This paper investigates adaptive blind source separation and equalization for Multiple Input Multiple Output (MIMO) systems. To effectively recover input signals, remove Inter-Symbol Interference (ISI) and suppress In...This paper investigates adaptive blind source separation and equalization for Multiple Input Multiple Output (MIMO) systems. To effectively recover input signals, remove Inter-Symbol Interference (ISI) and suppress Inter-User Interference (IUI), the array input is first transformed into the signal subspace, then with the derived orthogonality between weight vectors of different input signals, a new orthogonal Constant Modulus Algorithm (CMA) is proposed. Computer simulation results illustrate the promising performance of the proposed method. Without channel identification, the proposed method can recover all the system inputs simultaneously and can be adaptive to channel changes without prior knowledge about signals.展开更多
文章从分析MCMA算法的原理出发,研究了其在信道均衡技术上的应用,重点阐述了通过Matlab仿真和Xilinx System Generator for DSP开发软件在FPGA上实现基于MCMA算法的盲均衡器的方法。从硬件协同仿真结果可以看出,实现的盲信道均衡器能够...文章从分析MCMA算法的原理出发,研究了其在信道均衡技术上的应用,重点阐述了通过Matlab仿真和Xilinx System Generator for DSP开发软件在FPGA上实现基于MCMA算法的盲均衡器的方法。从硬件协同仿真结果可以看出,实现的盲信道均衡器能够达到消除码间干扰的效果。展开更多
研究模型选择对支持向量机(SVM)的泛化性能有着重要影响。针对传统梯度算法对初始值敏感及网格搜索法计算复杂的缺点,为了提高全面优化能力和分类精度,提出了一种基于协方差矩阵自适应进化策略(CMA-ES)的支持向量机(SVM)模型优化算法,...研究模型选择对支持向量机(SVM)的泛化性能有着重要影响。针对传统梯度算法对初始值敏感及网格搜索法计算复杂的缺点,为了提高全面优化能力和分类精度,提出了一种基于协方差矩阵自适应进化策略(CMA-ES)的支持向量机(SVM)模型优化算法,通过对SVM泛化性能界(Bounds on Generalization Performance)的优化求解,实现了基于CMA-ES算法的SVM模型选择。在标准数据集上的实验结果表明:相比遗传算法和梯度算法,上述方法能够在较小计算代价下得到更优的超参数,提高支持向量机的预测精度稳定性,尤其适合大样本数据条件下的模型选择。展开更多
This paper presents an improved error function of dithered signed-error constant modulus algorithm （IDSE-CMA） for blind multiuser interference suppression in DS/CDMA systems. It uses a different error function to re...This paper presents an improved error function of dithered signed-error constant modulus algorithm （IDSE-CMA） for blind multiuser interference suppression in DS/CDMA systems. It uses a different error function to replace the former one in sign operation of the DSE-CMA and compares their performance in multiple access interference （MAI） suppression ability. Simulations indicate that the new algorithm has better performance than the similar CMA in terms of convergence speed and steady-state performance：展开更多
This paper investigates the blind algorithm for channel estimation of Orthogonal Frequency Division Multiplexing-Multiple Input Multiple Output (OFDM-MIMO) wireless communication system using the subspace decompositio...This paper investigates the blind algorithm for channel estimation of Orthogonal Frequency Division Multiplexing-Multiple Input Multiple Output (OFDM-MIMO) wireless communication system using the subspace decomposition of the channel received complex baseband signals and proposes a new two-stage blind algorithm. Exploited the second-order cyclostationarity inherent in OFDM with cyclic prefix and the characteristics of the phased antenna, the practical HIPERLAN/2 standard based OFDM-MIMO simulator is established with the sufficient consideration of statistical correlations between the multiple antenna channels under wireless wideband multipath fading environment, and a new two-stage blind algorithm is formulated using rank reduced subspace channel matrix approximation and adaptive Constant Modulus (CM)criterion. Simulation results confirm the theoretical analysis and illustrate that the proposed algorithm is capable of tracking matrix channel variations with fast convergence rate and improving acceptable overall system performance over various common wireless and mobile communication links.展开更多
