This paper investigates the diversity gain of a distributed cyclic delay diversity (dCDD) scheme for cyclic-prefixed single carrier systems in non-identical fading channels. Non-identical small-scale fading is assumed in the environment, in which non-identical line-of-sight and non-line-of-sight fading coexist. A condition for dCDD resulting in intersymbol interference free reception at the receiver, is extended to this new channel environment. For an overpopulated system setup, a generalized performance analysis, is not available from existing works, is conducted after developing closed-form expressions for the distribution of the signal-to-noise ratio (SNR) realized at the receiver. Since the order statistics are involved in the statistical properties of the SNR, the corresponding spacing statistics are utilized to derive feasible closed-form expressions. The finalized closed-form expressions are shown to provide very reliable outage probability and spectral efficiency of dCDD for underpopulated and overpopulated systems. An asymptotic performance analysis verifies the maximum achievable diversity of the dCDD even in the overpopulated case within the considered channel environment. Link-level simulations are conducted and these verify the maximum achievable diversity gain.

中文翻译：

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不同衰落信道中分布式CDD系统的分集增益分析

本文研究了非相同衰落信道中循环前缀单载波系统的分布式循环延迟分集 (dCDD) 方案的分集增益。假设环境中存在不完全相同的小尺度衰落，其中不完全相同的视线和不相同的视线衰落并存。dCDD 导致接收器无码间干扰接收的条件扩展到这种新的信道环境。对于人口过多的系统设置，现有工作中没有的广义性能分析是在开发用于接收器实现的信噪比 (SNR) 分布的封闭式表达式之后进行的。由于阶次统计涉及 SNR 的统计特性，相应的间距统计用于推导出可行的封闭形式表达式。最终的封闭式表达式被证明可以为人口不足和人口过多的系统提供非常可靠的 dCDD 中断概率和频谱效率。渐近性能分析验证了 dCDD 的最大可实现多样性，即使在考虑的信道环境中人口过多的情况下也是如此。进行链路级模拟，并验证最大可实现的分集增益。渐近性能分析验证了 dCDD 的最大可实现多样性，即使在考虑的信道环境中人口过多的情况下也是如此。进行链路级模拟，并验证最大可实现的分集增益。渐近性能分析验证了 dCDD 的最大可实现多样性，即使在考虑的信道环境中人口过多的情况下也是如此。进行链路级模拟，并验证最大可实现的分集增益。