eess.SP - 2023-10-15

Distributed Estimation with Partially Accessible Information: An IMAT Approach to LMS Diffusion

  • paper_url: http://arxiv.org/abs/2310.09970
  • repo_url: None
  • paper_authors: Mahdi Shamsi, Farokh Marvasti
  • for: 提高分布式算法的可见性和稳定性
  • methods: 基于信号流分析的组合策略分析框架和阈值算法
  • results: 在时域和变换域中存在缺失信息的情况下,提出了一种基于阈值算法的支持向量识别和利用策略,并在两种组合enario中进行了示范
    Abstract Distributed algorithms, particularly Diffusion Least Mean Square, are widely favored for their reliability, robustness, and fast convergence in various industries. However, limited observability of the target can compromise the integrity of the algorithm. To address this issue, this paper proposes a framework for analyzing combination strategies by drawing inspiration from signal flow analysis. A thresholding-based algorithm is also presented to identify and utilize the support vector in scenarios with missing information about the target vector's support. The proposed approach is demonstrated in two combination scenarios, showcasing the effectiveness of the algorithm in situations characterized by sparse observations in the time and transform domains.
    摘要 diffused least squares 算法在各个领域得到广泛应用,特别是因为它们的可靠性、鲁棒性和快速收敛性。然而,target vector的有限可见性可能会导致算法的完整性受到损害。为解决这个问题,本文提出了一种基于信号流分析的框架,并提出了一种阈值分析法来Identify和利用目标向量的支持向量在有限信息的情况下。该方法在时域和变换域中的缺失观测场景中进行了两种组合场景的示例,展示了该算法在稀疏观测场景中的效果。Note: "Diffusion Least Mean Square" in the original text is translated as "diffused least squares 算法" in Simplified Chinese, as "diffusion" is not a commonly used term in Chinese and "least squares" is more commonly used to refer to this type of algorithm.

Semi-Supervised End-to-End Learning for Integrated Sensing and Communications

  • paper_url: http://arxiv.org/abs/2310.09940
  • repo_url: https://github.com/josemateosramos/sslisac
  • paper_authors: José Miguel Mateos-Ramos, Baptiste Chatelier, Christian Häger, Musa Furkan Keskin, Luc Le Magoarou, Henk Wymeersch
  • for: 本文针对 ISAC 混合感知通信系统的问题进行研究,旨在提高硬件、频率和能源效率。
  • methods: 本文使用 differentiable model-based 学习方法,实现了单目标检测和定位估计,以及多input single-output 通信。
  • results: 我们的结果显示,使用半指导学习策略可以实现相似的性能,仅需使用 98.8% fewer labeled data。
    Abstract Integrated sensing and communications (ISAC) is envisioned as one of the key enablers of next-generation wireless systems, offering improved hardware, spectral, and energy efficiencies. In this paper, we consider an ISAC transceiver with an impaired uniform linear array that performs single-target detection and position estimation, and multiple-input single-output communications. A differentiable model-based learning approach is considered, which optimizes both the transmitter and the sensing receiver in an end-to-end manner. An unsupervised loss function that enables impairment compensation without the need for labeled data is proposed. Semi-supervised learning strategies are also proposed, which use a combination of small amounts of labeled data and unlabeled data. Our results show that semi-supervised learning can achieve similar performance to supervised learning with 98.8% less required labeled data.
    摘要 “集成感测通信(ISAC)是未来无线系统的关键促进因素,提供了改善硬件、频率和能量效率。本文考虑了一种受损均匀线列天线的ISAC收发器,实现单目标探测和位置估计,以及多输入单出口通信。我们使用可导模型基本学习方法,在终端干扰下优化发射器和探测Receiver。我们提出了无标签数据补偿的不监督学习策略,以及使用小量标签数据和无标签数据的半监督学习策略。我们的结果表明,半监督学习可以与监督学习准确率相似,仅需98.8%的标签数据。”Note: The translation is in Simplified Chinese, which is the standard form of Chinese used in mainland China and Singapore. If you need Traditional Chinese, please let me know.

