Systems and Control
A Unified Low-rank ADI Framework with Shared Linear Solves for Simultaneously Solving Multiple Lyapunov, Sylvester, and Riccati Equations
Umair Zulfiqar, Zhong-Yi Huang, Qiu-Yan Song et al. (+1 more)
The alternating direction implicit (ADI) methods are computationally efficient and numerically effective tools for computing low-rank solutions of large-scale linear
matrix equations. It is known in the literature that the low-rank ADI method for Lyapunov equations is a Petrov-Galerkin projection
algorithm that implicitly performs model order reduction. It recursively enforces interpolation at the mirror images of the ADI shifts and places the poles of the reduced-order models at the ADI shifts. In this paper, we show that the low-rank ADI methods for Sylvester and Riccati equations are also Petrov-Galerkin projection
algorithms that implicitly perform model order reduction. These methods likewise enforce interpolation at the mirror images of the ADI shifts; however, they do not place the poles at the mirror images of the interpolation points. Instead, their pole placement ensures that the projected Sylvester and Riccati equations they implicitly solve admit a unique solution. By observing that the ADI methods for Lyapunov, Sylvester, and Riccati equations differ only in pole placement and not in their interpolatory nature, we show that the shifted linear solves-which constitute the bulk of the computational cost-can be shared. The pole-placement step involves only small-scale operations and is therefore inexpensive. We propose a unified ADI framework that requires only two shifted linear solves per iteration to simultaneously solve six Lyapunov equations, one Sylvester equation, and ten Riccati equations, thus substantially increasing the return on investment for the computational cost spent on the linear solves. All operations needed to extract the individual solutions from these shared linear solves are small-scale and inexpensive. Three numerical examples are presented to demonstrate the effectiveness of the proposed ADI framework.
Read the full abstract ▾
All authors Umair Zulfiqar, Zhong-Yi Huang, Qiu-Yan Song, Zhi-Yuan Gao
Systems and Control
Auto-Optimization with Active Learning in Uncertain Environment: A Predictive Control Approach
Yuan Tan, Jun Yang, Zhongguo Li et al. (+2 more)
This paper presents an auto-optimal model predictive control (MPC) framework enhanced with active learning, designed to autonomously track optimal operational conditions in an unknown environment,where the conditions may dynamically adjust to environmental changes. First, an exploitation-oriented MPC (EO-MPC) is proposed, integrating real-time sampling data with robust set-based parameter estimation techniques to address the critical challenge of parameter identification. By introducing virtual excitation signals into the terminal constraint and establishing a validation mechanism for persistent excitation condition, the EO-MPC effectively resolves the issue of insufficient persistent excitation in parameter identification. Building upon this foundation, an active learning MPC (AL-MPC) approach is developed to integrate both available and virtual future data to resolve the fundamental conflict between tracking an unknown optimal operational condition and parameter identification. The recursive feasibility and convergence of the proposed methods are rigorously established, and numerous examples substantiate the reliability and effectiveness of the approach in practical applications.
Read the full abstract ▾
All authors Yuan Tan, Jun Yang, Zhongguo Li, Wen-Hua Chen, Shihua Li
Systems and Control
Strategies for zero boil-off liquid hydrogen transfer: an export terminal case-study
Halvor Aarnes Krog and David Berstad
To ensure economic viability, LH2 export terminals must minimize boil-off losses. We show two strategies to achieve zero boil-off losses for the transfer of 160 000 m3 LH2 (11 248 tons) using a centrifugal pump. In the first strategy, a pump with variable speed drive (VSD) and split-range control for the flow rate achieves losses from 0 wt% to 0.24 wt% in an uncertainty analysis. A pump efficiency approaching 70% is the most important factor to minimize losses. In contrast, a fixed-speed pump has unacceptably high losses ranging from 0.76 wt% to 1.06 wt% (119 tons per ship). The second strategy is to increase the maximum pressure in the seaborne tank (base case is 1.15 bara). Zero loss is achieved for the fixed speed pump if the maximum pressure is increased to 1.35 bara, while 1.22 bara is required for the pump with VSD assuming an efficiency of 60%.