This paper aims to develop an approach to investigating the effect of a particular parameter on the output accuracy of transformer thermal models,i.e.sensitivity analysis,which can not only reveal the most sensitive p...This paper aims to develop an approach to investigating the effect of a particular parameter on the output accuracy of transformer thermal models,i.e.sensitivity analysis,which can not only reveal the most sensitive parameter of a thermal model but also improve model output accuracies.For the first time,the nonlinear time constant(NTC)of transformer oil is proposed to reshape three practical top-oil temperature models based on an expression of nonlinear thermal conductance:the modified IEEE clause 7 model,Swift’s model,and Susa’s model.Then,the multi-parametric sensitivity analysis(MPSA)is undertaken to reveal the effect of each parameter on the model output accuracy.Through onsite data validation,the results show that the accuracy performance of the proposed NTC thermal models are improved significantly by considering the nonlinear effect of oil time constant.Moreover,the derived sensitivity performances can clearly reveal the most dominant parameter of the model,so as to simplify the model parameter identification process by reducing the number of insensitive parameters.Finally,the heat-run test data is used as a reference to validate parameters optimized through a genetic algorithm(GA),which demonstrates that the proposed NTC IEEE model has not only one sensitive parameter but also superior accuracy performance.展开更多
由于定风量空调机组(Constant Air Volume Air Handling Unit, CAVAHU)输出的新风量往往是固定的,当空调房间内的额定人员数量超员或不足时,会导致空调房间CO_(2)浓度测量值Cn高于室内CO_(2)浓度设定值Cn=Cn,set或新风负荷增大的状况。...由于定风量空调机组(Constant Air Volume Air Handling Unit, CAVAHU)输出的新风量往往是固定的,当空调房间内的额定人员数量超员或不足时,会导致空调房间CO_(2)浓度测量值Cn高于室内CO_(2)浓度设定值Cn=Cn,set或新风负荷增大的状况。对此提出了一种空调房间CO_(2)浓度二自由度内模分数阶PI控制策略和设计改进多目标人工蜂群算法(Improved Multi-Objective Artificial Bee Colony Algorithm, IMOABCA)对控制器参数实施整定的思路。首先,基于人工蜂群算法,分别对雇佣蜂和观察蜂引入自适应惯性权重和精英组策略,进行非线性递减和柯西变异的演变,并结合观察蜂搜索特性,将最小粒子角度引入外部档案集,获取相应的Pareto解集,设计IMOABCA,进而对控制器的3个参数进行整定,获得相应的最优值。最后,借助MATLAB工具,对该室内CO_(2)浓度的二自由度内模分数阶PI控制系统进行组态和仿真。结果表明:该室内CO_(2)浓度二自由度内模分数阶PI控制系统和IMOABCA是可行的,能够实现Cn=Cn,set的调节目的和获取控制器的3个参数最优值,提升室内CO_(2)浓度的调节品质。展开更多
文摘This paper investigates adaptive blind source separation and equalization for Multiple Input Multiple Output (MIMO) systems. To effectively recover input signals, remove Inter-Symbol Interference (ISI) and suppress Inter-User Interference (IUI), the array input is first transformed into the signal subspace, then with the derived orthogonality between weight vectors of different input signals, a new orthogonal Constant Modulus Algorithm (CMA) is proposed. Computer simulation results illustrate the promising performance of the proposed method. Without channel identification, the proposed method can recover all the system inputs simultaneously and can be adaptive to channel changes without prior knowledge about signals.