Enhance Security of Time-Modulated Array-Enabled Directional Modulation by Introducing Symbol Ambiguity

  • paper_url: http://arxiv.org/abs/2310.09922
  • repo_url: None
  • paper_authors: Zhihao Tao, Zhaoyi Xu, Athina Petropulu
  • for: 这个论文研究了时间模拟数组(TMA)启用的方向性模拟(DM)通信系统是否可以破解。
  • methods: 论文首先示出了使用格点搜索可以成功找到TMA生成的唯一和实际混合矩阵。然后,提出了引入符号模糊来防止格点搜索的推论,并设计了两个原则来构建符号模糊:一是缺rank的缺失和非唯一性的ON-OFF切换模式。
  • results: 论文提出的原则和机制不仅可以在理论上设计更安全的TMA DM系统,还经验 validate 了其效果。
    Abstract In this paper, if the time-modulated array (TMA)-enabled directional modulation (DM) communication system can be cracked is investigated and the answer is YES! We first demonstrate that the scrambling data received at the eavesdropper can be defied by using grid search to successfully find the only and actual mixing matrix generated by TMA. Then, we propose introducing symbol ambiguity to TMA to defend the defying of grid search, and design two principles for the TMA mixing matrix, i.e., rank deficiency and non-uniqueness of the ON-OFF switching pattern, that can be used to construct the symbol ambiguity. Also, we present a feasible mechanism to implement these two principles. Our proposed principles and mechanism not only shed light on how to design a more secure TMA DM system theoretically in the future, but also have been validated to be effective by bit error rate measurements.
    摘要 在这篇论文中,我们调查了使用时间模拟数组(TMA)启用方向性模式(DM)通信系统是否可以被破解。我们首先表明了使用格点搜索可以成功地找到由TMA生成的唯一和实际混合矩阵。然后,我们提议引入符号模糊性来防止格点搜索的推断,并设计了两种原则来构建符号模糊性,即缺陷行列和非唯一性的ON-OFF切换模式。此外,我们还提出了可行的实现机制。我们的提出的原则和机制不仅帮助我们在未来理论上设计更安全的TMA DM系统,而且已经被验证了通过比特错误率测量。

Stacked Intelligent Metasurface Performs a 2D DFT in the Wave Domain for DOA Estimation

  • paper_url: http://arxiv.org/abs/2310.09861
  • repo_url: None
  • paper_authors: Jiancheng An, Chau Yuen, Marco Di Renzo, Merouane Debbah, H. Vincent Poor, Lajos Hanzo
  • for: 这个论文的目的是提出一种基于受托辐射元件(SIM)的技术来实现二维方向来源估算(DOA)。
  • methods: 这种技术使用了一种先进的SIM,其中每个元件在入射波传播过程中自动完成了二维离散傅里叶变换(DFT)。为了使SIM完成这个任务,我们设计了一个梯度下降算法,用于逐步更新每个元件的相位Shift,以最小化SIM的响应和2D DFT矩阵之间的差异。
  • results: 数值模拟结果表明,一个充分训练的SIM可以很准确地完成2D DFT。例如,在实验中,SIM的计算速度为光学计算速度,DOA估算的 сред平均误差(MSE)为10^-4。
    Abstract Staked intelligent metasurface (SIM) based techniques are developed to perform two-dimensional (2D) direction-of-arrival (DOA) estimation. In contrast to the conventional designs, an advanced SIM in front of the receiving array automatically performs the 2D discrete Fourier transform (DFT) as the incident waves propagate through it. To arrange for the SIM to carry out this task, we design a gradient descent algorithm for iteratively updating the phase shift of each meta-atom in the SIM to minimize the fitting error between the SIM's response and the 2D DFT matrix. To further improve the DOA estimation accuracy, we configure the phase shifts in the input layer of SIM to generate a set of 2D DFT matrices having orthogonal spatial frequency bins. Extensive numerical simulations verify the capability of a well-trained SIM to perform 2D DFT. Specifically, it is demonstrated that the SIM having an optical computational speed achieves an MSE of $10^{-4}$ in 2D DOA estimation.
    摘要 “基于固化智能表面(SIM)技术的二维方向来源估计(2D DOA)方法已经开发出来。与传统设计不同的是,我们在接收阵列前方的高级SIM上自动执行2D离散傅里叶变换(DFT)。为让SIM进行这项任务,我们设计了一种梯度下降算法,通过迭代更新每个元素的相位偏移,以最小化SIM的响应和2D DFT矩阵之间的差异。为了进一步提高DOA估计精度,我们在SIM的输入层中配置了一系列的2D DFT矩阵,其中每个矩阵具有正交的空间频率分辨率。数值仿真表明,一个具有光学计算速度的SIM可以实现2D DOA估计的 mean squared error(MSE)为10^-4。”Note: The translation is in Simplified Chinese, which is one of the two standard forms of Chinese writing. The other form is Traditional Chinese.