Read the full abstract ▾
Signal Processing
Nonlinear EM-based Signal Processing
Mattia Fabiani, Giulia Torcolacci and Davide Dardari
The use of high-frequency bands, combined with
antenna arrays containing an extremely large number of elements (XL-
MIMO), is pushing current technology to its limits in terms of hardware complexity, latency, and power consumption. A promising approach to achieving scalable and sustainable solutions is to shift part of the signal processing directly into the electromagnetic (EM) domain. In this paper, we investigate novel architectures that harness the interaction of reconfigurable passive linear and nonlinear (NL) scattering elements positioned in the reactive near field of signal sources. The objective is to enable multifunctional linear and NL EM signal processing to occur directly "over-the-air." Numerical results highlight the potential to significantly reduce both system complexity and the number of RF chains, while still achieving key performance metrics in applications such as direction-of-arrival and position estimation, without the need for additional analog or digital processing.
Read the full abstract ▾
Image and Video Processing
Structure-Aware Adaptive Kernel MPPCA Denoising for Diffusion MRI
Ananya Singhal, Dattesh Dayanand Shanbhag and Sudhanya Chatterjee
Diffusion-weighted MRI (DWI) at high b-values often suffers from low signal-to-noise ratio (SNR), making image quality poor. Marchenko-Pastur PCA (MPPCA) is a popular method to reduce noise, but it uses a fixed patch size across the whole image, which doesn't work well in regions with different structures. To address this, we propose an adaptive kernel MPPCA (ak-MPPCA) that selects the best patch size for each voxel based on its local neighborhood. This improves denoising performance by better handling structural variations.
Read the full abstract ▾
Systems and Control
Gauss-Newton accelerated MPPI Control
Hannes Homburger, Katrin Baumgärtner, Moritz Diehl et al. (+1 more)
Model Predictive Path Integral (MPPI) control is a sampling-based optimization method that has recently attracted
attention, particularly in the robotics and reinforcement learning communities. MPPI has been widely applied as a GPU-accelerated random search method to deterministic direct single-shooting optimal control problems arising in model predictive control (MPC) formulations. MPPI offers several key advantages, including flexibility, robustness, ease of implementation, and inherent parallelizability. However, its performance can deteriorate in high-dimensional settings since the optimal control problem is solved via Monte Carlo sampling. To address this limitation, this paper proposes an enhanced MPPI method that incorporates a Jacobian reconstruction technique and the second-order Generalized Gauss-Newton method. This novel approach is called Gauss-Newton accelerated MPPI. The numerical results show that the Gauss-Newton accelerated MPPI approach substantially improves MPPI scalability and computational efficiency while preserving the key benefits of the classical MPPI framework, making it a promising approach even for high-dimensional problems.
Read the full abstract ▾
All authors Hannes Homburger, Katrin Baumgärtner, Moritz Diehl, Johannes Reuter
Systems and Control
Adapt and Stabilize, Then Learn and Optimize: A New Approach to Adaptive LQR
Peter A. Fisher and Anuradha M. Annaswamy
This paper focuses on adaptive control of the discrete-time linear quadratic regulator (adaptive LQR). Recent literature has made significant contributions in proving non-asymptotic convergence rates, but existing approaches have a few drawbacks that pose barriers for practical implementation. These drawbacks include (i) a requirement of an initial stabilizing controller, (ii) a reliance on exploration for closed-loop stability, and/or (iii) computationally intensive
algorithms. This paper proposes a new
algorithm that overcomes these drawbacks for a particular class of discrete-time systems. This
algorithm leverages direct model-reference adaptive control (direct MRAC) and combines it with an epoch-based approach in order to address the drawbacks (i)-(iii) with a provable high-probability regret bound comparable to existing literature. Simulations demonstrate that the proposed approach yields regrets that are comparable to those from existing methods when the conditions (i) and (ii) are met, and yields regrets that are significantly smaller when either of these two conditions is not met.
Read the full abstract ▾
Systems and Control · Cross-listed from cs.GT
Omniscient Attacker in Stochastic Security Games with Interdependent Nodes
Yuksel Arslantas, Ahmed Said Donmez, Ege Yuceel et al. (+1 more)
The adoption of reinforcement learning for critical infrastructure defense introduces a vulnerability where sophisticated attackers can strategically exploit the defense
algorithm's learning dynamics. While prior work addresses this vulnerability in the context of repeated normal-form games, its extension to the
stochastic games remains an open research gap. We close this gap by examining
stochastic security games between an RL defender and an omniscient attacker, utilizing a tractable linear influence network model. To overcome the structural limitations of prior methods, we propose and apply neuro-dynamic programming. Our experimental results demonstrate that the omniscient attacker can significantly outperform a naive defender, highlighting the critical vulnerability introduced by the learning dynamics and the effectiveness of the proposed strategy.
