Professor Tsutomu Takeuchi

Area and Subject Taught Radio Communication Engineering
Research Theme(s) Wireless Communication for Digital Multimedia
Academic Degrees Doctor of Engineering, Kyoto University
Keywords for Research Field Mobile Communication, Multipath Propagation in urban areas and indoor environments, Wireless LAN
Office Phone Number Not Public
e-mail Not Public

Research Overview

The recent advances in wireless communication engineering enable the fourth generation mobile phones and the high-speed, more than 100Mb/s, wireless LAN. However, the multipath propagation of radio propagation characteristics in urban areas and indoor environments is an eternal problem to be overcomed to improve the system performance of wireless communication systems.
In order to mitigate the mutipath propagation characteristics of radio wave, we have developed a test equipment for measuring the time delay characteristics of radio wave propagation in indoor radio environment which resolves 0.5 ns time delay between the multipath waves by using the auto-correlation characteristics of pseudo noise used in CDMA system. This equipment enables to estimate the system performance of new radio communication system by calculating the bit error rate performance by computer simulation in real radio environment based on the measured radio wave propagation characteristics. In recent research topic of wide interest in wireless communication is a so-called MIMO (multi-input multi-output) system. We are also trying to analyze the indoor radio propagation characteristics featuring the MIMO transmission characteristics by using the switched MIMO transmitting and receiving antennas. And also our recent research topic is an ultra-wideband indoor radio system employing the anti-multipath modulation technique which is our unique idea for realizing the 1Gb/s data transmission speed.

Notable Publications and Works in the Last Three Years

Tsutomu Takeuchi and Hirohito Mukai,“ An Ultra Wide Band Channel Sounder for Indoor Wireless Propagation Environments,” IEICE Transaction on Electronics, vol.E87-C, no.9, pp.1467-1468, Sep. 2004.