Random-backoff enabled distributed scheduling in CoMP systems

Coordinated Multi-Point transmission (CoMP) is one of the key technologies in LTE-Advanced (LTE-A) systems to effectively improve the spectral efficiency of cell-edge users. In this paper, we propose a random-backoff enabled distributed scheduling scheme in CoMP systems, which aims at combating inter-cell interferences and efficiently enhancing the cell-edge users´ spectral efficiency. Specifically, each base station (BS) uses the dynamic clustering algorithm to identify the cells causing the strongest interferences to its scheduled user. Then, in order to eliminate the strong interferences, each BS sends the coordination requests to BSs of these interfering cells. After exchanging coordination requests, each BS decides whether to continue transmissions for its scheduled user based on the coordination requests and the number of coordinated cells. If there are still collisions after coordination, the BSs of the corresponding cells use random backoff strategies for collision avoidance. Simulations results show that our proposed distributed scheme outperforms the conventional schemes in terms of the spectral efficiency of cell-edge users.