results: 这篇论文透过实验示出了新的估计器的优越性，对于粗量化系统而言，它具有较低的平均方差误差 (MSE) 和可能的范围 (achievable rate) 等指标。Abstract
This work introduces a novel class of channel estimators tailored for coarse quantization systems. The proposed estimators are founded on conditionally Gaussian latent generative models, specifically Gaussian mixture models (GMMs), mixture of factor analyzers (MFAs), and variational autoencoders (VAEs). These models effectively learn the unknown channel distribution inherent in radio propagation scenarios, providing valuable prior information. Conditioning on the latent variable of these generative models yields a locally Gaussian channel distribution, thus enabling the application of the well-known Bussgang decomposition. By exploiting the resulting conditional Bussgang decomposition, we derive parameterized linear minimum mean square error (MMSE) estimators for the considered generative latent variable models. In this context, we explore leveraging model-based structural features to reduce memory and complexity overhead associated with the proposed estimators. Furthermore, we devise necessary training adaptations, enabling direct learning of the generative models from quantized pilot observations without requiring ground-truth channel samples during the training phase. Through extensive simulations, we demonstrate the superiority of our introduced estimators over existing state-of-the-art methods for coarsely quantized systems, as evidenced by significant improvements in mean square error (MSE) and achievable rate metrics.
摘要
results: 数值结果表明，在HDR图像恢复方面，模ulo sampling在非射频信号中具有极高的效果。Abstract
Modulo sampling and dithered one-bit quantization frameworks have emerged as promising solutions to overcome the limitations of traditional analog-to-digital converters (ADCs) and sensors. Modulo sampling, with its high-resolution approach utilizing modulo ADCs, offers an unlimited dynamic range, while dithered one-bit quantization offers cost-efficiency and reduced power consumption while operating at elevated sampling rates. Our goal is to explore the synergies between these two techniques, leveraging their unique advantages, and to apply them to non-bandlimited signals within spline spaces. One noteworthy application of these signals lies in High Dynamic Range (HDR) imaging. In this paper, we expand upon the Unlimited One-Bit (UNO) sampling framework, initially conceived for bandlimited signals, to encompass non-bandlimited signals found in the context of HDR imaging. We present a novel algorithm rigorously examined for its ability to recover images from one-bit modulo samples. Additionally, we introduce a sufficient condition specifically designed for UNO sampling to perfectly recover non-bandlimited signals within spline spaces. Our numerical results vividly demonstrate the effectiveness of UNO sampling in the realm of HDR imaging.
摘要
幂等采样和杂音一比Quantization框架已经出现为超过传统分析数字转换器（ADC）和感测器的限制的有力解决方案。幂等采样使用高分辨率的模ulo ADC，可以实现无限的动态范围，而杂音一比Quantization可以提供Cost-efficient和降低能耗的优点，同时在提高采样率时运行。我们的目标是探索这两种技术之间的相互作用，利用它们独特的优点，并应用于非射频信号内spline空间。一个值得注意的应用之一是高动态范围（HDR）图像处理。在这篇论文中，我们扩展了由带宽限制的一比 sampling框架（UNO sampling），以包括非射频信号。我们提出了一个新的算法，并且对其进行了严格的分析，以确保该算法可以从一比模ulo 样本中恢复图像。此外，我们还提出了特定于 UNO sampling的 suficient condition，以确保在spline空间中完全回收非射频信号。我们的数值结果表现了 UNO sampling在HDR图像处理中的效果。
Multivariate, Multi-step, and Spatiotemporal Traffic Prediction for NextG Network Slicing under SLA Constraints
paper_authors: Evren Tuna, Alkan Soysal for:这种研究旨在提出一种基于NextG移动网络的空间时间流量预测方法，以保证每个网络slice的服务级别协议(SLA)。methods:该方法是多变量、多步、空间时间的，利用20个无线接入网络(RAN)特征、峰值交通时间数据和移动性基于凝集来提出一个parametric SLA-based loss函数，以保证SLA违约率。results:我们的方法可以在单个维度、多个维度和slice级别进行流量预测，并对它们进行详细的比较分析。单个维度和多个维度训练架构的应用，单个维度训练可以提供单个维度级别的预测，而多个维度训练可以使用多个维度的交通数据进行预测。我们发现单个维度训练的方法可以在测试损失方面与基eline SLA-based和MAE-based模型相比，提供11.4%和38.1%的改进。此外，我们还探讨了slice级别的流量预测方法，并提出了单个slice和多个slice的方法。我们发现单个slice方法可以提供较高的测试损失改进，即28.2%, 36.4%和55.6%。Abstract
This study presents a spatiotemporal traffic prediction approach for NextG mobile networks, ensuring the service-level agreements (SLAs) of each network slice. Our approach is multivariate, multi-step, and spatiotemporal. Leveraging 20 radio access network (RAN) features, peak traffic hour data, and mobility-based clustering, we propose a parametric SLA-based loss function to guarantee an SLA violation rate. We focus on single-cell, multi-cell, and slice-based prediction approaches and present a detailed comparative analysis of their performances, strengths, and limitations. First, we address the application of single-cell and multi-cell training architectures. While single-cell training offers individual cell-level prediction, multi-cell training involves training a model using traffic from multiple cells from the same or different base stations. We show that the single-cell approach outperforms the multi-cell approach and results in test loss improvements of 11.4% and 38.1% compared to baseline SLA-based and MAE-based models, respectively. Next, we explore slice-based traffic prediction. We present single-slice and multi-slice methods for slice-based downlink traffic volume prediction, arguing that multi-slice prediction offers a more accurate forecast. The slice-based model we introduce offers substantial test loss improvements of 28.2%, 36.4%, and 55.6% compared to our cell-based model, the baseline SLA-based model, and the baseline MAE-based model, respectively.
