Summary
IEICE Information and Communication Technology Forum
2015
Session Number:SESSION1
Session:
Number:SESSION1-1
Challenges Toward Spectrum-Energy Efficient Wireless Networks
Fumiyuki Adachi,
pp.-
Publication Date:2015-08-31
Online ISSN:2188-5079
DOI:10.34385/proc.22.SESSION1-1
Summary:
Due to recent rapid penetration of smart phones into our society, broadband wireless services have been getting more and more popular. It is said that the wireless traffic volume has been increasing rapidly by about 2 times per year. Because of limited available bandwidth, the spectrum-efficiency has been the most important concern for the last few decades. The available energy, in particular for battery operated user terminals, is also limited. Therefore, the energy-efficiency has become an important issue. However, the spectrum-efficiency and the energy-efficiency are in a tradeoff relationship. To improve the spectrum-efficiency and energy-efficiency simultaneously, the wireless access network may need a significant restructuring. One promising solution is an introduction of small-cell structured network. Both spectrum-efficiency and energy-efficiency can simultaneously be improved by adopting the small-cell structure. However, a wide range of user mobility is problematic; frequent handover will happen. Furthermore, traffic density is not necessarily high everywhere. It is wise to keep the cell size the same as macro-cell network while exploiting more the spatial distribution of users. We are recently investigating two-layer virtual macro-cell network (e.g., a combination of small-cells and macro-cells). There are two approaches to implement the small-cell layer: distributed small base stations and distributed antennas. In this talk, we will overview the wireless evolution, discuss the spectrum-energy efficiency tradeoff. Then, we will introduce the two-layer virtual macro-cell network. Finally, we will discuss about the power on/off management, distributed dynamic channel allocation, and multi-access problems.