【摘要】 本文推导非同步 Ｃ Ｄ Ｍ Ａ 系统多址干扰表达式，计算正交码调制码组相关性对多址干扰的影响。提出一种改进型 Ｗ ａｌｓｈ＋ Ｇ Ｍ Ｗ 正交码组，分析比较 Ｗ ａｌｓｈ 正交码组和 Ｗ ａｌｓｈ＋ Ｇ Ｍ Ｗ 正交码组应用于非同步 Ｃ Ｄ Ｍ Ａ 系统的性能。计算机模拟结果表明应用改进型正交码组时系统性能获得改善。更多还原

【Abstract】 The performance representation indicating the effects of correlation of orthogonal code modulation sequences on MAI suppression in nonsynchronous CDMA system has been derived.Furthermore,an improved orthogonal codes called Walsh+GMW sequences is proposed in this paper.Analysis and comparison of the performance between nonsynchronous CDMA systems using Walsh and Walsh+GMW orthogonal sequences are presented.Computer simulation results show that the system performance using Walsh+GMW sequences is improved.更多还原