摘要
本研究提出了下一代移动网络（NextG）的空间时间流量预测方法，以保证每个网络卷（slice）的服务水平协议（SLA）。我们的方法是多变量、多步、空间时间的。利用20个无线接入网络（RAN）特征、峰值流量时间数据和移动性基于的分群，我们提出了一个参数化的SLA基于的损失函数，以确保SLA违反率。我们关注单细胞、多细胞和卷基本预测方法，并进行了详细的比较分析其性能、优势和局限性。首先，我们讨论了单细胞和多细胞训练架构。单细胞训练提供了单细胞级别的预测，而多细胞训练则是使用多个细胞的流量来训练模型。我们发现单细胞方法比多细胞方法更高效，并在测试损失上提供了11.4%和38.1%的改进，相比基eline SLA基本模型和MAE基本模型。然后，我们探索了卷基本的流量预测。我们介绍了单卷和多卷方法 для卷基本下行流量量预测，并论证了多卷预测提供了更准确的预测。我们的卷基本模型在测试损失上提供了28.2%, 36.4%和55.6%的改进，相比我们的细胞基本模型、基eline SLA基本模型和基eline MAE基本模型。
paper_authors: Mohamed Nomeir, Sajani Vithana, Sennur Ulukus for:The paper addresses the problem of private membership aggregation (PMA), where a user wants to count the number of times an element is stored in a system of independent parties without learning which element is being counted or which party has the element.methods:The paper proposes achievable schemes for four variants of the PMA problem based on the concept of cross-subspace alignment (CSA), which achieves linear communication complexity.results:The proposed schemes achieve better privacy and security constraints than previous $K$-PSI schemes, which require exponential complexity.Abstract
We consider the problem of private membership aggregation (PMA), in which a user counts the number of times a certain element is stored in a system of independent parties that store arbitrary sets of elements from a universal alphabet. The parties are not allowed to learn which element is being counted by the user. Further, neither the user nor the other parties are allowed to learn the stored elements of each party involved in the process. PMA is a generalization of the recently introduced problem of $K$ private set intersection ($K$-PSI). The $K$-PSI problem considers a set of $M$ parties storing arbitrary sets of elements, and a user who wants to determine if a certain element is repeated at least at $K$ parties out of the $M$ parties without learning which party has the required element and which party does not. To solve the general problem of PMA, we dissect it into four categories based on the privacy requirement and the collusions among databases/parties. We map these problems into equivalent private information retrieval (PIR) problems. We propose achievable schemes for each of the four variants of the problem based on the concept of cross-subspace alignment (CSA). The proposed schemes achieve \emph{linear} communication complexity as opposed to the state-of-the-art $K$-PSI scheme that requires \emph{exponential} complexity even though our PMA problems contain more security and privacy constraints.
