Skip to main content
CenXiv.org
此网站处于试运行阶段,支持我们!
我们衷心感谢所有贡献者的支持。
贡献
赞助
cenxiv logo > cs.IT

帮助 | 高级搜索

信息论

  • 新提交
  • 交叉列表
  • 替换

查看 最近的 文章

显示 2025年07月04日, 星期五 新的列表

总共 19 条目
显示最多 2000 每页条目: 较少 | 更多 | 所有

新提交 (展示 5 之 5 条目 )

[1] arXiv:2507.02132 [中文pdf, pdf, html, 其他]
标题: 基于矩阵束的混合接收机在快照有限场景中的到达方向估计
标题: Matrix Pencil-Based DoA Estimation for Hybrid Receivers in Snapshot-Limited Scenarios
Mona Mostafa, Ramy H. Gohary, Amr El-Keyi, Yahia A. Eldemerdash Ahmed
评论: 该手稿目前正在接受审查,以考虑在IEEE期刊上发表
主题: 信息论 (cs.IT) ; 信号处理 (eess.SP)

本文的目标是在快拍数太少以至于统计平均不可靠的情况下,估计混合模拟/数字(HAD)接收器的到达方向(DoAs)。 在全数字接收器中,这一目标是通过采用矩阵铅笔方法(MPM)来实现的。 不幸的是,由于底层模拟组合器对输出信号的纠缠,MPM无法直接应用于HAD接收器。 此外,这些模拟组合器将接收到的信号投影到一个低维空间,危及来自特定DoA范围的信号的接收。 为克服这些困难,我们提出了两种方法,使MPM能够在HAD接收器中提取DoAs。 这两种方法通过循环遍历一个全面的模拟组合器集,共同覆盖整个空间,避免了由低维投影引起的严重衰减。 第一种方法可以应用于全连接(FC)和部分连接(PC)HAD,并依赖于周期性、可能未知的信号的可用性,以解耦HAD接收器的输出。 第二种方法仅适用于PC-HAD,通过利用底层的块对角结构,消除了对周期性信号的依赖。 所提出方法的优越性通过数值仿真和与Cramér-Rao下限的比较得到验证。

The goal of this paper is to estimate the directions of arrival (DoAs) for hybrid analog/digital (HAD) receivers when the number of snapshots is too small for statistical averaging to be reliable. This goal is achieved in fully-digital receivers by employing the matrix pencil method (MPM). Unfortunately, the MPM cannot be directly applied in HAD receivers because of the entanglement induced by the underlying analog combiners on the output signals. Furthermore, these analog combiners project the received signal onto a low-dimensional space, jeopardizing the reception of signals arriving from particular DoA ranges. To circumvent these difficulties, we propose two approaches to enable the MPM to extract the DoAs in HAD receivers. The two approaches avoid severe attenuation induced by low-dimensional projection by cycling over an exhaustive set of analog combiners, collectively spanning the entire space. The first approach can be applied to both fully-connected (FC) and partially-connected (PC) HADs and relies on the availability of periodic, potentially unknown, signals to disentangle the output of the HAD receiver. The second approach applies to PC-HADs only, and eliminates contingency on periodic signals by exploiting the underlying block diagonal structure. The superiority of the proposed approaches is demonstrated via numerical simulations and comparisons with the Cram\'er-Rao lower bound.

[2] arXiv:2507.02274 [中文pdf, pdf, html, 其他]
标题: 非自适应20个问题估计在跟踪多个移动目标中的分辨率限制
标题: Resolution Limits of Non-Adaptive 20 Questions Estimation for Tracking Multiple Moving Targets
Chunsong Sun, Lin Zhou, Jingjing Wang, Weijie Yuan, Chunxiao Jiang, Alfred Hero
主题: 信息论 (cs.IT)

鉴于在多输入多输出(MIMO)通信中多个设备波束跟踪的实际应用,我们研究了在查询相关噪声信道下定位和跟踪多个移动目标的非自适应二十问题估计问题。 具体来说,我们推导了最优查询过程的分辨力的非渐近界和二阶渐近界,并提供了数值示例来说明我们的结果。 特别地,我们证明该界限可以通过在可能的目标位置上对互信息密度进行阈值处理的状态估计器实现。 与用于定位多个静止目标的多阈值方案相比,这种单一阈值解码规则降低了计算复杂度(Zhou,Bai 和 Hero,TIT 2022)。 我们讨论了我们设置中的两个特殊情况:初始位置未知且速度已知的情况,以及初始位置已知且速度未知的情况。 这两种情况都共享 Zhou,Bai 和 Hero(TIT 2022)中静态多个目标搜索的相同理论基准{适用于},而已知初始位置的情况在最大速度与查询次数成反比时接近静态目标搜索的理论基准。 我们还将结果推广以考虑 Zhou 和 Hero(TIT 2023)中引入的分段常速模型,其中目标以周期性方式改变速度。 最后,我们展示了我们提出的算法在5G无线网络中多个移动发射器波束跟踪应用中的实例。

Motivated by the practical application of beam tracking of multiple devices in Multiple Input Multiple Output (MIMO) communication, we study the problem of non-adaptive twenty questions estimation for locating and tracking multiple moving targets under a query-dependent noisy channel. Specifically, we derive a non-asymptotic bound and a second-order asymptotic bound on resolution for optimal query procedures and provide numerical examples to illustrate our results. In particular, we demonstrate that the bound is achieved by a state estimator that thresholds the mutual information density over possible target locations. This single threshold decoding rule has reduced the computational complexity compared to the multiple threshold scheme proposed for locating multiple stationary targets (Zhou, Bai and Hero, TIT 2022). We discuss two special cases of our setting: the case with unknown initial location and known velocity, and the case with known initial location and unknown velocity. Both cases share the same theoretical benchmark {that applies to} stationary multiple target search in Zhou, Bai and Hero (TIT 2022) while the known initial location case is close to the theoretical benchmark for stationary target search when the maximal speed is inversely proportional to the number of queries. We also generalize our results to account for a piecewise constant velocity model introduced in Zhou and Hero (TIT 2023), where targets change velocity periodically. Finally, we illustrate our proposed algorithm for the application of beam tracking of multiple mobile transmitters in a 5G wireless network.

