A novel frequency reuse technique for in-building small cells in dense heterogeneous networks

作者：Saha Rony Kumer; Aswakul Chaodit^*

来源：IEEJ Transactions on Electrical and Electronic Engineering, 2018, 13(1): 98-111.

DOI：10.1002/tee.22503

• algorithm
• clustering
• dense network
• eICIC
• femtocell
• in-building
• resource reuse
• small cell

In this paper, we address the important issue of reusing frequency resource in femtocells deployed in dense multi-floor buildings over a large urban macrocell coverage to enhance network capacity and spectral efficiency using almost blank subframe (ABS)-based enhanced inter-cell interference coordination (eICIC) technique. Femtocell clustering and modeling an optimum number of ABS (OPNA) are, however, two major challenges to reuse frequency in femtocells deployed in buildings using ABS-based eICIC. In this paper, we address these challenges by exploiting the high external wall penetration loss of any buildings and in-between distance of neighboring buildings, and propose a femtocell clustering approach by considering all femtocells in any buildings as a femtocell cluster to avoid an additional computational complexity from clustering. We develop a frequency reuse and scheduling algorithm (FRSA) for an arbitrary number of ABSs for a multi-tier network, which consists of in-building femtocells and outdoor picocells in the coverage of an urban macrocell. We then propose a model for estimating the OPNA and derive an OPNA per femtocell cluster basis under two schemes, namely adaptive OPNA and non-adaptive OPNA, in order to vary the number of ABSs imposed on femtocells within a building dynamically based on the presence of indoor macrocell users within the building to avoid cross-tier interference with femtocells. An optimization algorithm for OPNA schemes is developed, and its implementation aspects are discussed. The impact of varying the number of ABSs and femtocells per building on the throughput performance of FRSA is analyzed through an extensive system-level simulation, and the capacity outperformance of the adaptive over the non-adaptive OPNA scheme is shown. Finally, a schematic of the scheduler implementation for FRSA is developed, and the capacity outperformance of FRSA over a number of existing works is shown.

• 出版日期2018-1