Read the full abstract ▾
All authors Yuksel Arslantas, Ahmed Said Donmez, Ege Yuceel, Muhammed O. Sayin
Systems and Control
Efficient Safety Verification of Autonomous Vehicles with Neural Network Operator
Lingxiang Fan, Linxuan He, Haoyuan Ji et al. (+1 more)
When autonomous vehicles encounter untrained scenarios, ensuring safety hinges on effective safety verification to prevent accidents stemming from unexpected model decisions. Reachability analysis, a method of safety verification, offers relatively high precision but at the cost of significant computational complexity. Our method leverages end-to-end neural network operators to compute reachable sets, replacing traditional mathematical set operators, thereby achieving higher efficiency in safety verification without substantially compromising accuracy or increasing conservativeness. We define vehicle dynamics on discrete time series and detail the safety verification process and safety standard based on reachable sets. Experimental evaluations conducted in several typical road driving scenarios demonstrate the superior efficiency performance of our proposed operator over classical methods.
Read the full abstract ▾
All authors Lingxiang Fan, Linxuan He, Haoyuan Ji, Shuo Feng
Audio and Speech Processing · Cross-listed from cs.SD
RRPO: Robust Reward Policy Optimization for LLM-based Emotional TTS
Cong Wang, Changfeng Gao, Yang Xiang et al. (+7 more)
Differentiable reinforcement learning (RL) frameworks like DiffRO offer a powerful approach for controllable text-to-
speech (TTS), but are vulnerable to reward hacking, particularly for nuanced tasks like
emotion control. The policy model can exploit a vanilla Reward Model (RM) by generating acoustic artifacts to achieve spurious rewards, but at the cost of degrading perceptual quality. To address this, we propose Robust Reward Policy Optimization (RRPO), a novel framework that employs a hybrid regularization scheme. This scheme develops a robust RM whose reward signal is more reliably aligned with human perception, compelling the policy to abandon detrimental shortcuts and instead learn the complex features of genuine
emotions. Our ablation study confirms the enhanced robustness of our RM, as evidenced by its strong cross-lingual generalization. The subjective evaluation demonstrates that this robust RM effectively mitigates reward hacking, leading to significant improvements in both emotional expressiveness and naturalness over all baselines. Demo page: https://lrwinr.github.io/RRPO-CosyVoice.
Read the full abstract ▾
All authors Cong Wang, Changfeng Gao, Yang Xiang, Zhihao Du, Keyu An, Han Zhao, Qian Chen, Xiangang Li, Yingming Gao, Ya Li
Audio and Speech Processing · Cross-listed from cs.SD
Multi-Loss Learning for Speech Emotion Recognition with Energy-Adaptive Mixup and Frame-Level Attention
Cong Wang, Yizhong Geng, Yuhua Wen et al. (+7 more)
Speech emotion recognition (SER) is an important technology in human-computer interaction. However, achieving high performance is challenging due to emotional complexity and scarce annotated data. To tackle these challenges, we propose a multi-loss learning (MLL) framework integrating an energy-adaptive mixup (EAM) method and a frame-level
attention module (FLAM). The EAM method leverages SNR-based augmentation to generate diverse
speech samples capturing subtle emotional variations. FLAM enhances frame-level feature extraction for multi-frame emotional cues. Our MLL strategy combines Kullback-Leibler divergence, focal, center, and supervised contrastive loss to optimize learning, address class imbalance, and improve feature separability. We evaluate our method on four widely used SER
datasets: IEMOCAP, MSP-IMPROV, RAVDESS, and SAVEE. The results demonstrate our method achieves state-of-the-art performance, suggesting its effectiveness and robustness.
