Toward Spectrum-Energy Efficient Wireless Networks: It is the time to learn from our human being
By: Prof. Fumiyuki Adachi, Tohoku University, Japan
The wireless traffic volume has been increasing rapidly by about 2 times per year. The state-of-the art gigabit wireless technology is strongly demanded. However, the available wireless bandwidth is limited. We need to reuse the same frequency many places, but the co-channel interference will be produced. How to cope with such a rapid increase of wireless traffic while the available frequency bandwidth is limited? Our wireless challenges are to develop frequency- and energy-efficient gigabit wireless communications networks. Now the time of learning to human being came. We, human being, share the same bandwidth of about 4kHz on the globe of 7 billion people to communicate each other. This is the ultimate single frequency reuse. How to suppress the co-channel interference is an important technique to realize the single frequency reuse. The key is very short range communications with very low energy. This is important to minimize the interference to other users. One promising solution is the distributed antenna network where antennas are distributed over an entire service area. Each user chooses nearby antennas to form a very small wireless cell centering each user, i.e., personal wireless cell is formulated. Only a vicinity of a user is illuminated by a very narrow beam or is covered with very weak transmit signal so that the interference to other users is minimized. We want to avoid very complicated resource allocation algorithm. This may be possible by revisiting to the spread spectrum technique. The simple is the best.
About the Speaker
Dr. Adachi is an IEEE Fellow and a VTS Distinguished Lecturer for 2011 to 2013. He was a co-recipient of the IEEE Vehicular Technology Transactions Best Paper of the Year Award 1980 and again 1990 and also a recipient of Avant Garde award 2000. He is a Fellow of Institute of Electronics, Information and Communication Engineers of Japan (IEICE) and was a recipient of IEICE Achievement Award 2002 and a co-recipient of the IEICE Transactions Best Paper of the Year Award 1996, 1998 and again 2009. He was a recipient of Thomson Scientific Research Front Award 2004, Ericsson Telecommunications Award 2008, Telecom System Technology Award 2009, and Prime Minister Invention Prize 2010.