Systems and Control · Cross-listed from math.OC
Isospectral Steering
Ralph Sabbagh and Tryphon T. Georgiou
We study the controllability of the differential Lyapunov equation under isospectral rotation of a linear gradient field. Specifically, control is effected by a symmetric time-varying gain-
matrix constrained to have fixed
eigenvalues; that is, by exclusively modulating the eigen-vectors of the state
matrix and not its
eigenvalues. Motivation for this problem stems from a certain type of control objectives (minimum shear/
attention) aimed to reduce anisotropic deformation when ensembles are steered by a common law–optimality necessitates constancy of
eigenvalues. In the paper we introduce and motivate this type of isospectral steering, and describe the reachable set of covariances for any specified terminal time and
eigenvalues of the gain
matrix. The theory we develop is intimately linked to multilinear
algebra as well as to positive linear
algebra and the Birkoff-von Neumann
theorem for doubly
stochastic matrices.
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Signal Processing
Fluid Antenna Enabled Compact Ultra Massive Antenna Array for Satellite Communications
Tianyu Han, Yongxu Zhu, Gan Zheng et al. (+1 more)
Satellites provide seamless coverage and are critical for emergency communications during natural disasters. However, their performance is constrained by limited spectrum and high deployment cost. To address these issues, we propose a fluid
antenna system (FAS)-based solution that enables dynamic signal adaptation. Building on this concept, a compact ultra-massive
antenna array (CUMA) is introduced, where multiple ports are simultaneously activated to coherently combine signal components. This design mitigates interference while reducing cost, as each fluid
antenna requires only a single RF chain yet achieves significant improvement in the received signal-to-interference-plus-noise ratio (SINR). We consider a satellite CUMA network where all ground users share the same satellite for uplink transmission, and CUMA is employed to suppress inter-user interference. Closed-form expressions for the received signal power, interference power, and their distributions are derived. Based on these results, the outage probability is obtained in a unified form along with an accurate approximation, and the ergodic rate is characterized. Our analysis identifies the conditions under which CUMA outperforms maximum ratio combining in satellite systems. Notably, with sufficiently compact fluid
antenna configurations, the received signal becomes deterministic, indicating that system performance is dominated by interference statistics. Moreover, increasing the number of ports yields a linear beamforming gain. Numerical results further compare orthogonal and non-orthogonal multiple access CUMA, showing that the latter achieves superior performance under wideband conditions.
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All authors Tianyu Han, Yongxu Zhu, Gan Zheng, Pantelis-Daniel Arapoglou
Signal Processing
Coordinated Multipoint Anti-jamming Beam Pattern Synthesis: From AI Accelerated Algorithm to Hardware Implementation
Zilong Wang, Cheng Zhang, Zhilei Zhang et al. (+3 more)
This paper presents a deep unfolding-supported coordinated multipoint beam pattern synthesis (DUCoMP-BPS) scheme to overcome the high complexity, poor adaptability, and limited scalability of traditional
cell-free anti-jamming beamforming. In the proposed design, access points (APs) independently determine analog beamforming using local angle information, while the central processing unit (CPU) performs cooperative digital beamforming with only a single AP-CPU interaction, significantly reducing fronthaul overhead. To further improve efficiency, a deep unfolding strategy transforms the costly step size search in analog beamforming into a trainable parameter, where an offline-trained complex-valued neural network enables fast and adaptive online inference. Simulation results show that the complexity of DUCoMP-BPS scales linearly with the number of APs, reduces single-AP analog beamforming runtime by about 67% compared to conventional optimization, and achieves superior nulling performance over purely data-driven approaches. Hardware feasibility is validated on an Advanced RISC Machine-Field Programmable Gate Array (ARM-FPGA) heterogeneous platform, where
algorithm-hardware co-verification and hardware-software decoupling enable efficient parallelism and low-latency execution. Finally, anechoic chamber measurements under practical hardware imperfections confirm robust beamforming performance, demonstrating the strong potential of DUCoMP-BPS for real-world deployment.
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All authors Zilong Wang, Cheng Zhang, Zhilei Zhang, Yaxuan Hu, Wen Wang, Yongming Huang
Systems and Control · Cross-listed from cs.RO
Cooptimizing Safety and Performance Using Safety Value-Constrained Model Predictive Control
Hao Wang, Nam Nguyen, Armand Jordana et al. (+2 more)
Autonomous systems are increasingly deployed in real-world environments, where they must achieve high performance while maintaining safety under state and input constraints. Although Model Predictive Control (MPC) provides a principled framework for constrained optimal control, guaranteeing safety beyond its finite planning horizon remains a fundamental challenge. In this work, we augment MPC with a safety value function-based terminal constraint that enforces membership in a control-invariant safe set at the end of each planning horizon. This formulation enables real-time synthesis of trajectories that are both high-performing and provably safe. We show that, under an exact safety value function and a feasible initialization, the proposed MPC scheme is recursively feasible, thereby ensuring persistent safety. In contrast to traditional terminal set constructions that rely on local linearizations or conservative approximations, our approach incorporates a reachability-based safety value function for terminal constraints, yielding less conservative and more expressive safety guarantees. We validate the proposed framework through simulation and hardware experiments on a Flexiv Rizon 10s manipulator. Results demonstrate improved constraint satisfaction and robustness compared to standard state-constrained MPC and reactive safety filtering, while maintaining competitive task performance. The full implementation and experiments are available on the project website.