Read the full abstract ▾
All authors Cong Wang, Yizhong Geng, Yuhua Wen, Qifei Li, Yingming Gao, Ruimin Wang, Chunfeng Wang, Hao Li, Ya Li, Wei Chen
Systems and Control · Cross-listed from math.OC
An accelerated proximal bundle method for convex optimization
Feng-Yi Liao, Thomas Madden and Yang Zheng
The proximal bundle method (PBM) is a powerful and widely used approach for minimizing nonsmooth convex functions. However, for smooth objectives, its best-known convergence rate remains suboptimal, and whether PBM can be accelerated remains open. In this work, we present the first accelerated proximal bundle method that achieves the optimal $\mathscr{O}(1/\sqrt{\epsilon})$ iteration complexity for obtaining an $\epsilon$-accurate solution in smooth convex optimization. The proposed method is conceptually simple, which differs from Nesterov's accelerated gradient descent by only a single line and retains all key structural properties of the classical PBM. In particular, it relies on the same minimal assumptions on model approximations and preserves the standard bundle testing criterion. Numerical experiments confirm the accelerated $\mathscr{O}(1/\sqrt{\epsilon})$ convergence rate predicted by our theory.
Read the full abstract ▾
Signal Processing · Cross-listed from cs.CV
WiFi-based Cross-Domain Gesture Recognition Using Attention Mechanism
Ruijing Liu, Cunhua Pan, Jiaming Zeng et al. (+4 more)
While fulfilling communication tasks, wireless signals can also be used to sense the environment. Among various types of sensing media, WiFi signals offer advantages such as widespread availability, low hardware cost, and strong robustness to environmental conditions like light, temperature, and humidity. By analyzing Wi-Fi signals in the environment, it is possible to capture dynamic changes of the human body and accomplish sensing applications such as gesture recognition. Although many existing gesture sensing solutions perform well in-domain but lack cross-domain capabilities (i.e., recognition performance in untrained environments). To address this, we extract Doppler spectra from the channel state information (CSI) received by all receivers and concatenate each Doppler spectrum along the same time axis to generate fused images with multi-angle information as input features. Furthermore, inspired by the convolutional block
attention module (CBAM), we propose a gesture recognition network that integrates a multi-semantic spatial
attention mechanism with a self-
attention-based channel mechanism. This network constructs
attention maps to quantify the spatiotemporal features of gestures in images, enabling the extraction of key domain-independent features. Additionally, ResNet18 is employed as the backbone network to further capture deep-level features. To validate the network performance, we evaluate the proposed network on the public Widar3
dataset, and the results show that it not only maintains high in-domain accuracy of 99.72%, but also achieves high performance in cross-domain recognition of 97.61%, significantly outperforming existing best solutions.
Read the full abstract ▾
All authors Ruijing Liu, Cunhua Pan, Jiaming Zeng, Hong Ren, Kezhi Wang, Lei Kong, Jiangzhou Wang
Systems and Control
Adaptive Time-Domain Harmonic Control for Noise-Vibration-Harshness Reduction of Electric Drives
Klaus Herburger, Fabian Jakob, David Gänzle et al. (+2 more)
Reducing Noise, Vibration, and Harshness (NVH) in electric drives is crucial for applications such as electric vehicle drivetrains and heat-pump compressors, where strict NVH requirements directly affect user satisfaction and component longevity. This work presents the integration of an adaptive time-domain harmonic controller into an existing electric-drive control loop to attenuate harmonic disturbances. Three control structures are proposed and analyzed, along with a modified parameter-estimation scheme that reduces computational effort while preserving estimation accuracy, making the method suitable for embedded real-time implementation. To cope with fast operating-point changes, a delta-learning approach combines adaptive control with a lookup-table-based feedforward
estimator, ensuring fast convergence and robustness. The proposed controller architectures are validated through simulation and testbench experiments on a permanent-magnet synchronous machine drive, demonstrating substantial NVH reductions across operating conditions. The results confirm that time-domain adaptive harmonic control offers a practical and theoretically grounded solution for real-time NVH mitigation in electric drives.