[3] arXiv:2507.02303 [中文pdf, pdf, html, 其他]
标题: 基于OFDM信号的森林环境中空地一体化信道的测量与建模
标题: Measurements and Modeling of Air-Ground Integrated Channel in Forest Environment Based on OFDM Signals
Zhe Xiao, Shu Sun, Na Liu, Lianming Xu, Li Wang
主题: 信息论 (cs.IT)

森林经常受到气候条件、植被密度以及复杂的地形和地质的影响,这些因素导致自然灾害的发生。 在这样的环境中从事或支持救援行动的人员依赖于强大的通信系统来确保自身安全,这突显了在森林环境中进行信道测量的重要性。 然而,根据现有研究,目前文献中关于森林地区信道检测和建模的研究较少。 本文描述了内蒙古阿尔山国家森林公园的空中和地面信道测量活动。 它提供了地面到地面(G2G)和空中到地面(A2G)场景的测量结果和传播模型。 该测量活动使用中心频率为1.4 GHz的正交频分复用信号进行信道探测。 在G2G测量中,除了使用全向天线记录数据外,我们还使用定向天线记录信号到达接收器的角度信息。 在A2G测量中,我们预先规划无人机的飞行轨迹,使其能够以相对于地面的固定角度飞行。 我们基于测量结果的分析,提出了适用于森林环境中G2G和A2G的路径损耗模型。 结果表明,与其它路径损耗模型相比,所提出的模型减少了误差范围。 此外,我们推导了适用于森林环境的多径模型表达式,并对关键信道参数进行了统计分析,例如阴影衰落因子、均方根时延扩展和Rician K因子。 我们的研究发现,在A2G通信中,由于树冠造成的信号传播障碍比G2G通信中树干造成的障碍更为明显。 调整空中和地面之间的仰角可以提高通信质量。

Forests are frequently impacted by climate conditions, vegetation density, and intricate terrain and geology, which contribute to natural disasters. Personnel engaged in or supporting rescue operations in such environments rely on robust communication systems to ensure their safety, highlighting the criticality of channel measurements in forest environments. However, according to current research, there is limited research on channel detection and modeling in forest areas in the existing literature. This paper describes the channel measurements campaign of air and ground in the Arxan National Forest Park of Inner Mongolia. It presents measurement results and propagation models for ground-to-ground (G2G) and air-to-ground (A2G) scenarios. The measurement campaign uses orthogonal frequency division multiplexing signals centered at 1.4 GHz for channel sounding. In the G2G measurement, in addition to using omnidirectional antennas to record data, we also use directional antennas to record the arrival angle information of the signal at the receiver. In the A2G measurement, we pre-plan the flight trajectory of the unmanned aerial vehicle so that it can fly at a fixed angle relative to the ground. We present path loss models suitable for G2G and A2G in forest environments based on the analysis of measurement results. The results indicate that the proposed model reduces error margins compared with other path loss models. Furthermore, we derive the multipath model expression specific to forest environments and conduct statistical analysis on key channel parameters e.g., shadow fading factor, root mean square delay spread, and Rician K factor. Our findings reveal that signal propagation obstruction due to tree crowns in A2G communication is more pronounced than tree trunk obstructions in G2G communication. Adjusting the elevation angle between air and ground can enhance communication quality.

[4] arXiv:2507.02689 [中文pdf, pdf, html, 其他]
标题: 关于大型语言模型优化器在黑盒网络管理中的收敛性
标题: On the Convergence of Large Language Model Optimizer for Black-Box Network Management
Hoon Lee, Wentao Zhou, Merouane Debbah, Inkyu Lee
主题: 信息论 (cs.IT) ; 信号处理 (eess.SP)

未来无线网络预计将包含各种服务,这些服务通常缺乏通用的数学模型。 为了解决此类黑盒网络管理任务,最近提出了一种大型语言模型(LLM)优化器框架,该框架利用预训练的LLM作为优化代理,被视为一种有前途的解决方案。 该框架使用描述给定优化问题的自然语言提示,以及LLM自身生成的过去解决方案。 因此,LLM可以在不知道目标函数数学模型的情况下自主获得高效解决方案。 尽管LLMO框架在各种黑盒场景中的可行性已经得到研究,但迄今为止仅限于数值仿真。 本文首次为LLMO框架建立了理论基础。 通过对LLM推理步骤的仔细研究,我们可以将LLMO过程解释为一个有限状态马尔可夫链,并证明该框架的收敛性。 我们的结果扩展到了一个更先进的多LLM架构,在该架构中,从收敛速率的角度严格验证了多个LLM的影响。 全面的数值仿真验证了我们的理论结果,并提供了对LLMO框架底层机制的更深入理解。

Future wireless networks are expected to incorporate diverse services that often lack general mathematical models. To address such black-box network management tasks, the large language model (LLM) optimizer framework, which leverages pretrained LLMs as optimization agents, has recently been promoted as a promising solution. This framework utilizes natural language prompts describing the given optimization problems along with past solutions generated by LLMs themselves. As a result, LLMs can obtain efficient solutions autonomously without knowing the mathematical models of the objective functions. Although the viability of the LLM optimizer (LLMO) framework has been studied in various black-box scenarios, it has so far been limited to numerical simulations. For the first time, this paper establishes a theoretical foundation for the LLMO framework. With careful investigations of LLM inference steps, we can interpret the LLMO procedure as a finite-state Markov chain, and prove the convergence of the framework. Our results are extended to a more advanced multiple LLM architecture, where the impact of multiple LLMs is rigorously verified in terms of the convergence rate. Comprehensive numerical simulations validate our theoretical results and provide a deeper understanding of the underlying mechanisms of the LLMO framework.