Towards Structural Sparse Precoding: Dynamic Time, Frequency, Space, and Power Multistage Resource Programming

  • paper_url: http://arxiv.org/abs/2310.09840
  • repo_url: None
  • paper_authors: Zhongxiang Wei, Ping Wang, Qingjiang Shi, Xu Zhu, Christos Masouros
  • for: 这篇论文主要针对 fifth-generation 通信系统中的即时传输应用需求,尤其是在时间维度上的质量要求。
  • methods: 本论文使用 multistage 优化方法,包括时间、频率、空间和能量领域资源的共同优化。
  • results: 本论文的设计可以实现高性能的传输系统,并且具有快速的数据测试速率。
    Abstract In last decades, dynamic resource programming in partial resource domains has been extensively investigated for single time slot optimizations. However, with the emerging real-time media applications in fifth-generation communications, their new quality of service requirements are often measured in temporal dimension. This requires multistage optimization for full resource domain dynamic programming. Taking experience rate as a typical temporal multistage metric, we jointly optimize time, frequency, space and power domains resource for multistage optimization. To strike a good tradeoff between system performance and computational complexity, we first transform the formulated mixed integer non-linear constraints into equivalent convex second order cone constraints, by exploiting the coupling effect among the resources. Leveraging the concept of structural sparsity, the objective of max-min experience rate is given as a weighted 1-norm term associated with the precoding matrix. Finally, a low-complexity iterative algorithm is proposed for full resource domain programming, aided by another simple conic optimization for obtaining its feasible initial result. Simulation verifies that our design significantly outperform the benchmarks while maintaining a fast convergence rate, shedding light on full domain dynamic resource programming of multistage optimizations.
    摘要 最近几十年,在半资源领域中进行了广泛的动态资源编程,以优化单个时间槽。然而,五代通信技术出现后,新的服务质量要求 oft measure在时间维度上。这需要进行全资源领域的多阶段优化。以经验率为例的 temporaldimensional metric,我们同时优化了时间、频率、空间和功率领域的资源。为了 достичь系统性能和计算复杂度之间的好 equilibrio,我们首先将混合整数非线性约束转化为等效的几何二次辐射约束,利用资源之间的协同作用。然后,我们给出了一个优化目标函数,其中包含了约束matrix的权重的1- norm。最后,我们提出了一种低复杂度的迭代算法,用于实现全资源领域的动态资源编程,并且使用另一个简单的几何优化算法来获得其可行的初始结果。实验证明了我们的设计在比较性能和速度方面具有显著的优势,提供了全资源领域的动态资源编程的全面性和可行性。

