Open AccessAn Adaptive Hot‐Spot Operating Scheme for OFDMA Downlink Systems in Vertically Overlaid Cellular Architecture
Author(s) -
Kim NakMyeong,
Choi HyeSun,
Chung HeeJeong
Publication year - 2006
Publication title -
etri journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.295
H-Index - 46
eISSN - 2233-7326
pISSN - 1225-6463
DOI - 10.4218/etrij.06.0105.0155
Subject(s) - macrocell , telecommunications link , quality of service , throughput , interference (communication) , dimensioning , base station , computer science , computer network , lte advanced , hot spot (computer programming) , engineering , electronic engineering , real time computing , channel (broadcasting) , wireless , telecommunications , aerospace engineering
In vertically overlaid cellular systems, a temporary traffic concentration can occur in a hot‐spot area, and this adversely affects overall system capacity. In this paper, we develop an adaptive hot‐spot operating scheme (AHOS) to mitigate the negative effects from the nonuniform distribution of user location and the variation in the mixture of QoS requirements in orthogonal frequency division multiple access downlink systems. Here, the base station in a macrocell can control the operation of picocells within the cell, and turns them on or off according to the system overload estimation function. In order to determine whether the set of picocells is turned on or off, we define an AHOS gain index that describes the number of subcarriers saved to the macrocell by turning a specific picocell on. For initiating the picocell OFF procedure, we utilize the changes in traffic concentration and co‐channel interference to the neighboring cells. According to computer simulation, the AHOS has been proved to have maximize system throughput while maintaining a very low QoS outage probability under various system scenarios in both a single‐cell and multi‐cell environments.