[5] arXiv:2507.02731 [中文pdf, pdf, html, 其他]
标题: 基于RIS的协作ISAC网络用于结构健康监测
标题: RIS-Aided Cooperative ISAC Networks for Structural Health Monitoring
Jie Yang, Chao-Kai Wen, Xiao Li, Shi Jin
评论: 此作品已提交给IEEE以供可能发表
主题: 信息论 (cs.IT) ; 信号处理 (eess.SP)

集成感知与通信(ISAC)是未来蜂窝系统的关键特性,它利用相同的基础设施实现如入侵检测、监控和跟踪等应用。然而,由于多径干扰和需要超高的感知精度等挑战,其在结构健康监测(SHM)中的潜力尚未得到充分探索,SHM需要检测缓慢而细微的结构变化。本研究通过利用可重构智能表面(RIS)作为参考点,与基站和用户协作,引入了一种新的理论框架用于SHM。通过动态调整RIS相位以生成抑制背景多径干扰的独特无线电信号,这些参考点的测量精度得以提高。我们使用费舍尔信息理论对三维蜂窝网络中RIS辅助的协作感知进行理论分析,证明了增加观测时间、引入额外接收器(即使存在自定位误差)、优化RIS相位以及改进协作节点选择如何降低位置误差界限,以满足SHM对精度的严格要求。此外,我们开发了一个贝叶斯推断模型来识别结构状态并验证损伤检测概率。理论和数值分析均证实ISAC具备毫米级形变检测能力,突显了其在高精度SHM应用中的潜力。

Integrated sensing and communication (ISAC) is a key feature of future cellular systems, enabling applications such as intruder detection, monitoring, and tracking using the same infrastructure. However, its potential for structural health monitoring (SHM), which requires the detection of slow and subtle structural changes, remains largely unexplored due to challenges such as multipath interference and the need for ultra-high sensing precision. This study introduces a novel theoretical framework for SHM via ISAC by leveraging reconfigurable intelligent surfaces (RIS) as reference points in collaboration with base stations and users. By dynamically adjusting RIS phases to generate distinct radio signals that suppress background multipath interference, measurement accuracy at these reference points is enhanced. We theoretically analyze RIS-aided collaborative sensing in three-dimensional cellular networks using Fisher information theory, demonstrating how increasing observation time, incorporating additional receivers (even with self-positioning errors), optimizing RIS phases, and refining collaborative node selection can reduce the position error bound to meet SHM's stringent accuracy requirements. Furthermore, we develop a Bayesian inference model to identify structural states and validate damage detection probabilities. Both theoretical and numerical analyses confirm ISAC's capability for millimeter-level deformation detection, highlighting its potential for high-precision SHM applications.

交叉提交 (展示 5 之 5 条目 )

[6] arXiv:2507.02181 (交叉列表自 cs.CR) [中文pdf, pdf, html, 其他]
标题: 全9轮和减少轮数的库兹涅齐克密码的扩展c-差分区分器
标题: Extended c-differential distinguishers of full 9 and reduced-round Kuznyechik cipher
Pantelimon Stanica, Ranit Dutta, Bimal Mandal
主题: 密码学与安全 (cs.CR) ; 信息论 (cs.IT)

本文介绍了{\em 截断内部$c$-差分密码分析},一种首次使$c$-微分均匀性在分组密码中实际应用成为可能的新技术。虽然 Ellingsen 等人(IEEE Trans. Inf. Theory, 2020)使用$(F(x\oplus a), cF(x))$建立了$c$-微分均匀性的概念,但一个关键挑战依然存在:乘以$c$会破坏分组密码分析中关键加法所必需的结构特性。 我们通过开发一个\emph{内部的} $c$ -微分方法来解决这个挑战,其中乘以$c$影响输入:$(F(cx\oplus a), F(x))$。 我们证明了函数$F$的内部$c$-微分均匀性等于$F^{-1}$的外部$c$-微分均匀性,从而建立了基本的对偶性。 这种修改保留了密码结构,同时实现了实际的密码分析应用。 我们的主要贡献是一个全面的多方面统计计算框架,针对完整的9轮Kuznyechik密码实施截断的$c$-微分分析(内部$c$-差异对后端密钥异或具有免疫性)。 通过涉及数百万个微分对的广泛计算分析,我们在所有测试的轮数中都展示了统计上显著的非随机性。 对于完整的9轮密码,我们识别出多个触发关键安全警报的配置,偏差比达到$1.7\times$,校正后的p值低至$1.85 \times 10^{-3}$,这表明对这种新的攻击向量的安全性余量不足。 这是针对完整9轮Kuznyechik的第一个实际区分器。

This paper introduces {\em truncated inner $c$-differential cryptanalysis}, a novel technique that for the first time enables the practical application of $c$-differential uniformity to block ciphers. While Ellingsen et al. (IEEE Trans. Inf. Theory, 2020) established the notion of $c$-differential uniformity using $(F(x\oplus a), cF(x))$, a key challenge remained: multiplication by $c$ disrupts the structural properties essential for block cipher analysis, particularly key addition. We resolve this challenge by developing an \emph{inner} $c$-differential approach where multiplication by $c$ affects the input: $(F(cx\oplus a), F(x))$. We prove that the inner $c$-differential uniformity of a function $F$ equals the outer $c$-differential uniformity of $F^{-1}$, establishing a fundamental duality. This modification preserves cipher structure while enabling practical cryptanalytic applications. Our main contribution is a comprehensive multi-faceted statistical-computational framework, implementing truncated $c$-differential analysis against the full 9-round Kuznyechik cipher (the inner $c$-differentials are immune to the key whitening at the backend). Through extensive computational analysis involving millions of differential pairs, we demonstrate statistically significant non-randomness across all tested round counts. For the full 9-round cipher, we identify multiple configurations triggering critical security alerts, with bias ratios reaching $1.7\times$ and corrected p-values as low as $1.85 \times 10^{-3}$, suggesting insufficient security margin against this new attack vector. This represents the first practical distinguisher against the full 9-round Kuznyechik.

