Coloring based access-Backhaul scheduling in ultra dense networks with flexible duplex

Yuwei Yao, Hui Tian, Gaofeng Nie, Zhaolong Huang

Abstract: Due to the flexible deployment, in-band wireless backhaul solutions are preferred to the small cells in the ultradense networks (UDN). This paper manages the scheduling issues of in-band wireless backhaul in UDN by jointly considering the effect of access-backhaul link constraint, the interference and the minimum user data rate requirement. The scheduling problem that aims at maximizing the system throughput is formulated, whose solution is NP-hard. To reduce the calculation complexity and obtain a practical scheduling solution, A scheme named as coloring based access-backhaul scheduling (CBABS) is proposed. In CBABS, the minimum data rate requirements are satisfied by a QoS guarantee algorithm, the interference is managed by coloring algorithm (CA), the matching is done by ensuring the same data rate on access and backhaul link. Simulation results show that 98% of users' minimum downlink data rate requirements and 99% of users' minimum uplink data rate requirements are satisfied. The RB utility ratio is improved by 30% in CBABS compared to traditional scheduling scheme.