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排序方式: 共有194条查询结果,搜索用时 218 毫秒
31.
The minimum mean square error (MMSE) detection method involved matrix inversion operation with excessive computational burden. In this paper, we develop an improved quantum linear system algorithm to solve matrix inversion problem of the MMSE detection method in uplink massive multiple-input and multiple-output (MIMO) systems. In order to apply reasonably the robust computational power of quantum computing, we optimize the preparation of the input state and the extraction of the solution from the final entangled quantum state. We prove that this algorithm can reduce computational complexity to . 相似文献
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In this paper, the downlink of cell-free massive multiple-input multiple-output (MIMO) with zero-forcing processing is considered. To maximize the system energy efficiency (EE), we design power allocation algorithms taking into account imperfect channel state information, hardware, and backhaul power consumption. The total EE optimization problem is nonconvex, which traditionally is solved by the successive convex approximation framework which involves second order cone programs (SOCPs). As such methods have high complexity, the run time is extremely long, especially in large-scale systems with thousands of access points (APs) and users. To overcome this problem, in this paper, we propose to apply two computationally efficient methods, namely proximal gradient (PG) method and accelerated proximal gradient (APG) method to solve the considered problem. Numerical results show that, compared to the conventional SOCPs approximation methods, our proposed methods achieve the same performance while the run time is much smaller. 相似文献
33.
In this paper, we introduce a mixed- analog-to-digital converter (ADC) architecture for massive multiple-input multiple-output (MIMO) systems and study the system’s performance mainly includes the achievable spectral efficiency and energy efficiency. In principle, the mixed-ADC architecture permits the one part of antennas at the base station (BS) are connected to speed and expensive full-resolution ADCs and the remaining part of the antennas are connected to the cheap low-resolution ADCs. By applying the general maximum-ratio combining detector, a tractable approximate expression for the achievable SE is obtained. Leveraging on the derived results, the effects of the number of BS antennas and the percent of the full-resolution ADCs on the achievable SE are investigated. Results show that the achievable SE increases with the percent of the full-resolution ADCs and the number of BS antennas. Based on a realistic power consumption model, we evaluate the energy efficiency for the considered mixed-ADC architecture. Moreover, under the certain achievable SE constraint, we maximize the energy efficiency by adjusting the number of low-resolution ADCs and the resolution bits of the corresponding ADC device. Numerical results showcase that the energy efficiency can be improved by enhancing the average transmitted power, and there exists an optimal number of resolution bits and the number of antennas to maximize the energy efficiency, which indicates that the application of mixed-ADC architecture has a great potential in future mobile communication system. 相似文献
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三轴液压仿真转台本质上是非线性变参数多输入多输出系统.系统负载、油源压力、增益的变化及耦合作用随速度,加速度的变化造成很大的参数不确定性.针对液压转台提出一种基于SIMULINK模型线性化的多输入多输出非线性定量反馈设计方法.其本质是找到液压伺服系统一系列控制特性最差的运行点,直接用它们的频率响应集合来综合非线性定量反馈控制器.这种方法简化了目前的QFT多输入多输出控制系统设计方法,显示了很大的优越性.文中举例说明这种方法的效果. 相似文献
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Based on an existing three-dimensional (3-D) channel model developed by WINNER II/+, we propose an extended 3-D channel model, which takes the vertical velocity component and polarized array structure into account. The distributions of several channel parameters are verified through simulation. Furthermore, initial system-level simulation results for a 3D-MIMO transmission scheme are presented in this paper. 相似文献
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陈文德 《应用数学学报(英文版)》1996,12(1):102-108
CHENWENDE(陈文德)(InstituteofSystemsSciences,theChineseAcademyofSciences,Beijing100080,ChinaandStateKeyLabraryofInformationSecur... 相似文献
39.
第一讲进入21世纪的声纳技术 总被引:3,自引:0,他引:3
海洋开发和反潜战的需求是推动声纳技术开发的巨大动力.水声物理、水声信号处理及相关学科的发展又促使声纳设计日趋完善.文章介绍了声纳技术在进入21世纪时所面临的机遇和挑战,水声信号处理领域近期研究的热点问题以及声纳系统设计中的技术创新课题. 相似文献
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