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All authors Hao Wang, Nam Nguyen, Armand Jordana, Ludovic Righetti, Somil Bansal
Systems and Control · Cross-listed from cs.AR
Architectural Isolation as a Timing Safety Primitive for Edge AI Medical Devices: Controlled Experimental Evidence on a Shared-Silicon Platform
Akul Mallayya Swami
A system can satisfy accuracy-based validation, maintain output stability (Safety-Threshold Exceedance Rate, STER, equal to zero), and still violate timing constraints under deployment load. These are structurally independent properties that current pre-
market validation protocols often do not operationalize at the inference layer. This letter demonstrates their independence through a controlled same-hardware experiment: identical MobileNetV2 models are evaluated under identical
adversarial load on two execution paths of the same NVIDIA Jetson Orin Nano Super, a dedicated GPU accelerator (TensorRT FP16, half-precision floating point) and a general-purpose CPU (ONNX Runtime FP32, single-precision floating point). Both paths maintain STER = 0; the CPU path (ONNX Runtime FP32) degrades 7.2x under combined load (mean latency 9.8x higher than the GPU path (TensorRT FP16), which maintains latency below 11 ms), breaching the 10 Hz clinical cycle budget by 65%. Joint STER and latency verification is proposed as a candidate method for operationalizing U.S. FDA Draft Guidance FDA-2024-D-4488 robustness requirements at the inference layer, subject to regulatory review and clinical validation.
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Systems and Control
On the Generalization Properties of Selective State-Space Models for Filtering Tasks for Unknown Systems
Alex Tang, M. Emrullah Ildiz, Batin Kurt et al. (+2 more)
Selective State-Space Models (SSMs) such as Mamba have emerged as an alternative architecture to self-
attention based
transformers in sequence modeling tasks. Recent works have demonstrated the use of
transformers in some filtering and output prediction tasks via in-context learning. In this paper, we analyze whether structured SSMs can work equally well for filtering of unknown systems. In particular, we train the SSM on trajectory samples from a set of systems. At run-time, the SSM is given the outputs of an unknown system from the same set and is expected to predict the next output online. Theoretically, under appropriate assumptions, we derive generalization bounds as to why SSMs succeed in such tasks. Empirically, we demonstrate the performance via several numerical examples. We also discuss the advantages and disadvantages of SSMs versus
transformers for this task.
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All authors Alex Tang, M. Emrullah Ildiz, Batin Kurt, Samet Oymak, Necmiye Ozay
Systems and Control
An Individual-Delay-Reflected Generalized Consensus Analysis for Multi-Agent Systems with Heterogeneous Time-Varying Delays
Hye Jin Lee, Ho Sub Lee and PooGyeon Park
In multi-
agent systems, heterogeneous time delays exist for all
agents because of the difference in communication environments. Therefore, the consensus analysis of a system considering a homogeneous time-varying delay among all
agents results in conservatism. In this study, an individual-delay-reflected generalized consensus is proposed for multi-
agent systems with heterogeneous time-varying delays with various bounds. To reflect heterogeneous time-varying delays, the proposed Lyapunov-Krasovskii functional is constructed by dividing the integral term into intervals containing heterogeneous delays and considering augmented vectors with delay states and integral states. Furthermore, by adding zero equality conditions, conservatism is reduced. N-dependent generalized integral inequality is used to allow the user to adjust the computational complexity. Numerical examples demonstrate a reduction in conservatism with the proposed consensus criterion.