[7] arXiv:2507.02291 (交叉列表自 cs.LG) [中文pdf, pdf, html, 其他]
标题: 基于知识图谱的可解释和泛化的零样本语义通信
标题: Knowledge Graph-Based Explainable and Generalized Zero-Shot Semantic Communications
Zhaoyu Zhang, Lingyi Wang, Wei Wu, Fuhui Zhou, Qihui Wu
主题: 机器学习 (cs.LG) ; 人工智能 (cs.AI) ; 信息论 (cs.IT)

基于数据驱动的语义通信依赖于表面统计模式,因此缺乏可解释性和泛化能力,尤其是在存在未见过的数据的应用中。 为了解决这些挑战,我们提出了一种新颖的知识图谱增强的零样本语义通信(KGZS-SC)网络。 在基于知识图谱的语义知识库(KG-SKB)提供的结构化语义信息的指导下,我们的方案提供了泛化的语义表示,并实现了对未见过情况的推理。 具体来说,KG-SKB在共享类别语义嵌入空间中对齐语义特征,并通过对齐的语义特征增强发射机的泛化能力,从而通过选择性地传输紧凑的视觉语义来减少通信开销。 在接收端,利用零样本学习(ZSL)实现对未见过情况的直接分类,而无需重新训练或额外的计算开销,从而提高了动态或资源受限环境中的分类过程的适应性和效率。 在APY数据集上进行的仿真结果表明,所提出的KGZS-SC网络表现出强大的泛化能力,并在不同信噪比(SNR)水平下对未见过类别的分类方面显著优于现有的SC框架。

Data-driven semantic communication is based on superficial statistical patterns, thereby lacking interpretability and generalization, especially for applications with the presence of unseen data. To address these challenges, we propose a novel knowledge graph-enhanced zero-shot semantic communication (KGZS-SC) network. Guided by the structured semantic information from a knowledge graph-based semantic knowledge base (KG-SKB), our scheme provides generalized semantic representations and enables reasoning for unseen cases. Specifically, the KG-SKB aligns the semantic features in a shared category semantics embedding space and enhances the generalization ability of the transmitter through aligned semantic features, thus reducing communication overhead by selectively transmitting compact visual semantics. At the receiver, zero-shot learning (ZSL) is leveraged to enable direct classification for unseen cases without the demand for retraining or additional computational overhead, thereby enhancing the adaptability and efficiency of the classification process in dynamic or resource-constrained environments. The simulation results conducted on the APY datasets show that the proposed KGZS-SC network exhibits robust generalization and significantly outperforms existing SC frameworks in classifying unseen categories across a range of SNR levels.

[8] arXiv:2507.02732 (交叉列表自 cs.LG) [中文pdf, pdf, html, 其他]
标题: 通过分离超平面的分类:一种熵方法
标题: Classification by Separating Hypersurfaces: An Entropic Approach
Argimiro Arratia, Mahmoud El Daou, Henryk Gzyl
评论: 15页,10表,4图
主题: 机器学习 (cs.LG) ; 信息论 (cs.IT) ; 数据分析、统计与概率 (physics.data-an) ; 机器学习 (stat.ML)

我们考虑以下分类问题:给定由一组属性表示为向量的个体总体,位于${\mathbb R}^N$中,目标是在${\mathbb R}^N$中找到一个超平面,将对应于两个不同类别的点集分开。 这个问题自感知机模型以来已有悠久历史,仍然是机器学习的核心问题。 在本文中,我们通过在以原点为中心的有界$N$维超立方体内搜索参数向量,并在${\mathbb R}^M$中搜索一个正向量,通过在未知变量空间上定义的基于熵的函数的最小化来获得该向量,提出了一种新方法。 该方法可扩展到多项式曲面,允许通过更复杂的决策边界分离数据点。 这为传统的线性或二次优化技术(如支持向量机和梯度下降)提供了一种稳健的替代方案。 数值实验表明该方法在处理各种分类任务(包括线性和非线性可分性)方面的效率和通用性。

We consider the following classification problem: Given a population of individuals characterized by a set of attributes represented as a vector in ${\mathbb R}^N$, the goal is to find a hyperplane in ${\mathbb R}^N$ that separates two sets of points corresponding to two distinct classes. This problem, with a history dating back to the perceptron model, remains central to machine learning. In this paper we propose a novel approach by searching for a vector of parameters in a bounded $N$-dimensional hypercube centered at the origin and a positive vector in ${\mathbb R}^M$, obtained through the minimization of an entropy-based function defined over the space of unknown variables. The method extends to polynomial surfaces, allowing the separation of data points by more complex decision boundaries. This provides a robust alternative to traditional linear or quadratic optimization techniques, such as support vector machines and gradient descent. Numerical experiments demonstrate the efficiency and versatility of the method in handling diverse classification tasks, including linear and non-linear separability.