Cell-Free Massive MIMO Surveillance Systems

  • paper_url: http://arxiv.org/abs/2310.09769
  • repo_url: None
  • paper_authors: Zahra Mobini, Hien Quoc Ngo, Michail Matthaiou, Lajos Hanzo
  • for: 本研究旨在提高国家安全性,通过使用无线监测系统来监测不可信通信链接。
  • methods: 本研究提出了一种新的维度免疫多输入多输出(CF-mMIMO)无线监测系统,其中许多分散的多天线帮助监测节点(MNs)进行观察或干扰不可信的通信链接。
  • results: 我们分析了CF-mMIMO无线监测系统的性能,并 deriv了关于监测成功率的关闭式表达式。我们还提出了一种满足同时观察和干扰的模式分配算法,以及一种最大化最小监测成功率的干扰发射功率分配算法。研究结果表明,我们的提posed CF-mMIMO系统可以在相对较少的MN数量下提供显著性能提升,比基准值co-located mMIMO系统的11倍。
    Abstract Wireless surveillance, in which untrusted communications links are proactively monitored by legitimate agencies, has started to garner a lot of interest for enhancing the national security. In this paper, we propose a new cell-free massive multiple-input multiple-output (CF-mMIMO) wireless surveillance system, where a large number of distributed multi-antenna aided legitimate monitoring nodes (MNs) embark on either observing or jamming untrusted communication links. To facilitate concurrent observing and jamming, a subset of the MNs is selected for monitoring the untrusted transmitters (UTs), while the remaining MNs are selected for jamming the untrusted receivers (URs). We analyze the performance of CF-mMIMO wireless surveillance and derive a closed-form expression for the monitoring success probability of MNs. We then propose a greedy algorithm for the observing vs, jamming mode assignment of MNs, followed by the conception of a jamming transmit power allocation algorithm for maximizing the minimum monitoring success probability concerning all the UT and UR pairs based on the associated long-term channel state information knowledge. In conclusion, our proposed CF-mMIMO system is capable of significantly improving the performance of the MNs compared to that of the state-of-the-art baseline. In scenarios of a mediocre number of MNs, our proposed scheme provides an 11-fold improvement in the minimum monitoring success probability compared to its co-located mMIMO benchmarker.
    摘要 无线监测,在无法确保通信链路的情况下,由合法机构监测,已经吸引了很多关注,以提高国家安全。在这篇论文中,我们提议一种新的终端分布式多输入多输出(CF-mMIMO)无线监测系统,其中一大量分布在多个antenna帮助合法监测节点(MNs)进行观察或干扰不可信通信链路。为实现同时观察和干扰,一部分MNs用于观察不可信发送器(UTs),而另一部分MNs用于干扰不可信接收器(URs)。我们分析了CF-mMIMO无线监测系统的性能,并 derivated一个关闭式表达式来表示MNs的监测成功率。然后,我们提出了一种满足策略来选择MNs的观察和干扰模式,并提出了一种基于长期通道状态信息的干扰发射功率分配策略,以最大化所有UT和UR对的监测成功率。在结论中,我们的提议的CF-mMIMO系统可以在MNs的数量不多的情况下,与当前基准相比,提高监测成功率的最小值。在一些中等数量的MNs情况下,我们的方案提供了11倍的监测成功率提升,相比于其相对位置的mMIMO参考。

Assessing Smart Algorithms for Gait Phases Detection in Lower Limb Prosthesis: A Comprehensive Review