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Image and Video Processing · Cross-listed from cs.CV
ZID-Net: Zero-Inference Diffusion Prior Decoupling Network for Single Image Dehazing
Xinheng Li, Minghao Chen, Mengqing Wu et al. (+2 more)
Single image dehazing is often constrained by a trade-off between restoration quality and computational efficiency. While efficient, CNNs struggle to learn robust priors for dense and non-homogeneous haze. Conversely,
diffusion models provide strong generative priors but suffer from severe inference latency and sampling instability. To address these limitations, we propose ZID-Net, a novel framework that explicitly decouples
diffusion supervision from feed-forward inference. For efficient inference, we design a frequency-spatial decoupled feed-forward backbone. Within this backbone, a Channel-Spatial
Laplacian Mask (CSLM) filters haze-amplified noise to extract purified structural details, while Lightweight Global Context Blocks (LGCBs) establish long-range spatial dependencies to capture global haze variations. A Dynamic Feature Arbitration Block (DFAB) then adaptively fuses these semantic and structural features for robust reconstruction. To provide the backbone with degradation-aware priors without increasing inference cost, we introduce a Zero-Inference Prior Propagation Head (ZI-PPH) during training. ZI-PPH leverages a conditional
diffusion process to predict residual noise and regularize the shared representation. By discarding the
diffusion branch at test time, ZID-Net integrates the representation-shaping benefits of
diffusion supervision into a pure feed-forward architecture. Extensive experiments on synthetic, real-world, and remote-sensing
benchmarks demonstrate robust restoration across diverse haze conditions, with particularly strong performance on StateHaze1k, where ZID-Net achieves an average PSNR gain of 3.06 dB while maintaining efficient deterministic inference at 19.35 ms.
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All authors Xinheng Li, Minghao Chen, Mengqing Wu, Yan Liu, Guanying Huo
Systems and Control
Defining the Magnetization State of LCF Magnets: From Material Properties to Motor-Level Metrics
Taha El Hajji, Aleksandr Nadkin, Stefan Skoog et al. (+3 more)
Variable flux
memory motors, which employ Low Coercive Force (LCF) magnets, achieve extended high-efficiency operation through controllable magnetization states. To address the need for a unified approach to defining and comparing the magnetization state (MS) across material and motor levels, this paper proposes four MS definitions: two based on intrinsic material properties-
magnetic flux density B and
magnetic polarization J-and two based on motor-level quantities-fundamental flux linkage and back-EMF components. These definitions are evaluated across the id, iq operating plane using finite element analysis on an interior PMSM with a hybrid magnet configuration (LCF and HCF: High Coercive Force) and a defined
circuit setup. The results clarify the relationship between material-level behavior and measurable motor quantities. The proposed framework provides guidance for selecting appropriate MS metrics depending on the application objective, whether for material analysis, control implementation, or condition monitoring in variable flux machines.
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All authors Taha El Hajji, Aleksandr Nadkin, Stefan Skoog, Lars Sjöberg, Kristoffer Nilsson, Anthony C. Morcos
Systems and Control
Unified Energy Function Tailored to Inverter-Based Resources with PI Controllers for Transient Stability Analysis
Yifan Zhang, Hsiao-Dong Chiang, Yitong Li et al. (+1 more)
The increasing penetration of inverter-based resources (IBRs) has fundamentally altered the transient stability characteristics of modern power systems. IBRs typically rely on proportional–integral (PI) controllers for synchronization and regulation, resulting in nonlinear swing equations that differ significantly from those of synchronous generators (SGs) and exhibit state-dependent damping. Consequently, although the classical energy function is often adopted in IBR analysis by analogy with SGs, it cannot be directly applied to IBRs with PI controller. A new energy function explicitly tailored to PI controller is proposed in this letter. It admits a unified form and can be applied to a class of nonlinear systems with PI controllers. Two representative cases are considered, including a grid-following (GFL) inverter and a DC-voltage-controlled grid-forming (GFM) inverter, demonstrating less conservative and more effective estimation of the region of attraction (ROA). All findings are verified through hardware-in-the-loop (HIL) experiments.
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All authors Yifan Zhang, Hsiao-Dong Chiang, Yitong Li, Yang Wu
Systems and Control · Cross-listed from cs.RO
Real-Time Non-Contact Force Compensation for Wrist-Mounted Force/Torque Sensors in Haptic-Enabled Robotic Surgery Training
Walid Shaker and Mustafa Suphi Erden
Haptic feedback has been a long-missed feature in robotic-assisted surgery, one that would allow surgeons to perceive tissue properties and apply controlled forces during delicate procedures. Although commercial robotic systems have begun to integrate haptic technologies, their high costs limit accessibility for training and research purposes. To address this gap, we extend our previously developed low-cost robotic surgery training setup, RoboScope, by incorporating a wrist-mounted force/torque (F/T) sensor for haptic feedback training. Wrist-mounted sensing avoids many challenges associated with tip-mounted sensors but introduces additional non-contact forces, such as
gravity, sensor bias, installation offsets, and associated torques, which compromise measurement accuracy. In this paper, we propose a robust real-time compensation method based on recursive least squares (RLS). This method eliminates the need for
dataset collection and frequent recalibration while adapting to changing operating conditions. Experimental validation demonstrates that the proposed approach achieves over 95% error reduction in non-contact force compensation and more than 91% in non-contact torque compensation, significantly outperforming existing methods. These results highlight the potential of our approach for providing reliable haptic feedback in robotic surgery training and research.
