The symbol-error-rate（SER） and power allocation for hybrid cooperative（HC） transmission system are investigated.Closed-form SER expression is derived by using the moment generating function（MGF）-based approach.H...The symbol-error-rate（SER） and power allocation for hybrid cooperative（HC） transmission system are investigated.Closed-form SER expression is derived by using the moment generating function（MGF）-based approach.However,the resultant SER contains an MGF of the harmonic mean of two independent random variables（RVs）,which is not tractable in SER analysis.We present a simple MGF expression of the harmonic mean of two independent RVs which avoids the hypergeometric functions used commonly in previous studies.Using the simple MGF,closed-form SER for HC system with M-ary phase shift keying（M-PSK） signals is provided.Further,an approximation as well as an upper bound of the SER is presented.It is shown that the SER approximation is asymptotically tight.Based on the tight SER approximation,the power allocation of the HC system is investigated.It is shown that the optimal power allocation does not depend on the fading parameters of the source-destination（SD） channel and it only depends on the source-relay（SR） and relay-destination（RD） channels.Moreover,the performance gain of the power allocation depends on the ratio of the channel quality between RD and SR.With the increase of this ratio,more performance gain can be acquired.展开更多
分析了在Gamma-Gamma分布下基于脉冲位置调制(pulse position modulation,PPM)方式的多输入输出自由空间光学(multiple input multiple output free space optics,MIMO-FSO)通信系统模型。首先推导了单输入单输出(single input single o...分析了在Gamma-Gamma分布下基于脉冲位置调制(pulse position modulation,PPM)方式的多输入输出自由空间光学(multiple input multiple output free space optics,MIMO-FSO)通信系统模型。首先推导了单输入单输出(single input single output,SISO)-PPM系统的误时隙率(slot error rate,SER)计算公式,以此作为参考,在独立同分布和独立分布参数不同情况下,分别推导出MISO-PPM、SIMO-PPM和MIMO-PPM系统的平均SER计算公式,并用数值仿真的方法,分析了它们的平均SER性能。仿真结果表明,在Gamma-Gamma分布模型下,采用多发多收的方法确实能有效提高FSO系统的平均SER性能,如在误时隙率为10-4时,M=2、N=2的MIMO-PPM系统在信道分布参数相同和不同时,与SISO-PPM相比,分别能节省信噪比50dB和65dB左右。实际应用中,M和N分别取3或4就基本足够,对无线光通信系统的理论分析和系统设计具有一定的指导意义。展开更多
为提高多输入多输出(MIMO)电力线通信系统对抗脉冲噪声的能力,基于稀疏贝叶斯学习的理论,利用脉冲噪声在电力线上的相关性,提出了一种消除MIMO电力线脉冲噪声的方案。方案使用全部子载波来联合估计脉冲噪声和可用子载波上的信号,无需训...为提高多输入多输出(MIMO)电力线通信系统对抗脉冲噪声的能力,基于稀疏贝叶斯学习的理论,利用脉冲噪声在电力线上的相关性,提出了一种消除MIMO电力线脉冲噪声的方案。方案使用全部子载波来联合估计脉冲噪声和可用子载波上的信号,无需训练脉冲噪声的统计信息。仿真中脉冲噪声拟合采用Bivariate Middleton Class A模型,结果表明该方案抗脉冲噪声性能比只使用空子载波的多观测向量稀疏贝叶斯学习(MSBL)方案提升了11dB。展开更多
基金supported by the National Basic Research Program of China (973 Program) (2010CB731803)the National Science Foundation for Innovative Research Groups of China (60921001)
文摘The symbol-error-rate（SER） and power allocation for hybrid cooperative（HC） transmission system are investigated.Closed-form SER expression is derived by using the moment generating function（MGF）-based approach.However,the resultant SER contains an MGF of the harmonic mean of two independent random variables（RVs）,which is not tractable in SER analysis.We present a simple MGF expression of the harmonic mean of two independent RVs which avoids the hypergeometric functions used commonly in previous studies.Using the simple MGF,closed-form SER for HC system with M-ary phase shift keying（M-PSK） signals is provided.Further,an approximation as well as an upper bound of the SER is presented.It is shown that the SER approximation is asymptotically tight.Based on the tight SER approximation,the power allocation of the HC system is investigated.It is shown that the optimal power allocation does not depend on the fading parameters of the source-destination（SD） channel and it only depends on the source-relay（SR） and relay-destination（RD） channels.Moreover,the performance gain of the power allocation depends on the ratio of the channel quality between RD and SR.With the increase of this ratio,more performance gain can be acquired.
文摘分析了在Gamma-Gamma分布下基于脉冲位置调制(pulse position modulation,PPM)方式的多输入输出自由空间光学(multiple input multiple output free space optics,MIMO-FSO)通信系统模型。首先推导了单输入单输出(single input single output,SISO)-PPM系统的误时隙率(slot error rate,SER)计算公式,以此作为参考,在独立同分布和独立分布参数不同情况下,分别推导出MISO-PPM、SIMO-PPM和MIMO-PPM系统的平均SER计算公式,并用数值仿真的方法,分析了它们的平均SER性能。仿真结果表明,在Gamma-Gamma分布模型下,采用多发多收的方法确实能有效提高FSO系统的平均SER性能,如在误时隙率为10-4时,M=2、N=2的MIMO-PPM系统在信道分布参数相同和不同时,与SISO-PPM相比,分别能节省信噪比50dB和65dB左右。实际应用中,M和N分别取3或4就基本足够,对无线光通信系统的理论分析和系统设计具有一定的指导意义。
文摘为提高多输入多输出(MIMO)电力线通信系统对抗脉冲噪声的能力,基于稀疏贝叶斯学习的理论,利用脉冲噪声在电力线上的相关性,提出了一种消除MIMO电力线脉冲噪声的方案。方案使用全部子载波来联合估计脉冲噪声和可用子载波上的信号,无需训练脉冲噪声的统计信息。仿真中脉冲噪声拟合采用Bivariate Middleton Class A模型,结果表明该方案抗脉冲噪声性能比只使用空子载波的多观测向量稀疏贝叶斯学习(MSBL)方案提升了11dB。