摘要
我们考虑private membership aggregation（PMA）问题，用户计算系统中的一个元素被多个独立点 storing 的次数。这些点不能学习用户计算的元素，也不能学习彼此的储存元素。PMA是$K$ private set intersection（$K$-PSI）问题的一般化。$K$-PSI问题中有$M$个点储存不同的元素集，并有一个用户想要找出特定元素在$M$个点中重复的至少$K$个点，而不需要学习哪个点有需要的元素和哪个点没有。为了解决PMA问题，我们将其分为四种类型根据隐私要求和数据库之间的协议。我们将这些问题转换为相应的private information retrieval（PIR）问题。我们提出了解决这四种问题的可行方案，基于横向对准（CSA）概念。我们的方案实现了线性通信复杂度，而不是现有的$K$-PSI方案，即当问题中包含更多的安全和隐私要求时，需要 exponential 复杂度。
Experimental Study of Adversarial Attacks on ML-based xApps in O-RAN
paper_authors: Naveen Naik Sapavath, Brian Kim, Kaushik Chowdhury, Vijay K Shah
For: This paper focuses on the vulnerability of ML models used in O-RAN to adversarial attacks, and the impact of such attacks on the performance of the entire O-RAN deployment.* Methods: The paper uses an example ML model for interference classification in near-real time (near-RT) RAN intelligent controllers (RIC), and demonstrates the vulnerability of this model to adversarial attacks through manipulation of data stored in a shared database inside the near-RT RIC.* Results: The paper shows that even small adversarial attacks can significantly decrease the accuracy of the interference classifier xApp using both clean and perturbed data, which can directly impact the performance of the entire O-RAN deployment.Here is the information in Simplified Chinese text:* For: 这篇论文关注了O-RAN中ML模型对抗 adversarial攻击的漏洞，以及这些攻击对整个O-RAN部署的影响。* Methods: 论文使用一个示例的ML模型来预测干扰类型，并在near-real time（near-RT）RAN智能控制器（RIC）中实际部署这个模型。* Results: 论文显示，же小的抗击攻击可以很快地降低ML应用程序的准确率，这直接影响整个O-RAN部署的性能。Abstract
Open Radio Access Network (O-RAN) is considered as a major step in the evolution of next-generation cellular networks given its support for open interfaces and utilization of artificial intelligence (AI) into the deployment, operation, and maintenance of RAN. However, due to the openness of the O-RAN architecture, such AI models are inherently vulnerable to various adversarial machine learning (ML) attacks, i.e., adversarial attacks which correspond to slight manipulation of the input to the ML model. In this work, we showcase the vulnerability of an example ML model used in O-RAN, and experimentally deploy it in the near-real time (near-RT) RAN intelligent controller (RIC). Our ML-based interference classifier xApp (extensible application in near-RT RIC) tries to classify the type of interference to mitigate the interference effect on the O-RAN system. We demonstrate the first-ever scenario of how such an xApp can be impacted through an adversarial attack by manipulating the data stored in a shared database inside the near-RT RIC. Through a rigorous performance analysis deployed on a laboratory O-RAN testbed, we evaluate the performance in terms of capacity and the prediction accuracy of the interference classifier xApp using both clean and perturbed data. We show that even small adversarial attacks can significantly decrease the accuracy of ML application in near-RT RIC, which can directly impact the performance of the entire O-RAN deployment.
摘要
Novel Power-Imbalanced Dense Codebooks for Reliable Multiplexing in Nakagami Channels
methods: 这个论文首先研究了DCMA对称错误概率（PEP）在Nakagami-$m$通道上，然后提出了一种新的设计指标called minimum logarithmic sum distance（MLSD）。
results: 对于提出的MLSD，我们引入了一种新的功率不均衡率密集代码库，通过删除特定的行来实现。 simulation results显示，我们的提出的率密集代码库可以提高 Nakagami-$m$折叠渠道下的错误性能，并且在不同的扩展因子下表现出优于现有的稀疏代码多访问和传统的unimodular DCMA方案。Abstract
This paper studies enhanced dense code multiple access (DCMA) system design for downlink transmission over the Nakagami-$m$ fading channels. By studying the DCMA pairwise error probability (PEP) in a Nakagami-$m$ channel, a novel design metric called minimum logarithmic sum distance (MLSD) is first derived. With respect to the proposed MLSD, we introduce a new family of power-imbalanced dense codebooks by deleting certain rows of a special non-unimodular circulant matrix. Simulation results demonstrate that our proposed dense codebooks lead to both larger minimum Euclidean distance and MLSD, thus yielding significant improvements of error performance over the existing sparse code multiple access and conventional unimodular DCMA schemes in Nakagami-$m$ fading channels under different overloading factors.
