Description: 文章根据频率选择性衰落信道的抽头延迟线模型，将针对平坦衰落信道的CS(周期平稳过程理论)频偏盲估计
算法扩展到了频率选择性衰落信道，并通过仿真证明这种扩展是可行的.仿真结果还表明CS算法不仅有好的抗平
坦衰落能力，而且有很好的杭频率选择性衰落性能.-Article according to frequency selective fading channel tap delay line model, the flat fading channel for CS (cycle stationary process theory) Frequency Offset Estimation Algorithm extended to frequency selective fading channel, and simulation prove that expansion is feasible. Simulation The results also show that the CS algorithm not only has good ability of anti-flat fading, and have a good hang frequency selective fading performance. Platform: |
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Author:motonula |
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Description: 基于期望最大化(EM)的最大后验信道估计算法(MAP)在高信噪比(SNR)下将很难获得较低的估计误差,并且,对于导频辅助的MIMO-OFDM系统,OFDM符号的数据传输效率随着发送天线的增加而明显下降.为改善这两种缺陷,引入一种等效的信号模型来改善高SNR下的估计性能 在相邻多个OFDM符号内使用相移正交导频序列和联合估计来提高系统的数据传输效率和估计性能 根据角域内信道间的独立性来减小噪声对估计的影响.通过仿真实验可知,所提算法具有更小的估计误差和更高的数据传输效率.-Maximum a posteriori(MAP) channel estimation algorithm usually uses expectation maximum(EM) algorithm to decrease the high computation.However,this kind of operation has a difficulty in obtaining ideal estimation performance at high signal to noise ratio(SNR) because of the convergent feature of EM algorithm.In addition,for pilot-based multiple-input multiple-output with orthogonal frequency division multiplexing(MIMO-OFDM) systems,data transmission efficiency of OFDM symbol will be reduced with the increas... Platform: |
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Author:王睿 |
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Description: 针对MIMO-OFDM系统中期望最大化(EM)信道估计算法在高信噪比(SNR)下带来的误差地板(EF)现象,且OFDM符号的数据传输效率随发射天线数的增加而明显降低,提出一种改进的高效EM信道估计算法。该算法首先引入一种准确的等效信号模型并推导出一种修正的EM算法,改善了EM算法在高SNR下的性能 在多个OFDM间利用相位正交导频序列来提高数据传输效率,同时进行联合信道估计以提高估计性能。仿真实验验证了所提算法具有更高的信道估计性能和更高的数据传输效率。-For multiple-input multiple-output with orthogonal frequency division multiplexing(MIMO-OFDM) systems,the error floor(EF) phenomenon at high signal noise rate(SNR) was induced by the expectation maximum(EM) channel estimation algorithm.In addition,the data transmission efficiency was declined obviously with the increasing number of transmit antennas.According to these problems,an improved and efficient EM channel estimation algorithm was pro-posed.Firstly,an accurate and equivalent signal model was introduc... Platform: |
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Author:王睿 |
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