[9] arXiv:2507.02828 (交叉列表自 quant-ph) [中文pdf, pdf, html, 其他]
标题: 从魔术增强的克利福德电路中设计
标题: Designs from magic-augmented Clifford circuits
Yuzhen Zhang, Sagar Vijay, Yingfei Gu, Yimu Bao
评论: 59页
主题: 量子物理 (quant-ph) ; 统计力学 (cond-mat.stat-mech) ; 强关联电子 (cond-mat.str-el) ; 信息论 (cs.IT) ; 高能物理 - 理论 (hep-th)

我们引入了增强魔力的克利福德电路——一种在克利福德电路之前和/或之后添加常数深度的非克利福德(“魔力”)门电路的架构——作为一种高效利用资源来实现近似$k$设计的方法,减少了电路深度和魔力的使用。我们证明,当用常数深度的魔力门电路进行增强时,浅层克利福德电路可以生成具有$\epsilon$相对误差的近似酉和状态$k$设计。对于$N$个量子比特的这些构造,一维电路的总电路深度为$O(\log (N/\epsilon)) +2^{O(k\log k)}$,而在使用辅助量子比特的全连接电路中为$O(\log\log(N/\epsilon))+2^{O(k\log k)}$,这改进了小$k \geq 4$的先前结果。 此外,我们构造的相对误差状态$k$-设计仅涉及具有严格局部魔术的态。 当考虑具有有界加法误差的$k$-设计时,所需的魔术门数量在参数上减少了。 作为一个例子,我们证明了浅层 Clifford 电路后跟$O(k^2)$个单量子比特魔术门,与系统大小无关,可以生成一个加法误差状态$k$-设计。 我们开发了对随机电路架构的经典统计力学描述,这提供了对生成加法误差状态$k$-设计所需深度和魔术门数量的定量理解。 我们还证明了各种架构无法生成具有有界相对误差的设计的无解定理。

We introduce magic-augmented Clifford circuits -- architectures in which Clifford circuits are preceded and/or followed by constant-depth circuits of non-Clifford (``magic") gates -- as a resource-efficient way to realize approximate $k$-designs, with reduced circuit depth and usage of magic. We prove that shallow Clifford circuits, when augmented with constant-depth circuits of magic gates, can generate approximate unitary and state $k$-designs with $\epsilon$ relative error. The total circuit depth for these constructions on $N$ qubits is $O(\log (N/\epsilon)) +2^{O(k\log k)}$ in one dimension and $O(\log\log(N/\epsilon))+2^{O(k\log k)}$ in all-to-all circuits using ancillas, which improves upon previous results for small $k \geq 4$. Furthermore, our construction of relative-error state $k$-designs only involves states with strictly local magic. The required number of magic gates is parametrically reduced when considering $k$-designs with bounded additive error. As an example, we show that shallow Clifford circuits followed by $O(k^2)$ single-qubit magic gates, independent of system size, can generate an additive-error state $k$-design. We develop a classical statistical mechanics description of our random circuit architectures, which provides a quantitative understanding of the required depth and number of magic gates for additive-error state $k$-designs. We also prove no-go theorems for various architectures to generate designs with bounded relative error.

[10] arXiv:2507.02851 (交叉列表自 cs.CL) [中文pdf, pdf, html, 其他]
标题: MOTIF:通过强化微调的模块化思维在大语言模型中
标题: MOTIF: Modular Thinking via Reinforcement Fine-tuning in LLMs
Purbesh Mitra, Sennur Ulukus
主题: 计算与语言 (cs.CL) ; 人工智能 (cs.AI) ; 信息论 (cs.IT) ; 机器学习 (cs.LG) ; 系统与控制 (eess.SY)

最近在大型语言模型(LLMs)推理能力方面的进展表明,使用组相对策略优化(GRPO)算法进行强化学习(RL)训练,可以使模型在生成更好响应时使用更多的思考/推理标记。 然而,LLMs在保持对之前生成的标记的关注的同时,只能生成有限数量的标记。 这个限制,也被称为LLM的上下文大小,是LLM在任意大量标记下的推理瓶颈。 为了超越上下文大小的限制,LLM必须采用模块化思考策略来进行多轮推理。 在这项工作中,我们提出了$\textbf{MOTIF: Modular Thinking via Reinforcement Finetuning}$——一种在多轮中生成思考标记的RL训练方法,有效地使模型能够使用额外的上下文大小。 我们通过参数高效的微调,在GSM8K数据集上训练了开源模型Qwen2.5-3B-Instruct,并在MATH500和AIME2024基准测试中测试了其准确性。 我们的实验显示,在各自的基准测试中,相对于基于原始GRPO的训练,分别提高了3.8%和3.3%。 此外,这种改进仅用了15%的样本,从而展示了MOTIF的样本效率。 我们的代码和模型分别可在https://github.com/purbeshmitra/MOTIF和https://huggingface.co/purbeshmitra/MOTIF获取。

Recent advancements in the reasoning capabilities of large language models (LLMs) show that employing group relative policy optimization (GRPO) algorithm for reinforcement learning (RL) training allows the models to use more thinking/reasoning tokens for generating better responses. However, LLMs can generate only a finite amount of tokens while maintaining attention to the previously generated tokens. This limit, also known as the context size of an LLM, is a bottleneck in LLM reasoning with arbitrarily large number of tokens. To think beyond the limit of context size, an LLM must employ a modular thinking strategy to reason over multiple rounds. In this work, we propose $\textbf{MOTIF: Modular Thinking via Reinforcement Finetuning}$ -- an RL training method for generating thinking tokens in multiple rounds, effectively allowing the model to think with additional context size. We trained the open-source model Qwen2.5-3B-Instruct on GSM8K dataset via parameter efficient fine-tuning and tested its accuracy on MATH500 and AIME2024 benchmarks. Our experiments show 3.8\% and 3.3\% improvements over vanilla GRPO based training in the respective benchmarks. Furthermore, this improvement was achieved with only 15\% of samples, thus demonstrating sample efficiency of MOTIF. Our code and models are available at https://github.com/purbeshmitra/MOTIF and https://huggingface.co/purbeshmitra/MOTIF, respectively.