摘要
Space-Time Shift Keying Aided OTFS Modulation for Orthogonal Multiple Access
For: 提高高Doppler场景下的可靠上行传输* Methods: 使用Space-time shift keying-aided orthogonal time frequency space modulation-based multiple access (STSK-OTFS-MA)系统* Results: 提高多用户干扰耐受性和编码增益，并且可以实现更好的误差检测复杂度与性能质量之间的trade-off。Abstract
Space-time shift keying-aided orthogonal time frequency space modulation-based multiple access (STSK-OTFS-MA) is proposed for reliable uplink transmission in high-Doppler scenarios. As a beneficial feature of our STSK-OTFS-MA system, extra information bits are mapped onto the indices of the active dispersion matrices, which allows the system to enjoy the joint benefits of both STSK and OTFS signalling. Due to the fact that both the time-, space- and DD-domain degrees of freedom are jointly exploited, our STSK-OTFS-MA achieves increased diversity and coding gains. To mitigate the potentially excessive detection complexity, the sparse structure of the equivalent transmitted symbol vector is exploited, resulting in a pair of low-complexity near-maximum likelihood (ML) multiuser detection algorithms. Explicitly, we conceive a progressive residual check-based greedy detector (PRCGD) and an iterative reduced-space check-based detector (IRCD). Then, we derive both the unconditional single-user pairwise error probability (SU-UPEP) and a tight bit error ratio (BER) union-bound for our single-user STSK-OTFS-MA system employing the ML detector. Furthermore, the discrete-input continuous-output memoryless channel (DCMC) capacity of the proposed system is derived. The optimal dispersion matrices (DMs) are designed based on the maximum attainable diversity and coding gain metrics. Finally, it is demonstrated that our STSK-OTFS-MA system achieves both a lower BER and a higher DCMC capacity than its conventional spatial modulation (SM) {and its orthogonal frequency-division multiplexing (OFDM) counterparts. As a benefit, the proposed system strikes a compelling BER vs. system complexity as well as BER vs. detection complexity trade-offs.
摘要
Space-time shift keying-aided orthogonal time frequency space modulation-based multiple access (STSK-OTFS-MA) 是一种用于可靠的上行传输的高Doppler场景中的新系统。我们的STSK-OTFS-MA系统具有一个有利的特点，即在活动扩散矩阵上对额外信息位元进行映射，从而使系统能够同时享受STSK和OTFS信号的优点。由于系统同时利用了时间、空间和DD频域的自由度，因此我们的STSK-OTFS-MA系统可以获得更高的多样性和编码增益。为了避免可能的过分复杂的检测，我们利用了稀疏结构的等效传输符号向量，并提出了一对低复杂度的Near-Maximum Likelihood（ML）多用户检测算法：进步循环剩余检查基于的滥触检测器（PRCGD）和迭代减少空间检查基于的检测器（IRCD）。然后，我们 deriv了单用户STSK-OTFS-MA系统的无条件单用户对比误差率（SU-UPEP）和紧密的 bits错误率（BER）联合上限。此外，我们还 deriv了DCMC容量。最佳的扩散矩阵（DM）是根据最大可能的多样性和编码增益度量进行设计。最终，我们证明了我们的STSK-OTFS-MA系统在BER和DCMC容量方面都高于传统的空间模ulation（SM）和orthogonal frequency-division multiplexing（OFDM）对应系统。此外，我们的系统在BER vs. 系统复杂度和检测复杂度之间实现了惊喜的质量-精度负担。
Resource Management for IRS-assisted WP-MEC Networks with Practical Phase Shift Model
为：提高无线电力动力扩展计算能力和可持续能源供应 для低功率无线设备（WD）。* 方法：使用多个智能反射表面（IRS）来增强WP-MEC网络。jointly optimize downlink/uplink IRSs passive beamforming, downlink energy beamforming, and uplink multi-user detection (MUD) vector at HAPs, task offloading power and local computing frequency of WDs, and time slot allocation.* 结果：对于WP-MEC网络，使用实际IRS相位偏移模型可以实现更高的总计算率，比基eline方案高。Abstract
Wireless powered mobile edge computing (WP-MEC) has been recognized as a promising solution to enhance the computational capability and sustainable energy supply for low-power wireless devices (WDs). However, when the communication links between the hybrid access point (HAP) and WDs are hostile, the energy transfer efficiency and task offloading rate are compromised. To tackle this problem, we propose to employ multiple intelligent reflecting surfaces (IRSs) to WP-MEC networks. Based on the practical IRS phase shift model, we formulate a total computation rate maximization problem by jointly optimizing downlink/uplink IRSs passive beamforming, downlink energy beamforming and uplink multi-user detection (MUD) vector at HAPs, task offloading power and local computing frequency of WDs, and the time slot allocation. Specifically, we first derive the optimal time allocation for downlink wireless energy transmission (WET) to IRSs and the corresponding energy beamforming. Next, with fixed time allocation for the downlink WET to WDs, the original optimization problem can be divided into two independent subproblems. For the WD charging subproblem, the optimal IRSs passive beamforming is derived by utilizing the successive convex approximation (SCA) method and the penalty-based optimization technique, and for the offloading computing subproblem, we propose a joint optimization framework based on the fractional programming (FP) method. Finally, simulation results validate that our proposed optimization method based on the practical phase shift model can achieve a higher total computation rate compared to the baseline schemes.