  • paper_url: http://arxiv.org/abs/2310.09735
  • repo_url: None
  • paper_authors: Barath Kumar JK, Aswadh Khumar G S
  • for: 这些研究旨在提高步态分类的精度,以便在脊梁rehabilitation系统中应用。
  • methods: 这些研究使用了多种感知器,包括佩戴式和非佩戴式的感知器,以获取步态数据。
  • results: 研究发现了多种感知器和感知器组合,可以在日常环境中分析步态模式。这些感知器的选择因素包括感知器的精度、可靠性和成本等。
    Abstract Over the past few years, the division of gait phases has emerged as a complex area of research that carries significant importance for various applications in the field of gait technologies. The accurate partitioning of gait phases plays a crucial role in advancing these applications. Researchers have been exploring a range of sensors that can be employed to provide data for algorithms involved in gait phase partitioning. These sensors can be broadly categorized into two types: wearable and non-wearable, each offering unique advantages and capabilities. In our study aimed at examining the current approaches to gait analysis and detection specifically designed for implementation in ambulatory rehabilitation systems, we conducted a comprehensive meta-analysis of existing research studies. Our analysis revealed a diverse range of sensors and sensor combinations that demonstrate the ability to analyze gait patterns in ambulatory settings. These sensor options vary from basic force-based binary switches to more intricate setups incorporating multiple inertial sensors and sophisticated algorithms. The findings highlight the wide spectrum of available technologies and methodologies used in gait analysis for ambulatory applications. To conduct an extensive review, we systematically examined two prominent databases, IEEE and Scopus, with the aim of identifying relevant studies pertaining to gait analysis. The search criteria were limited to 189 papers published between 1999 and 2023. From this pool, we identified and included five papers that specifically focused on various techniques including Thresholding, Quasi-static method, adaptive classifier, and SVM-based approaches. These selected papers provided valuable insights for our review.
    摘要 过去几年,走势阶段的分类已经成为一个复杂的研究领域,具有重要的应用意义在走势技术领域。精确地分类走势阶段是提高这些应用的关键因素。研究人员正在探索一种以下的仪器来提供资料 для走势阶段分类的算法:抽象和非抽象的仪器,每一种都有各自的优点和能力。在我们的研究中,我们对于数位训练系统中的走势分析和检测进行了广泛的meta分析。我们发现了一些不同的仪器和仪器组合,可以在行动 Setting中分析走势模式。这些仪器选择自基本的力矩基于的二进制变数到更复杂的设备和复杂的算法。我们的发现显示了走势分析在行动应用中的广泛技术和方法。为了进行广泛的评审,我们对IEEE和Scopus两个著名的数据库进行了系统性的搜寻,并将搜寻结果限定为1999年至2023年发表的189篇文献。从这个池中,我们选择和包括了不同的技术,例如阈值分类、静止方法、适应分类和SVM基本方法的五篇文献。这些选择的文献给我们提供了宝贵的启示。

A generalization of the achievable rate of a MISO system using Bode-Fano wideband matching theory

  • paper_url: http://arxiv.org/abs/2310.09723
  • repo_url: None
  • paper_authors: Nitish Deshpande, Miguel R. Castellanos, Saeed R. Khosravirad, Jinfeng Du, Harish Viswanathan, Robert W. Heath Jr
  • for: 本研究旨在提高多输入单输出(MISO)系统的信息理论可实现率,并具体实现了宽频匹配理论。
  • methods: 本研究使用多口电路理论方法,具体是利用频率选择性的散射参数来优化MISO系统的可实现率。
  • results: 研究结果表明,使用优化的传输系数和劳达-法诺不等式约束,可以提高MISO系统的信息理论可实现率。对比 идеаль的可实现率、不考虑匹配约束的可实现率以及使用不优化匹配策略的可实现率,研究结果表明优化匹配网络可以提高MISO系统的可实现率。此外,研究还提出了一种实用的方法来估算可实现率上限。
    Abstract Impedance-matching networks affect power transfer from the radio frequency (RF) chains to the antennas. Their design impacts the signal to noise ratio (SNR) and the achievable rate. In this paper, we maximize the information-theoretic achievable rate of a multiple-input-single-output (MISO) system with wideband matching constraints. Using a multiport circuit theory approach with frequency-selective scattering parameters, we propose a general framework for optimizing the MISO achievable rate that incorporates Bode-Fano wideband matching theory. We express the solution to the achievable rate optimization problem in terms of the optimized transmission coefficient and the Lagrangian parameters corresponding to the Bode-Fano inequality constraints. We apply this framework to a single electric Chu's antenna and an array of two electric Chu's antennas. We compare the optimized achievable rate obtained numerically with other benchmarks like the ideal achievable rate computed by disregarding matching constraints and the achievable rate obtained by using sub-optimal matching strategies like conjugate matching and frequency-flat transmission. We also propose a practical methodology to approximate the achievable rate bound by using the optimal transmission coefficient to derive a physically realizable matching network through the ADS software.
    摘要 “干扰网络影响电力传输自 ради频率(RF)扩展到天线。它们的设计对信号与噪音比(SNR)和可行率有影响。在这篇论文中,我们将最大化多Input单Output(MISO)系统的信号理论可行率。使用多口筒电路理论方法,我们提出一个应用各种频率选择性散射特性的通用框架,以便优化MISO可行率。我们将解决可行率最佳化问题的解释为优化传输系数和Bode-Fano干扰对称理论中的Lagrangian参数。我们将这个框架应用到单电池Chu天线和两个电池Chu天线阵列。我们比较优化的可行率与其他参考标准(例如忽略干扰限制的理论可行率和适应干扰策略如 conjugate matching和频率平坦传输)进行比较。我们还提出了一个实用的方法来近似可行率上限,通过使用最佳传输系数来 derive physically realizable干扰网络,使用ADS软件。”