替换提交 (展示 9 之 9 条目 )

[11] arXiv:2404.10666 (替换) [中文pdf, pdf, 其他]
标题: 在和秩度量及坐标加法度量中的球大小界限
标题: Bounds on Sphere Sizes in the Sum-Rank Metric and Coordinate-Additive Metrics
Hugo Beeloo-Sauerbier Couvée, Thomas Jerkovits, Jessica Bariffi
主题: 信息论 (cs.IT) ; 组合数学 (math.CO)

本文提供了在任何坐标可加度量中球体大小的新界限,特别关注于改进和排名度量中的现有界限。 我们基于与玻尔兹曼分布相关的分布的熵,推导出改进的上界和下界,这些界限适用于任何坐标可加度量。 此外,我们还为和排名度量推导出新的闭式上界和下界,这些界限优于现有的闭式界限。

This paper provides new bounds on the size of spheres in any coordinate-additive metric with a particular focus on improving existing bounds in the sum-rank metric. We derive improved upper and lower bounds based on the entropy of a distribution related to the Boltzmann distribution, which work for any coordinate-additive metric. Additionally, we derive new closed-form upper and lower bounds specifically for the sum-rank metric that outperform existing closed-form bounds.

[12] arXiv:2412.04795 (替换) [中文pdf, pdf, html, 其他]
标题: 三元近极值自对偶码的长度 $36$, $48$ 和 $60$
标题: Ternary near-extremal self-dual codes of lengths $36$, $48$ and $60$
Masaaki Harada
评论: 13页
主题: 信息论 (cs.IT) ; 组合数学 (math.CO)

对于长度$36$、$48$和$60$,我们构造了新的三元接近极值自对偶码,其重量枚举式之前未知存在这样的三元接近极值自对偶码。

For lengths $36$, $48$ and $60$, we construct new ternary near-extremal self-dual codes with weight enumerators for which no ternary near-extremal self-dual codes were previously known to exist.

[13] arXiv:2501.15880 (替换) [中文pdf, pdf, html, 其他]
标题: 可移动天线遇见智能反射表面:朋友还是敌人?
标题: Movable Antennas Meet Intelligent Reflecting Surface: Friends or Foes?
Xin Wei, Weidong Mei, Qingqing Wu, Qiaoran Jia, Boyu Ning, Zhi Chen, Jun Fang
主题: 信息论 (cs.IT) ; 信号处理 (eess.SP)

可移动天线(MA)和智能反射表面(IRS)由于其共享的信道重新配置能力,被认为是下一代无线通信系统的有前途的技术。然而,这提出一个基本问题:在存在IRS的情况下,MA相对于传统固定位置天线(FPAs)的性能增益是否仍然存在?为了解答这个问题,本文研究了一个IRS辅助的多用户多输入单输出(MISO)MA系统,其中多MA基站(BS)向多个单FPAs用户发送信号。我们通过联合优化BS/IRS的主动/被动波束成形和一维发射区域内的MA位置,制定了一个总速率最大化问题,该问题难以被最优求解。为了获得本质见解,我们首先研究了一个简化的情况,即单用户情况。然后,在视线(LoS)BS-IRS信道下分析了MA相对于FPAs的性能增益,并推导出这种增益变得更大或更小的条件。此外,我们提出了一种交替优化(AO)算法,通过结合块坐标下降(BCD)方法和基于图的方法来解决单用户情况下的信噪比(SNR)最大化问题。对于一般的多用户情况,我们的性能分析揭示了在某些条件下,BS采用典型发射预编码策略时,MA相对于FPAs的性能增益会减弱。我们还通过应用结合加权最小均方误差(WMMSE)算法、流形优化方法和离散采样方法的AO算法,提出了一个高质量的次优解来解决总速率最大化问题。数值结果验证了我们的理论分析,并表明如果优化IRS的被动波束成形,MA相对于FPAs的性能增益可能会减少。

Movable antenna (MA) and intelligent reflecting surface (IRS) are considered promising technologies for the next-generation wireless communication systems due to their shared channel reconfiguration capabilities. This, however, raises a fundamental question: Does the performance gain of MAs over conventional fixed-position antennas (FPAs) still exist in the presence of the IRS? To answer this question, we investigate in this paper an IRS-assisted multi-user multiple-input single-output (MISO) MA system, where a multi-MA base station (BS) transmits to multiple single-FPA users. We formulate a sum-rate maximization problem by jointly optimizing the active/passive beamforming of the BS/IRS and the MA positions within a one-dimensional transmit region, which is challenging to be optimally solved. To drive essential insights, we first study a simplified case with a single user. Then, we analyze the performance gain of MAs over FPAs in the light-of-sight (LoS) BS-IRS channel and derive the conditions under which this gain becomes more or less significant. In addition, we propose an alternating optimization (AO) algorithm to solve the signal-to-noise ratio (SNR) maximization problem in the single-user case by combining the block coordinate descent (BCD) method and the graph-based method. For the general multi-user case, our performance analysis unveils that the performance gain of MAs over FPAs diminishes with typical transmit precoding strategies at the BS under certain conditions. We also propose a high-quality suboptimal solution to the sum-rate maximization problem by applying the AO algorithm that combines the weighted minimum mean square error (WMMSE) algorithm, manifold optimization method and discrete sampling method. Numerical results validate our theoretical analyses and demonstrate that the performance gain of MAs over FPAs may be reduced if the IRS passive beamforming is optimized.