Read the full abstract ▾
All authors Klaus Herburger, Fabian Jakob, David Gänzle, Maximilian Manderla, Andrea Iannelli
Systems and Control · Cross-listed from cs.AI
Prescriptive Artificial Intelligence: A Formal Paradigm for Auditing Human Decisions Under Uncertainty
Pedro Passos
We formalize Prescriptive Artificial Intelligence as a distinct paradigm for human-AI decision collaboration in high-stakes,
stochastic environments involving single-
agent individual decision-making. Unlike predictive systems optimized for outcome accuracy, prescriptive systems audit human decisions under uncertainty, providing normative guidance while preserving human agency and accountability. We introduce four domain-independent axioms characterizing prescriptive systems and prove fundamental separation results. Central is the Imitation Incompleteness
theorem: supervised learning from historical decisions cannot correct systematic biases in the absence of external normative signals. Under standard regularity conditions, the induced predictor converges almost surely to the biased action rather than the normatively optimal one. Performance in decision imitation is therefore bounded by a structural bias term (epsilon_bias) rather than the statistical rate O(1/sqrt(n)), a result extended to Markovian logs and finite-sample concentration bounds. We demonstrate realizability through three independent instantiations spanning five decades: an interpretable fuzzy system for elite soccer
auditing, revealing decision latency and risk states obscured by outcome and status quo biases; MYCIN, the historically validated rule-based clinical consultation system; and NEWS2, a nationally mandated clinical protocol validated on a prospective multi-center cohort. The framework establishes Prescriptive AI as a general, realizable class of decision-support systems for safety-critical domains where interpretability, contestability, and normative
alignment are essential.
Read the full abstract ▾
Systems and Control
Optimizing DER Aggregate Flexibility via Network Reconfiguration
Feixiang Zhang, Hongyi Li, Bai Cui et al. (+1 more)
The aggregate flexibility region of distributed energy resources (DERs) quantifies the aggregate power shaping capabilities of DERs. It characterizes the distribution network's potential for wholesale
market participation and grid service provision at the transmission level. To enhance flexibility and fully exploit the potential of DERs, this paper proposes a method to optimize the aggregate flexibility region through distribution network reconfiguration. First, we formulate the ellipsoidal aggregate flexibility region characterization problem as a two-stage adaptive robust optimization problem and derive an exact convex reformulation with a large number of second-order cone constraints. By exploiting the problem structure, we propose a scalable Benders decomposition
algorithm with provable finite convergence to the optimal solution. Finally, we propose an optimal reconfiguration problem for aggregate flexibility region optimization and solve it using the custom Benders decomposition. Numerical simulations on the IEEE 123-bus test feeder demonstrate that, compared to existing approaches, substantial improvements in the aggregate flexibility region can be achieved over multiple scenarios with the optimized
topology.
Read the full abstract ▾
All authors Feixiang Zhang, Hongyi Li, Bai Cui, Zhaoyu Wang
Signal Processing · Cross-listed from cs.IT
Joint Low-Rank and Sparse Bayesian Channel Estimation for Ultra-Massive MIMO Communications
Jianghan Ji, Cheng-Xiang Wang, Shuaifei Chen et al. (+3 more)
This letter investigates channel estimation for ultra-massive multiple-input multiple-output (
MIMO) communications. We propose a joint low-rank and sparse
Bayesian estimation (LRSBE)
algorithm for spatial non-stationary ultra-massive channels by exploiting the low-rankness and sparsity in the beam domain. Specifically, the channel estimation integrates sparse
Bayesian learning and soft-threshold gradient descent within the expectation-maximization framework. Simulation results show that the proposed
algorithm significantly outperforms the state-of-the-art alternatives under different signal-to-noise ratio conditions in terms of estimation accuracy and overall complexity.
Read the full abstract ▾
All authors Jianghan Ji, Cheng-Xiang Wang, Shuaifei Chen, Chen Huang, Xiping Wu, Emil Björnson
Systems and Control · Cross-listed from cs.RO
Vision-Language-Action Models for Selective Robotic Disassembly: A Case Study on Critical Component Extraction from Desktops
Chang Liu, Sibo Tian, Sara Behdad et al. (+2 more)
Automating disassembly of critical components from end-of-life (EoL) desktops, such as high-value items like RAM modules and CPUs, as well as sensitive parts like hard disk drives, remains challenging due to the inherent variability and uncertainty of these products. Moreover, their disassembly requires sequential, precise, and dexterous operations, further increasing the complexity of automation. Current robotic disassembly processes are typically divided into several stages: perception, sequence planning, task planning, motion planning, and manipulation. Each stage requires explicit modeling, which limits generalization to unfamiliar scenarios. Recent development of
vision-
language-action (VLA) models has presented an end-to-end approach for general robotic manipulation tasks. Although VLAs have demonstrated promising performance on simple tasks, the feasibility of applying such models to complex disassembly remains largely unexplored. In this paper, we collected a customized
dataset for robotic RAM and CPU disassembly and used it to fine-tune two well-established VLA approaches, OpenVLA and OpenVLA-OFT, as a case study. We divided the whole disassembly task into several small steps, and our preliminary experimental results indicate that the fine-tuned VLA models can faithfully complete multiple early steps but struggle with certain critical subtasks, leading to task failure. However, we observed that a simple hybrid strategy that combines VLA with a rule-based controller can successfully perform the entire disassembly operation. These findings highlight the current limitations of VLA models in handling the dexterity and precision required for robotic EoL product disassembly. By offering a detailed analysis of the observed results, this study provides insights that may inform future research to address current challenges and advance end-to-end robotic automated disassembly.
