Interference cancellation for common code multiple access transmission

作     者：Inui, S Nakagawa, M 

作者机构：Keio Univ Dept Elect Engn Yokohama Kanagawa 2238522 Japan 

出 版 物：《IEICE TRANSACTIONS ON COMMUNICATIONS》 (电子情报通信学会汇刊，英文版，B:通信)

年 卷 期：1998年第E81B卷第9期

页      面：1741-1748页

核心收录：

学科分类：0810[工学-信息与通信工程] 0808[工学-电气工程] 0809[工学-电子科学与技术（可授工学、理学学位）] 08[工学] 

主　　题：side-lobe canceller common code chip shift transmission perfect/half/no collision 

摘      要：In this paper, we propose a multiple access technique using a simple interference canceller for common code transmission. In the proposed system, we adopt a common code for a receiver oriented system. All the transmitters utilize the same pseudo noise (PN) code to communicate with a receiver. Here the receiver structure becomes very simple with only one matched filter (MF). The proposed system has two very important merits. One is to avoid packet collisions by means of an interference cancellation method based on a common code chip shift transmission technique. That is, in order to avoid interference, which occurs because all the received signals have the same PN code, the same data with different timing are transmitted in two channels. In this study, we define and evaluate three types of packet collision which can be reduced by the canceller. The other merit is to reduce the system degradation due to the correlation side-lobes by means of a side-lobe canceller. In spread spectrum (SS) communication systems with PN codes like M-sequences, the correlation side-lobes appear at the detector in the case of the polarity data changing from +/-1 to -/+ 1. The side-lobes degrade the system quality. Therefore in this system a interference canceller operates to cancel the correlation side-lobes and attempts to reduce the system degradation. Finally, by our cancellation method it becomes possible to realize a simple multiple access using only one PN code under the condition of a receiver oriented system without a base station.