[14] arXiv:2503.04564 (替换) [中文pdf, pdf, html, 其他]
标题: 分层安全聚合的循环用户关联的基本限制
标题: Fundamental Limits of Hierarchical Secure Aggregation with Cyclic User Association
Xiang Zhang, Zhou Li, Kai Wan, Hua Sun, Mingyue Ji, Giuseppe Caire
评论: 32页
主题: 信息论 (cs.IT) ; 人工智能 (cs.AI) ; 密码学与安全 (cs.CR) ; 分布式、并行与集群计算 (cs.DC)

安全聚合是由联邦学习(FL)所驱动的,其中云服务器旨在计算众多客户端本地训练模型的平均模型(即深度神经网络的权重),同时遵守数据安全要求。 分层安全聚合(HSA)将这一概念扩展到三层分层网络,其中聚类用户通过中继层与服务器通信。 在HSA中,除了传统的服务器安全外,还强制实施中继安全,以确保中继对用户的输入保持不知情(这是FL中本地模型的抽象)。 现有的HSA研究假设每个用户仅关联一个中继,这限制了跨集群用户进行编码以实现高效通信和密钥生成的机会。 在本文中,我们考虑一种循环关联模式下的HSA,其中每个用户以环绕方式连接到$B$个连续的中继。 我们提出了一种高效的聚合方案,其中包括一种受梯度编码启发的输入消息设计——这是一种在分布式计算中用于高效通信的知名技术,以及一种高度非显而易见的安全密钥设计。 我们还使用信息论论证推导了通信和密钥速率的最小可实现值的新下界。

Secure aggregation is motivated by federated learning (FL) where a cloud server aims to compute an averaged model (i.e., weights of deep neural networks) of the locally-trained models of numerous clients, while adhering to data security requirements. Hierarchical secure aggregation (HSA) extends this concept to a three-layer hierarchical network, where clustered users communicate with the server through an intermediate layer of relays. In HSA, beyond conventional server security, relay security is also enforced to ensure that the relays remain oblivious to the users' inputs (an abstraction of the local models in FL). Existing study on HSA assumes that each user is associated with only one relay, limiting opportunities for coding across inter-cluster users to achieve efficient communication and key generation. In this paper, we consider HSA with a cyclic association pattern where each user is connected to $B$ consecutive relays in a wrap-around manner. We propose an efficient aggregation scheme which includes a message design for the inputs inspired by gradient coding-a well-known technique for efficient communication in distributed computing-along with a highly non-trivial security key design. We also derive novel converse bounds on the minimum achievable communication and key rates using information-theoretic arguments.

[15] arXiv:2506.10374 (替换) [中文pdf, pdf, html, 其他]
标题: 具有单边错误保证的最优非自适应组测试
标题: Optimal Non-Adaptive Group Testing with One-Sided Error Guarantees
Daniel McMorrow, Jonathan Scarlett
主题: 信息论 (cs.IT) ; 统计理论 (math.ST)

群体测试问题包括通过一系列测试从较大的物品集合中确定一个稀疏的缺陷物品子集,其中每个测试结果指示测试中是否包含至少一个缺陷物品。 我们研究了近似恢复设置,在这种情况下,缺陷集的恢复标准被放宽,允许少量物品被错误分类。 特别是,我们考虑单边近似恢复标准,其中只允许出现假阴性或假阳性错误分类。 在仅存在假阴性的情况下(即找到缺陷物品的一个子集),我们展示了存在一种算法匹配双边近似恢复的最优阈值。 在仅存在假阳性的情况下(即找到缺陷物品的一个超集),我们提供了一个逆向界限,表明现有两种算法中较好的一种是最佳的。

The group testing problem consists of determining a sparse subset of defective items from within a larger set of items via a series of tests, where each test outcome indicates whether at least one defective item is included in the test. We study the approximate recovery setting, where the recovery criterion of the defective set is relaxed to allow a small number of items to be misclassified. In particular, we consider one-sided approximate recovery criteria, where we allow either only false negative or only false positive misclassifications. Under false negatives only (i.e., finding a subset of defectives), we show that there exists an algorithm matching the optimal threshold of two-sided approximate recovery. Under false positives only (i.e., finding a superset of the defectives), we provide a converse bound showing that the better of two existing algorithms is optimal.

[16] arXiv:2507.00609 (替换) [中文pdf, pdf, html, 其他]
标题: 关于$M$-码的秩权重层次
标题: On the rank weight hierarchy of $M$-codes
G. Berhuy, J. Molina
主题: 信息论 (cs.IT)

我们研究在基域上定义的线性自同态下稳定的线性码的秩权重层次,特别是当自同态是循环的时候。在最后一种情况下,我们给出了这样的码的第一个秩权重等于$1$的必要且充分条件,以及其最后一个秩权重的显式公式。

We study the rank weight hierarchy of linear codes which are stable under a linear endomorphism defined over the base field, in particular when the endomorphism is cyclic. In this last case, we give a necessary and sufficient condition for such a code to have first rank weight equal to $1$ in terms of its generator polynomial, as well as an explicit formula for its last rank weight.

[17] arXiv:2507.01641 (替换) [中文pdf, pdf, html, 其他]
标题: 多RIS辅助系统中的联合空间分区分复用与定制正交组信道
标题: Joint Spatial Division and Multiplexing with Customized Orthogonal Group Channels in Multi-RIS-Assisted Systems
Weicong Chen, Chao-Kai Wen, Wankai Tang, Xiao Li, Shi Jin
评论: 此作品已提交给IEEE以供可能发表
主题: 信息论 (cs.IT) ; 信号处理 (eess.SP)

可重构智能表面(RISs)提供了重塑无线环境的独特能力,从而简化了传统上依赖于信道状况的传输方案。联合空间分隔和复用(JSDM)作为一种低开销的多用户设备(UE)场景传输方案出现,通常需要复杂的矩阵分解以实现有效信道矩阵的块对角化。在本研究中,我们引入了一种创新的JSDM设计,利用RISs定制信道,从而简化整体流程。通过在基站(BS)的离散傅里叶变换(DFT)方向上战略性地放置RISs,我们在BS-RIS信道内建立了正交视距链路,使得预波束成形设计变得简单。基于UE分组,我们设计了RIS的反射波束,使其方向优化,以减轻RISs-UEs信道中的组间干扰。推导出信道交叉相关系数的近似值,并作为RISs-UEs关联的基础,进一步减少组间干扰。数值结果证明了我们的RIS定制JSDM的有效性,不仅实现了有效信道的块对角化,还显著提高了多UE传输的总频谱效率。