Two Enhanced-rate Power Allocation Strategies for Active IRS-assisted Wireless Network

  • paper_url: http://arxiv.org/abs/2310.09721
  • repo_url: None
  • paper_authors: Qiankun Cheng, Rongen Dong, Wenlong Cai, Ruiqi Liu, Feng Shu, Jiangzhou Wang
    for:active IRS-aided network under a total power constraintmethods:adjusting power between base station (BS) and IRS, transmit beamforming at BS, reflecting beamforming at IRSresults:maximizing the SNR with two high-performance PA strategies, enhanced multiple random initialization Newton’s (EMRIN) and Taylor polynomial approximation (TPA), which perform much better than fixed PA in accordance with rate, and approach exhaustive search as the number of IRS reflecting elements increases.Here is the Chinese translation of the three key information points:for:活动反射表面协助网络下的总功率限制方法:调整基站和反射表面之间的功率,传输扫描和反射扫描结果:通过两种高性能的PA策略,即增强多random初始化Newton方法(EMRIN)和Taylor多项式approximation(TPA),实现了对级别的最大化SNR,并且比固定PA更好,随着反射表面元素的数量增加,逼近极值搜索。
    Abstract Due to its ability of overcoming the impact of double-fading effect, active intelligent reflecting surface (IRS) has attracted a lot of attention. Unlike passive IRS, active IRS should be supplied by power, thus adjusting power between base station (BS) and IRS having a direct impact on the system rate performance. In this paper, the active IRS-aided network under a total power constraint is modeled with an ability of adjusting power between BS and IRS. Given the transmit beamforming at BS and reflecting beamforming at IRS, the SNR expression is derived to be a function of power allocation (PA) factor, and the optimization of maximizing the SNR is given. Subsequently, two high-performance PA strategies, enhanced multiple random initialization Newton's (EMRIN) and Taylor polynomial approximation (TPA), are proposed. The former is to improve the rate performance of classic Netwon's method to avoid involving a local optimal point by using multiple random initializations. To reduce its high computational complexity, the latter provides a closed-form solution by making use of the first-order Taylor polynomial approximation to the original SNR function. Actually, using TPA, the original optimization problem is transformed into a problem of finding a root for a third-order polynomial.Simulation results are as follows: the first-order TPA of SNR fit its exact expression well, the proposed two PA methods performs much better than fixed PA in accordance with rate, and appoaches exhaustive search as the number of IRS reflecting elements goes to large-scale.
    摘要 因为它可以超越双折射效应的影响,活动智能反射 superficie (IRS) 已经吸引了很多关注。 unlike 被动 IRS,活动 IRS 需要接受电力供应,因此在基站 (BS) 和 IRS 之间的电力调整直接影响系统速率性能。在这篇文章中,我们模型了具有电力限制的活动 IRS-助け的网络。给定基站发射扫描和 IRS 反射扫描,我们 derivate 了 SNR 表达式,并提出了最大化 SNR 的优化问题。然后,我们提出了两种高性能 PA 策略:增强多个随机初始化 Newton 方法(EMRIN)和 Taylor polynomials 近似法(TPA)。前者是为了提高 классических Newton 方法的率性能,避免Local 优点点的涉及。而后者通过使用首颗 Taylor polynomials 近似来原 SNR 函数,提供了一个关闭式解决方案,从而减少了高计算复杂性。实际上,使用 TPA,原来的优化问题被转化为了一个找到第三阶 polynomials 的根的问题。实验结果如下:TPA 的第一阶近似与 exact 表达式很相似,而我们提出的两种 PA 方法在 accordance WITH 率性能上明显超过 fix PA,并且随着 IRS 反射元件的数量增加,两种方法的性能接近 exhaustive search。