Read the full abstract ▾
All authors Chang Liu, Sibo Tian, Sara Behdad, Xiao Liang, Minghui Zheng
Systems and Control
Quantum-Accelerated Deep Reinforcement Learning for Frequency Regulation Enhancement
Amin Masoumi and Mert Korkali
In modern power systems, frequency regulation is a fundamental prerequisite for ensuring system reliability and assessing the robustness of expansion projects. Conventional feedback control schemes, however, exhibit limited accuracy under varying operating conditions because their gains remain static. Consequently, deep reinforcement learning methods are increasingly employed to design adaptive controllers that can be generalized to diverse frequency control tasks. At the same time, recent advances in
quantum computing provide avenues for
embedding quantum capabilities into such critical applications. In particular, the potential of
quantum algorithms can be more effectively explored and harnessed on near-term
quantum devices by leveraging insights from active controller design. In this work, we incorporate a
quantum circuit together with an ansatz into the operation of a deep deterministic policy gradient
agent. The simulation results of the IEEE 14-bus test system demonstrate the potential of this integrated approach that can achieve reliable, robust performance across diverse real-world challenges.
Read the full abstract ▾
Signal Processing
Enabling Fast Polar SC Decoding with IR-HARQ
Marwan Jalaleddine, Mohamad Ali Jarkas, Jiajie Li et al. (+1 more)
To extend the applications of polar codes within next-generation wireless communication systems, it is essential to incorporate support for Incremental Redundancy (IR) Hybrid Automatic Repeat Request (HARQ) schemes. For very high-throughput applications, Successive Cancellation (SC) decoding is particularly appealing for polar codes owing to its high area efficiency. In this paper, we propose modifications to SC decoders that employ special nodes to accelerate decoding. Our modifications enable the use of polar IR-HARQ with SC decoding for high throughput applications. Compared to the unmodified SC IR-HARQ scheme, our proposed approach allows us to achieve a 72% reduction in node traversals with a polar code of length 2048. Simulation results confirm that the proposed special node modifications do not cause any degradation in FER performance.
Read the full abstract ▾
All authors Marwan Jalaleddine, Mohamad Ali Jarkas, Jiajie Li, Warren J. Gross
Systems and Control · Cross-listed from cs.SI
Distributed Articulation Point Identification in Time-Varying Undirected Networks
Xinye Xie, Ronghao Zheng, Senlin Zhang et al. (+1 more)
Identifying articulation points (APs) is fundamental to assessing the robustness of time-varying networks. In such dynamic environments, topological changes including edge additions and deletions can instantly alter the set of APs, demanding rapid and efficient re-assessment. This paper proposes a fully distributed
algorithm for identifying APs and monitoring biconnectivity. Our core contribution is an incremental update protocol. Unlike static methods that require global re-initialization which incurs high communication overhead, our
algorithm propagates information from the site of the change, updating only the affected nodes' state values. This approach, which builds upon a maximum consensus protocol, not only ensures convergence to the correct AP set following topological changes but also preserves network
privacy by preventing nodes from reconstructing the global
topology. We provide rigorous proofs of correctness for this eventual convergence and demonstrate its applicability and efficiency through experiments.