Reconfigurable intelligent surfaces (RISs) offer the unique capability to reshape the radio environment, thereby simplifying transmission schemes traditionally contingent on channel conditions. Joint spatial division and multiplexing (JSDM) emerges as a low-overhead transmission scheme for multi-user equipment (UE) scenarios, typically requiring complex matrix decomposition to achieve block-diagonalization of the effective channel matrix. In this study, we introduce an innovative JSDM design that leverages RISs to customize channels, thereby streamlining the overall procedures. By strategically positioning RISs at the discrete Fourier transform (DFT) directions of the base station (BS), we establish orthogonal line-of-sight links within the BS-RIS channel, enabling a straightforward pre-beamforming design. Based on UE grouping, we devise reflected beams of the RIS with optimized directions to mitigate inter-group interference in the RISs-UEs channel. An approximation of the channel cross-correlation coefficient is derived and serves as a foundation for the RISs-UEs association, further diminishing inter-group interference. Numerical results substantiate the efficacy of our RIS-customized JSDM in not only achieving effective channel block-diagonalization but also in significantly enhancing the sum spectral efficiency for multi-UE transmissions.

[18] arXiv:2507.01685 (替换) [中文pdf, pdf, html, 其他]
标题: 半空间耦合涡轮类码
标题: Half Spatially Coupled Turbo-Like Codes
Xiaowei Wu, Lei Yang, Min Qiu, Chong Han, Jinhong Yuan
评论: 这是会议论文“半空间耦合Turbo-like码”的扩展版本,已被2025年IEEE信息论研讨会接受。
主题: 信息论 (cs.IT)

本文提出了一类新的空间耦合涡轮类码(SC-TCs),即半空间耦合交织卷积码(HSC-BCCs)和半空间耦合并行级联码(HSC-PCCs)。与传统的SC-TCs不同,所提出的码具有更简单和确定的耦合结构。最显著的是,HSC-BCCs的耦合是通过在某一时间实例的分量编码器中重新编码整个耦合序列来实现的,而不是将耦合比特分散到多个时间实例的分量编码器中。这种简化不仅解决了现有BCCs中的窗口解码阈值损失问题,还使得所提出的码在耦合记忆仅为2的情况下能够达到非常接近容量的性能。提供了理论和数值结果来展示所提出码相对于现有空间耦合码的性能优势。

This paper presents a new class of spatially coupled turbo-like codes (SC-TCs), namely half spatially coupled braided convolutional codes (HSC-BCCs) and half spatially coupled parallel concatenated codes (HSC-PCCs). Different from the conventional SC-TCs, the proposed codes have simpler and deterministic coupling structures. Most notably, the coupling of HSC-BCCs is performed by re-encoding the whole coupling sequence in the component encoder of one time instant, rather than spreading the coupling bits to component encoders of multiple time instants. This simplification not only addresses the window decoding threshold loss issue in existing BCCs, but also allows the proposed codes to attain very close-to-capacity performance with a coupling memory as small as 2. Both theoretical and numerical results are provided to demonstrate the performance advantages of the proposed codes over existing spatially coupled codes.

[19] arXiv:2412.21171 (替换) [中文pdf, pdf, html, 其他]
标题: 接近编码理论界限的量子纠错
标题: Quantum Error Correction near the Coding Theoretical Bound
Daiki Komoto, Kenta Kasai
评论: 此工作已提交至期刊以供可能发表
主题: 量子物理 (quant-ph) ; 信息论 (cs.IT)

最近在量子计算方面的进展使得系统能够拥有数十个可靠的逻辑量子比特,这些逻辑量子比特由数千个噪声物理量子比特构建而成。 然而,许多有影响力的应用需要具有数百万个逻辑量子比特的量子计算,这需要高度可扩展的量子纠错。 在经典信息理论中,低密度奇偶校验(LDPC)码可以高效地接近信道容量。 尽管经过数十年的研究,但尚未显示出具有高效解码的量子纠错码可以接近哈希界限——这是量子容量的基本限制。 在这里,我们提出了量子LDPC码,它们不仅接近哈希界限,而且允许以物理量子比特数量线性的方式进行解码。 这一突破为大规模、容错的量子计算铺平了道路。 结合能够管理大量量子比特的新兴硬件,我们的方法使量子解决方案更接近现实中的重要问题。

Recent progress in quantum computing has enabled systems with tens of reliable logical qubits, built from thousands of noisy physical qubits. However, many impactful applications demand quantum computations with millions of logical qubits, necessitating highly scalable quantum error correction. In classical information theory, low-density parity-check (LDPC) codes can approach channel capacity efficiently. Yet, no quantum error-correcting codes with efficient decoding have been shown to approach the hashing bound - a fundamental limit on quantum capacity - despite decades of research. Here, we present quantum LDPC codes that not only approach the hashing bound but also allow decoding with computational cost linear in the number of physical qubits. This breakthrough paves the way for large-scale, fault-tolerant quantum computation. Combined with emerging hardware that manages many qubits, our approach brings quantum solutions to important real-world problems significantly closer to reality.

总共 19 条目
显示最多 2000 每页条目: 较少 | 更多 | 所有
  • 关于
  • 帮助
  • contact arXivClick here to contact arXiv 联系
  • 订阅 arXiv 邮件列表点击这里订阅 订阅
  • 版权
  • 隐私政策
  • 网络无障碍帮助
  • arXiv 运营状态
    通过...获取状态通知 email 或者 slack

京ICP备2025123034号