摘要
为了设计出载波间隔只有码片周期倒数一半的多载波直接扩频系统，提出了一类分组零相关窗（ZCW）地址码．此地址码由某些ZCW互补码与扩展矩阵直积得到，每个互补码扩展成一组码，组内码字的相关特性取决于扩展矩阵．不同组之间的码字仍有ZCW．接收机只需对一组码字而非所有码字联合检测．仿真表明，这类分组码在多径信道中以1～2dB的信噪比代价就可几倍地提高传信率．
A novel type of spreading access codes with set-wise zero correlation window（ZCW） is proposed for minimum orthogonal frequency shift multicarrier direct spread code division multiple access （CDMA） system in which the carrier gap is half of the reciprocal of the chip cycle. The proposed codes are constructed through the direct product of some ZCW complementary codes and certain extend matrix. That is, each complementary code is extended to a set of codes. The access codes correlation property of the codes in one set lies on the extend matrix, nevertheless the ZCW still exists between any two codes in any different code sets. The receiver adopts joint detection only for a code-set rather than for all the codes. Simulation results show that data transmission rate can be improved by several times at the cost of 1- 2 dB signal to noise ratio loss in multi-path fading channels.
出处
《北京邮电大学学报》
EI
CAS
CSCD
北大核心
2006年第5期115-119,共5页
Journal of Beijing University of Posts and Telecommunications
基金
国家自然科学基金项目(90604035)
关键词
多载波直接扩频系统
互补码
零相关窗
multicarrier direct spread system
complementary code
zero correlation window
