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
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
A modified constant modulus algorithm (MCMA) for blind channel equalization is proposed by modifying the constant modulus error function. The MCMA is compared with the conventional constant modulus algorithm (CMA) for...A modified constant modulus algorithm (MCMA) for blind channel equalization is proposed by modifying the constant modulus error function. The MCMA is compared with the conventional constant modulus algorithm (CMA) for symbol-spaced equalization of 4PSK signals. The result shows that the performance of the MCMA is superior to that of the CMA in both convergence rate and intersymbol interference for frequency selective channels in noisy environments. Simulation results using 8PSK signals also demonstrate that a fractionally spaced equalizer can preserve performance over variations in symbol-timing phase, whereas a baud-rate equalizer cannot.展开更多
为克服传统正交小波变换盲均衡算法(Wavelet transform constant modulus blind equalization algorithm,WTCMA)收敛速度慢、均方误差大、易于陷入局部极小值的缺点,提出了一种基于DNA遗传优化的正交小波常模盲均衡算法(Wavelet transfo...为克服传统正交小波变换盲均衡算法(Wavelet transform constant modulus blind equalization algorithm,WTCMA)收敛速度慢、均方误差大、易于陷入局部极小值的缺点,提出了一种基于DNA遗传优化的正交小波常模盲均衡算法(Wavelet transform constant modulus blind equalization algorithm based on the optimization of DNA genetic algorithm,DNA-GA-WTCMA)。该算法采用基于DNA核苷酸链的编码方式表示问题的可能解,并且对编码后的DNA链采用新型的交叉操作和变异操作来寻找DNA种群中的最优个体,然后将得到的最优个体进行解码,把解码后得到的权向量作为均衡器的最优权向量,以避免WTCMA出现局部收敛并提高收敛速度。仿真实验表明,与基于遗传优化的正交小波变换常模盲均衡算法(Wavelet transform constant modulus blind equalization algorithm based on the optimization of genetic algorithm,GA-WTCMA)相比,该算法可以获得更快的收敛速度和更低的均方误差。展开更多
摘要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.
基金Project supported by National Natural Science Foundation of Chi-na(Grant No .60172018)
摘要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:
基金the National Natural Science Foundation of China (60072001)
摘要A modified constant modulus algorithm (MCMA) for blind channel equalization is proposed by modifying the constant modulus error function. The MCMA is compared with the conventional constant modulus algorithm (CMA) for symbol-spaced equalization of 4PSK signals. The result shows that the performance of the MCMA is superior to that of the CMA in both convergence rate and intersymbol interference for frequency selective channels in noisy environments. Simulation results using 8PSK signals also demonstrate that a fractionally spaced equalizer can preserve performance over variations in symbol-timing phase, whereas a baud-rate equalizer cannot.
摘要为克服传统正交小波变换盲均衡算法(Wavelet transform constant modulus blind equalization algorithm,WTCMA)收敛速度慢、均方误差大、易于陷入局部极小值的缺点,提出了一种基于DNA遗传优化的正交小波常模盲均衡算法(Wavelet transform constant modulus blind equalization algorithm based on the optimization of DNA genetic algorithm,DNA-GA-WTCMA)。该算法采用基于DNA核苷酸链的编码方式表示问题的可能解,并且对编码后的DNA链采用新型的交叉操作和变异操作来寻找DNA种群中的最优个体,然后将得到的最优个体进行解码,把解码后得到的权向量作为均衡器的最优权向量,以避免WTCMA出现局部收敛并提高收敛速度。仿真实验表明,与基于遗传优化的正交小波变换常模盲均衡算法(Wavelet transform constant modulus blind equalization algorithm based on the optimization of genetic algorithm,GA-WTCMA)相比,该算法可以获得更快的收敛速度和更低的均方误差。