文摘研究模型选择对支持向量机(SVM)的泛化性能有着重要影响。针对传统梯度算法对初始值敏感及网格搜索法计算复杂的缺点,为了提高全面优化能力和分类精度,提出了一种基于协方差矩阵自适应进化策略(CMA-ES)的支持向量机(SVM)模型优化算法,通过对SVM泛化性能界(Bounds on Generalization Performance)的优化求解,实现了基于CMA-ES算法的SVM模型选择。在标准数据集上的实验结果表明:相比遗传算法和梯度算法,上述方法能够在较小计算代价下得到更优的超参数,提高支持向量机的预测精度稳定性,尤其适合大样本数据条件下的模型选择。
基金Project supported by National Natural Science Foundation of Chi-na(Grant No .60172018)
文摘This paper presents an improved error function of dithered signed-error constant modulus algorithm （IDSE-CMA） for blind multiuser interference suppression in DS/CDMA systems. It uses a different error function to replace the former one in sign operation of the DSE-CMA and compares their performance in multiple access interference （MAI） suppression ability. Simulations indicate that the new algorithm has better performance than the similar CMA in terms of convergence speed and steady-state performance：
文摘This paper investigates the blind algorithm for channel estimation of Orthogonal Frequency Division Multiplexing-Multiple Input Multiple Output (OFDM-MIMO) wireless communication system using the subspace decomposition of the channel received complex baseband signals and proposes a new two-stage blind algorithm. Exploited the second-order cyclostationarity inherent in OFDM with cyclic prefix and the characteristics of the phased antenna, the practical HIPERLAN/2 standard based OFDM-MIMO simulator is established with the sufficient consideration of statistical correlations between the multiple antenna channels under wireless wideband multipath fading environment, and a new two-stage blind algorithm is formulated using rank reduced subspace channel matrix approximation and adaptive Constant Modulus (CM)criterion. Simulation results confirm the theoretical analysis and illustrate that the proposed algorithm is capable of tracking matrix channel variations with fast convergence rate and improving acceptable overall system performance over various common wireless and mobile communication links.
基金supported in part by the National Key R&D Program of China under Grant No.2018YFE0208400in part by Science and Technology Project of Guangdong Power Grid Company under Grant No.031900KK52180153.
文摘This paper aims to develop an approach to investigating the effect of a particular parameter on the output accuracy of transformer thermal models,i.e.sensitivity analysis,which can not only reveal the most sensitive parameter of a thermal model but also improve model output accuracies.For the first time,the nonlinear time constant(NTC)of transformer oil is proposed to reshape three practical top-oil temperature models based on an expression of nonlinear thermal conductance:the modified IEEE clause 7 model,Swift’s model,and Susa’s model.Then,the multi-parametric sensitivity analysis(MPSA)is undertaken to reveal the effect of each parameter on the model output accuracy.Through onsite data validation,the results show that the accuracy performance of the proposed NTC thermal models are improved significantly by considering the nonlinear effect of oil time constant.Moreover,the derived sensitivity performances can clearly reveal the most dominant parameter of the model,so as to simplify the model parameter identification process by reducing the number of insensitive parameters.Finally,the heat-run test data is used as a reference to validate parameters optimized through a genetic algorithm(GA),which demonstrates that the proposed NTC IEEE model has not only one sensitive parameter but also superior accuracy performance.
文摘由于定风量空调机组(Constant Air Volume Air Handling Unit, CAVAHU)输出的新风量往往是固定的,当空调房间内的额定人员数量超员或不足时,会导致空调房间CO_(2)浓度测量值Cn高于室内CO_(2)浓度设定值Cn=Cn,set或新风负荷增大的状况。对此提出了一种空调房间CO_(2)浓度二自由度内模分数阶PI控制策略和设计改进多目标人工蜂群算法(Improved Multi-Objective Artificial Bee Colony Algorithm, IMOABCA)对控制器参数实施整定的思路。首先,基于人工蜂群算法,分别对雇佣蜂和观察蜂引入自适应惯性权重和精英组策略,进行非线性递减和柯西变异的演变,并结合观察蜂搜索特性,将最小粒子角度引入外部档案集,获取相应的Pareto解集,设计IMOABCA,进而对控制器的3个参数进行整定,获得相应的最优值。最后,借助MATLAB工具,对该室内CO_(2)浓度的二自由度内模分数阶PI控制系统进行组态和仿真。结果表明:该室内CO_(2)浓度二自由度内模分数阶PI控制系统和IMOABCA是可行的,能够实现Cn=Cn,set的调节目的和获取控制器的3个参数最优值,提升室内CO_(2)浓度的调节品质。
