共查询到19条相似文献,搜索用时 144 毫秒
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给出了一种天线阵列信号的预处理方法,并将线性受限条件和判决反馈用于最小二乘,提出了一种基于天线阵列的预处理线性受限判决反馈最小二乘恒模多用户检测算法,称为PLC-DFB-LSCMA算法,并与判决反馈最小二乘恒模算法(DFB-LSCMA)及传统的最小二乘恒模算法(LSCMA)进行了仿真比较,仿真结果表明,PLC-DFB-LSCMA算法的信干比性能及误码性能仍优于后二者。 相似文献
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线性受限最小二乘恒模盲多用户检测算法 总被引:4,自引:0,他引:4
本文将线性受限条件运用于最小二乘恒模算法,提出了一种线性受限最小二乘恒模盲多用户检测算法,称为LCLSCMA,并将它与传统的最小二乘恒模算法(LSCMA)进行了仿真比较。仿真结果表明,本文提出的LCLSCMA算法比传统的最小二乘恒模算法的信干比性能和误码率性能要好,特别在低信噪比强多址干扰情况下性能仍优于LSCMA。 相似文献
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基于最小二乘恒模算法及子空间方法的盲多用户检测算法 总被引:11,自引:0,他引:11
恒模算法(CMA)是一种广泛应用于阵列处理、均衡、多用户检测中的盲算法。最小二乘恒模算法(LSCMA)由于其全局收敛性及稳定性受到关注,但是它在信噪比较低时性能不是很理想。本文将最小二乘恒模算法与子空间方法相结合,提出一种基于子空间分解的恒模算法,称为LSCM_SUB算法。仿真结果表明这种算法的收敛性能比LSCMA要好,尤其是在信噪比低的时候。 相似文献
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介绍一种用于阵列天线,利用信号恒模特性进行自适应波束形成的算法,即最小二乘恒模算法。它通过对阵列天线单元接收信号进行非线性处理,在保持期望目标信号的同时,可在多个干扰方向形成零陷,从而大幅度提高信干噪比(SINR)。文章通过对该算法的仿真对其性能进行了分析,最后阐述了基于该算法的阵列天线应用。 相似文献
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本文提出了MC-CDMA系统中一种预处理线性受限最小二乘恒模多用户检测算法(Pre-processed Linearly Con- strained Least Squares Constant Modulus Multi-user detection Algorithm),称为P-LCLSCMA。它是对MC-CDMA接收信号进行预处理,即在每次迭代中,用已估信道参数先消除信道在各个子载波上对期望用户信号的影响,然后对处理后的信号用P- LCLSCMA算法进行多用户检测,从而确保了算法收敛于期望信号,提高了系统的检测性能。我们对这种新算法分别在下行链路和上行链路进行了仿真,仿真结果表明,本文提出的P-LCLSCMA算法的误码率和信干比性能得到了提高。 相似文献
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该文提出一种基于预处理递归最小二乘恒模算法(PP-RLSCMA)的多径异步CDMA系统盲自适应接收技术。首先对接收信号进行自适应预处理,并分析了预处理器的复杂性和稳定性。预处理的目的是通过对干扰和噪声的部分抑制以提高恒模接收的性能,所提出的预处理方法只与多径信道的最大长度有关。鉴于统计恒模算法收敛速度慢的缺点,提出一种快速递归最小二乘恒模算法的盲自适应接收。仿真表明,该文算法的误码率及收敛性能比LCMMV,LCCMA好。 相似文献
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The performance of adaptive antenna arrays in the presence of weak interfering signals (below thermal noise) is studied. It is shown that conventional adaptive antenna arrays sample matrix inversion (SMI) algorithm is used are unable to suppress such interfering signals. To overcome this problem, the SMI algorithm is modified. In the modified algorithm, the covariance matrix is redefined such that the effect of thermal noise on the weights of adaptive arrays is reduced. Thus, the weights are dictated by relatively weak signals. It is shown that the modified algorithm provides the desired interference protection. 相似文献
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在多天线信号联合检测场景中,信号存在相关性和噪声方差无法准确确定问题会同时发生,导致经典的多天线能量检测算法性能不理想。为此,提出一种基于多天线信号等增益合成的信号盲检测算法。该算法通过多天线合成技术,补偿各路天线接收信号的差异性,然后进行等增益合成,并取合成信号能量与单路天线信号的能量比值作为检测统计量,利用统计理论推导出相应的检测门限和检测概率。仿真结果表明,新算法能够摆脱噪声的不确定性影响,且比现有盲检测算法具有更优的检测性能。 相似文献
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Won Hyung Ryu Min Kyu Park Seong Keun Oh 《Communications, IEEE Transactions on》2002,50(8):1337-1347
We propose parallel and serial code-acquisition schemes using antenna arrays for initial acquisition of direct-sequence spread-spectrum signals, which can lower substantially the range of detectable signal-to-noise ratio (SNR) as compared to the corresponding conventional schemes with a single antenna. The proposed schemes use the sum of all the single-antenna decision samples from antenna arrays, corresponding to an identical subsequence of a given pseudonoise code as a decision variable in order to enhance SNR of the resulting signal. We analyze the mean acquisition time performance under an additive white Gaussian noise channel and spatially correlated time-varying flat Rayleigh fading channels by deriving the expressions for the probabilities of detection, missing, and false alarm. We consider two extreme cases of spatial fading correlation among antenna arrays, the case of uncorrelated diversity antennas and the case of perfectly correlated antennas. From numerical results, we see that the acquisition performance of the proposed schemes using antenna arrays becomes improved continually as the number of antennas increases and the performance improvement depends on the degree of spatial fading correlation. 相似文献
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Massa A. Donelli M. De Natale F.G.B. Caorsi S. Lommi A. 《Antennas and Propagation, IEEE Transactions on》2004,52(11):2919-2924
Planar arrays are successfully employed in radar and communication systems in order to allow three-dimensional-scanning. In the framework of real-time control of antenna arrays, starting from the Applebaum theory, this paper presents an approach based on a customized genetic algorithm aimed at adaptively eliminating interfering signals. Successful applications are presented in order to evaluate the effectiveness of the proposed approach in term of performances and computational complexity. 相似文献
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提出了一种基于阵列天线的卫星导航欺骗干扰检测与抑制方法。利用真实卫星导航信号从上半球空间多个方向入射到阵列天线而欺骗干扰信号则是从同一方向入射到阵列天线的差异性进行干扰检测判决。首先,对阵列天线每个阵元单元通道接收信号进行多颗卫星并行解扩从处理;其次,利用解扩后的阵列数据对每颗卫星进行方位估计;再次,根据估计卫星来向数据的一致性进行干扰检测判决;最后,在判决存在欺骗干扰时利用欺骗干扰的方向信息重构协方差矩阵,采用自适应调零算法对欺骗干扰进行抑制。通过计算机仿真试验对所提方法的正确性和有效性进行了验证。 相似文献