摘要
无线电力驱动边缘计算（WP-MEC）已被认为是提高无线设备（WD）的计算能力和可持续能源供应的有前途的解决方案。然而，当通信链路 между混合访问点（HAP）和WDs是敌对的时，能量传输效率和任务卸载率受到影响。为解决这个问题，我们提议使用多个智能反射表面（IRS）来加入WP-MEC网络。基于实际的IRS相位偏移模型，我们将最大化总计算率问题进行联合优化，包括下降链接IRSs的过分形成、下降能量形成和上降多用户检测（MUD）向量在HAPs、任务卸载电力和本地计算频率的WDs，以及时间槽分配。Specifically, we first derive the optimal time allocation for downlink wireless energy transmission（WET）to IRSs and the corresponding energy beamforming. Next, with fixed time allocation for the downlink WET to WDs, the original optimization problem can be divided into two independent subproblems. For the WD charging subproblem, the optimal IRSs passive beamforming is derived by utilizing the successive convex approximation（SCA）method and the penalty-based optimization technique, and for the offloading computing subproblem, we propose a joint optimization framework based on the fractional programming（FP）method. Finally, simulation results validate that our proposed optimization method based on the practical phase shift model can achieve a higher total computation rate compared to the baseline schemes.
RIS-Assisted Wireless Communications: Long-Term versus Short-Term Phase Shift Designs
paper_authors: Trinh Van Chien, Lam Thanh Tu, Waqas Khalid, Heejung Yu, Symeon Chatzinotas, Marco Di Renzo
for: 提高未来无线网络的覆盖可能性和性能
methods: 使用 RIS 技术和数学优化方法
results: 提高覆盖可能性和性能，比较好于几种优化方案和 benchmarkHere’s the full translation in Simplified Chinese:
for: 这篇论文是为了提高未来无线网络的覆盖可能性和性能而写的。
methods: 这篇论文使用了 RIS 技术和数学优化方法来解决这个问题。
results: 这篇论文的结果表明，使用 RIS 技术和数学优化方法可以提高覆盖可能性和性能，并且比较好于几种优化方案和 benchmark。Abstract
Reconfigurable intelligent surface (RIS) has recently gained significant interest as an emerging technology for future wireless networks thanks to its potential for improving the coverage probability in challenging propagation environments. This paper studies an RIS-assisted propagation environment, where a source transmits data to a destination in the presence of a weak direct link. We analyze and compare RIS designs based on long-term and short-term channel statistics in terms of coverage probability and ergodic rate. For the considered optimization designs, we derive closed-form expressions for the coverage probability and ergodic rate, which explicitly unveil the impact of both the propagation environment and the RIS on the system performance. Besides the optimization of the RIS phase profile, we formulate an RIS placement optimization problem with the aim of maximizing the coverage probability by relying only on partial channel state information. An efficient algorithm is proposed based on the gradient ascent method. Simulation results are illustrated in order to corroborate the analytical framework and findings. The proposed RIS phase profile is shown to outperform several heuristic benchmarks in terms of outage probability and ergodic rate. In addition, the proposed RIS placement strategy provides an extra degree of freedom that remarkably improves system performance.
摘要
快速智能表面（RIS）在未来无线网络中已经吸引了广泛关注，因为它可以改善在困难媒体环境中的覆盖率。这篇论文研究了受助RIS的传输环境，source向目标传输数据，在弱直接链路的存在下。我们分析和比较了基于长期和短期频率统计的RIS设计，并计算了覆盖率和均衡速率。对考虑的优化设计，我们 derivated了closed-form表达式，这些表达式直接揭示了媒体环境和RIS对系统性能的影响。此外，我们提出了基于Gradient Ascent方法的RIS布局优化问题，以最大化覆盖率，只使用部分频率状态信息。实验结果表明，我们提出的RIS相位profile不仅在出入�pto�比较高，还可以在各种媒体环境下提供更好的系统性能。此外，我们的RIS布局策略提供了一个额外的自由度，可以很好地提高系统性能。