Project on CDMA and Array Antennas for Mobile Communications

本研究旨在促进日本与欧洲在自适应阵列天线和基于扩频技术的码分多址（CDMA）领域的国际合作，为克服移动通信等无线通信需求的快速增长所带来的频谱短缺问题提供极为有用的对策。例如，在CDMA技术中，(1)提出了多媒体通信质量评价的优化准则和无线通信信道的建模方法；(2)提出了多媒体CDMA无线通信系统流量方差的测量方法和对单个媒体的处理增益和传输功率的自适应控制方法；(3)提出了基于自适应数字滤波器和自适应阵列天线的空域和时域信号处理方法，以抑制窄带干扰和衰落。其次，在阵列天线中，(1)时变多径衰落信道在空间和时间域的建模；(2)基于自适应阵列天线应用的频率效率提高分析；(3)时空最优均衡器、接收机、信道编解码的提出与分析；(4)自适应阵列天线架构和自适应算法的提出与评价；(5)在CDMA环境中的应用与性能分析。

The aim of this study is to international cooperation between Japan and Europe in fields of adaptive array antennas and CDMA (Code Division Multiple Access) based on spread spectrum technique in order to provide extremely useful countermeasures to overcome a lack of frequency spectrum due to rapid increase of demands in wireless communications such as mobile communications. For instance, in a CDMA technique, (1) The way of leading the optimization criterion of the communication quality evaluation of the multimedia and modeling the wireless communication channel, (2) Proposal of a method of measuting traffic variance of multimedia CDMA wireless communication systems and a method of adaptive controlling the processing gain and transmission power for individual media, (3) Proposal of the signal processing in space and time domains based on adaptive digital filter and adaptive array antenna for rejection to narrow band interference and fading. Second, in a array antenna, (1) Modeling of time-varying multipath fading channel in space and time domains, (2) Analysis of improvement of frequency efficiency based on application of adaptive array antennas, (3) Proposal and analysis of space and time optimum equalizer, receiver, channel coding and decoding, (4) Proposal and evaluation of adaptive array antenna architectures and adaptive algorithms, (5) Application and performance analysis to CDMA environment.