Energy and spectral efficient Doppler diversity transmissions in high-mobility systems with imperfect channel estimation
Energy and spectral efficient Doppler diversity transmissions in high-mobility systems with imperfect channel estimation
复制标题
信道估计不完善的高移动性系统中的能量和频谱高效多普勒分集传输
DOI：
10.1186/s13638-015-0374-6
复制
发表时间：
2015-05
影响因子：
2.6
通讯作者：
Zhou WX
中科院分区：
文献类型：
--
作者：
Zhou Weixi;Fan Pingzhi;Wu Jingxian;Zhou WX
本文研究了在不完全信道状态信息（CSI）下能量和频谱有效的多普勒分集传输。高移动性通信系统中的快速时变衰落引入了多普勒分集，可以有益于系统性能。另一方面，快速时变信道的估计和跟踪更加困难，因此，在高移动性系统中，信道估计误差会严重降低系统性能。信道估计误差和多普勒分集之间的权衡使用两种预编码方案，一个简单的重复码，和速率1多普勒域复用（DDM）计划进行了研究。重复码可以以较低的频谱效率为代价实现最大的多普勒分集，而DDM方案可以实现能量和频谱有效的多普勒分集传输。与许多其他多普勒分集系统，假设完美的CSI，我们明确考虑不完美的CSI的设计和性能的预编码方案的影响。通过研究信道估计误差的统计特性，提出了两种方案的最优和次优接收机。接收机的分析错误概率被表示为多个系统参数的函数，例如最大多普勒扩展、用于信道估计的导频符号的百分比、导频和数据符号之间的能量分配等。分析和仿真结果表明，两种预编码方案都可以通过优化各种参数来实现最大多普勒分集阶数，即使犯罪现场调查并不完美
This paper studies energy and spectral efficient Doppler diversity transmissions in the presence of imperfect channel state information (CSI). Fast time-varying fading in high-mobility communication systems introduces Doppler diversity that can benefit system performance. On the other hand, it is more difficult to estimate and track fast time-varying channel; thus, channel estimation errors might seriously degrade system performance in high-mobility systems. The trade-offs between channel estimation errors and Doppler diversity are studied by using two precoding schemes, a simple repetition code, and a rate 1 Doppler domain multiplexing (DDM) scheme. The repetition code can achieve the maximum Doppler diversity at the cost of a lower spectral efficiency, and the DDM scheme can achieve the energy and spectral efficient Doppler diversity transmissions. Unlike many other Doppler diversity systems that assume perfect CSI, we explicitly consider the impacts of imperfect CSI on the design and performance of both precoding schemes. Optimum and suboptimum receivers for both schemes are developed by studying the statistical properties of channel estimation errors. The analytical error probabilities of the receivers are expressed as functions of a number of system parameters, such as the maximum Doppler spread, the percentage of pilot symbols for channel estimation, the energy allocation between the pilot and data symbols, etc. The analytical and simulation results indicate that both precoding schemes can achieve the maximum Doppler diversity order through the optimization of the various parameters, even in the presence of imperfect CSI.
登录
查看更多内容
影响因子：
8.3
作者：
S. Savazzi;U. Spagnolini
通讯作者：
S. Savazzi;U. Spagnolini
DOI：
10.1109/glocom.2013.6831591
发表时间：
2013-12
期刊：
2013 IEEE Global Communications Conference (GLOBECOM)
影响因子：
--
作者：
Ning Sun;Jingxian Wu
通讯作者：
Ning Sun;Jingxian Wu
DOI：
10.1109/26.898252
发表时间：
2001
期刊：
IEEE Trans. Commun.
影响因子：
--
作者：
A. Stamoulis;G. Giannakis;A. Scaglione
通讯作者：
A. Stamoulis;G. Giannakis;A. Scaglione
DOI：
10.1109/milcom.2013.160
发表时间：
2013-11
期刊：
MILCOM 2013 - 2013 IEEE Military Communications Conference
影响因子：
--
作者：
Ning Sun;Jingxian Wu
通讯作者：
Ning Sun;Jingxian Wu
DOI：
10.1109/icc.2014.6884267
发表时间：
2014-06
期刊：
2014 IEEE International Conference on Communications (ICC)
影响因子：
--
作者：
Weixi Zhou;Jingxian Wu;P. Fan
通讯作者：
Weixi Zhou;Jingxian Wu;P. Fan