transmission Time Interval) basis. In the CO problem, the users to be scheduled are determined in a coordinated fashion across the entire cooperation cluster to handle the UE-to-UE interference across cells. In both these problems, we also allow the scheduler to pick only one transmission direction instead of both if the scheduler determines that that yields the best performance in that TTI. We show that our scheduling algorithms provide significant gain over the baseline algorithm of independently determining the DL and UL UEs to schedule. We also show that the CO scheme provides significant additional gains but at the cost of increased complexity. We find that the NC scheme provides a good trade-off between performance and complexity, and hence may be a good practical scheme to realize the gain potential of IBFD.