An Interference Management Strategy for Dynamic TDD in Ultra-dense Networks
Ultra-dense networks (UDNs) are considered to meet demands for fast increasing throughput requirements per unit area in hotspots. Along with the dynamic variation of the throughput for the uplink/downlink (UL/DL), flexible resource allocation schemes become very important in UDNs based on time division duplex (TDD) for densely deployed access points (APs) and user equipments (UEs). In this paper, we propose a strategy to resolve the interference problem brought by dynamic TDD in UDNs. Firstly, we design a clustering method based on the Chameleon algorithm to reduce the inter-cluster interference. With the clustering results, the throughput requirements of each cluster become similar. Then we adopt a dynamic UL/DL resource allocation (DRA) for small cells in each cluster, with fewer adopted frame structures reaching more users’ throughput requirements adequately. At last, in each cluster, we adopt multi-cell beamforming (MBF) in small cells with the same frame structure to further mitigate inter-cell interference (ICI). Simulation results show that our proposed strategy could achieve satisfactory performance in UL/DL throughput.
KeywordsUDNs TDD Clustering ICI MBF
This work is supported by the National Science and Technology Major Project of the Ministry of Science and Technology of China (2016ZX03001017) and the National Natural Science Foundation of China (61671088).
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