Read the full abstract ▾
All authors Xinye Xie, Ronghao Zheng, Senlin Zhang, Meiqin Liu
Signal Processing
Towards 6G Native-AI Edge Networks: A Semantic-Aware and Agentic Intelligence Paradigm
Chenyuan Feng, Anbang Zhang, Geyong Min et al. (+3 more)
The
evolution toward sixth-generation wireless systems positions intelligence as a native network capability, fundamentally transforming the design of
radio access networks (RANs). Within this
vision, Semantic-native communication and agentic intelligence are expected to play central roles. SemCom departs from bit-level fidelity and instead emphasizes task-oriented meaning exchange, enabling compact SC and introducing new performance measures such as semantic fidelity and task success rate. Agentic intelligence endows distributed RAN entities with goal-driven autonomy,
reasoning, planning, and multi-
agent collaboration, increasingly supported by foundation models and knowledge graphs. In this work, we first introduce the conceptual foundations of SemCom and agentic networking, and discuss why existing AI-driven O-RAN solutions remain largely bit-centric and task-siloed. We then present a unified taxonomy that organizes recent research along three axes: i) semantic abstraction level (symbol/feature/intent/knowledge), ii)
agent autonomy and coordination granularity (single-, multi-, and hierarchical-
agent), and iii) RAN control placement across PHY/MAC, near-real-time RIC, and non-real-time RIC. Based on this taxonomy, we systematically introduce enabling technologies including task-oriented semantic encoders/decoders, multi-
agent reinforcement learning, foundation-model-assisted RAN
agents, and knowledge-graph-based
reasoning for cross-layer awareness. Representative 6G use cases, such as immersive XR, vehicular V2X, and industrial digital twins, are analyzed to illustrate the semantic-agentic convergence in practice. Finally, we identify open challenges in semantic representation standardization, scalable trustworthy
agent coordination, O-RAN interoperability, and energy-efficient AI deployment, and outline research directions toward operational semantic-agentic AI-RAN.
Read the full abstract ▾
All authors Chenyuan Feng, Anbang Zhang, Geyong Min, Yongming Huang, Tony Q. S. Quek, Xiaohu You
Systems and Control
Probabilistic Dynamic Line Rating with Line Graph Convolutional LSTM
Minsoo Kim, Vladimir Dvorkin and Jip Kim
Dynamic line rating (DLR) is an effective approach to enhancing the utilization of existing transmission line infrastructure by adapting line ratings according to real-time weather conditions. Accurate DLR forecasts are essential for grid operators to effectively schedule generation, manage transmission congestion, and lower operating costs. As renewable generation becomes increasingly variable and weather-dependent, accurate DLR forecasts are also crucial for improving renewable utilization and reducing curtailment during congested periods. Deterministic forecasts, however, often inadequately represent actual line capacities under uncertain weather conditions, leading to operational risks and costly real-time adjustments. To overcome these limitations, we propose a novel network-wide probabilistic DLR
forecasting model that leverages both spatial and temporal information, significantly reducing the operational risks and inefficiencies inherent in deterministic methods. Case studies on a synthetic Texas 123-bus system demonstrate that the proposed method not only enhances grid reliability by effectively capturing true DLR values, but also substantially reduces operational costs.
Read the full abstract ▾
Signal Processing
RRAM-Based Analog Matrix Computing for Massive MIMO Signal Processing: A Review
Pushen Zuo and Zhong Sun
Resistive random-access
memory (RRAM) provides an excellent platform for analog
matrix computing (AMC), enabling both
matrix-vector multiplication (MVM) and the solution of
matrix equations through open-loop and closed-loop
circuit architectures. While RRAM-based AMC has been widely explored for accelerating neural networks, its application to signal processing in massive multiple-input multiple-output (
MIMO) wireless communication is rapidly emerging as a promising direction. In this Review, we summarize recent advances in applying AMC to massive
MIMO, including DFT/IDFT computation for OFDM modulation and demodulation using MVM
circuits;
MIMO detection and precoding using MVM-based iterative
algorithms; and rapid one-step solutions enabled by
matrix inversion (INV) and generalized inverse (GINV)
circuits. We also highlight additional opportunities, such as AMC-based compressed-sensing recovery for channel estimation and
eigenvalue circuits for leakage-based precoding. Finally, we outline key challenges, including RRAM device reliability, analog
circuit precision, array scalability, and data conversion bottlenecks, and discuss the opportunities for overcoming these barriers. With continued progress in device-
circuit-
algorithm co-design, RRAM-based AMC holds strong promise for delivering high-efficiency, high-reliability solutions to (ultra)massive
MIMO signal processing in the 6G era.
Read the full abstract ▾