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Signal Processing
Intention-Aware Semantic Agent Communications for AI Glasses
Peiwen Jiang, Fangyu Liu, Jiajia Guo et al. (+3 more)
Smart glasses are emerging as a promising interface between humans and artificial intelligence (AI)
agents, enabling first-person perception, contextual awareness, and real-time assistance. However, continuous offloading of visual data from wearable devices to cloud-based
vision-
language models (VLMs) is fundamentally constrained by limited wireless bandwidth and energy resources. This paper proposes an intention-aware semantic
agent communication framework for AI glasses, where data transmission is guided by user intention rather than raw pixel fidelity. In the proposed architecture, AI glasses act as an edge semantic
agent while a server-side VLM executes high-level cognition and
reasoning. The user intention can be inferred by the server-side VLM through the current transmitted content and the historical
prompts. Driven by specific user intentions, the glasses adaptively preserve textual content, document layout, or object semantics before transmission. We evaluate three representative scenarios with different lightweight preprocessing tools on the AI glasses. Simulation results demonstrate that intention-aware preprocessing significantly achieves more than 50% bandwidth reduction depending on the current task while maintaining task performance. Moreover, semantic transmission exhibits graceful degradation under low SNRs. The findings demonstrate that aligning communication resources with user intention is essential for robust and efficient wearable AI
agent systems.
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All authors Peiwen Jiang, Fangyu Liu, Jiajia Guo, Chao-Kai Wen, Shi Jin, Jun Zhang
Image and Video Processing
GS-DOT: Gaussian splatting-based image reconstruction for diffuse optical tomography
Jingjing Jiang
This work presents GS-DOT, a novel image reconstruction framework based on Gaussian Splatting (GS) for diffuse optical
tomography (DOT). Inspired by GS for rendering applications, absorption coefficients are represented as a sparse sum of anisotropic Gaussian primitives optimized to fit measured time-resolved point-spread functions through analytic gradients and Adam optimization. This is the first adaptation of GS
algorithms in the
photon diffusion regime, where the ray transport function is replaced by the
diffusion functions to enable accurate modeling of light transport in highly scattering media. Validation on synthetic tissue models demonstrate high accuracy in localization and quantification of reconstructed absorption maps for both clean and noisy signals. GS-DOT has demonstrated high robustness to noise and showed a huge reduction in
memory demand.
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Systems and Control · Cross-listed from cs.CR
An AI-Based Supervisory Measurement Integrity Validation Layer for Cyber-Resilient AC/DC Protection in Inverter-Based Microgrids
Ahmad Mohammad Saber, Ahmed Saber Refae, Davor Svetinovic et al. (+4 more)
Line current differential relays (LCDRs) are measurement-driven relays that rely on time-synchronized multi-phase current waveforms to infer internal faults in AC and DC power networks. In inverter-based microgrids, however, the increasing reliance on digitally communicated measurements exposes LCDRs to false-data injection attacks (FDIAs), in which adversaries manipulate remote measurement streams to create protection-triggering yet physically inconsistent current trajectories. This paper addresses this emerging measurement integrity problem by introducing a measurement integrity validation scheme that operates as a supervisory instrumentation layer for modern LCDRs. The proposed scheme interprets short windows of synchronized instantaneous current measurements recorded during relay operation and assesses their physical consistency to distinguish genuine fault-induced trajectories from cyber-manipulated measurement streams. A recurrent neural network is trained offline using only relay-available current measurements and exploits the temporal structure of differential current waveforms, which remains informative in inverter-dominated systems where current magnitude is no longer a reliable observable. The method requires no additional sensors, auxiliary protection elements, or prior knowledge of network
topology, and is applicable to both AC and DC LCDRs without structural modification. The proposed measurement validation scheme is evaluated on an islanded inverter-based microgrid under a comprehensive set of fault and FDIA scenarios, demonstrating high detection accuracy while preserving relay dependability. Hardware-in-the-loop validation using an OPAL-RT real-time simulator confirms that the scheme satisfies protection timing constraints and can operate in real time under realistic operating conditions.
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All authors Ahmad Mohammad Saber, Ahmed Saber Refae, Davor Svetinovic, Hatem Zeineldin, Amr Youssef, Ehab F. El-Saadany, Deepa Kundur
Signal Processing
Adaptive Plug-and-Play Channel Estimation with Consistency Models for MIMO Systems
Jinlong Li, Kexin Fang, Peng Yang et al. (+3 more)
This paper proposes a consistency-model-based channel estimation
algorithm for multiple-input multiple-output (
MIMO) systems. The proposed
algorithm employs a consistency model (CM) to learn the angle-domain channel distribution and uses the trained CM as a plug-and-play (PnP) generative prior for
MIMO channel estimation. The proposed
algorithm alternates between a pilot-observation-based data-consistency update and a CM-prior-based denoising update. In addition, the proposed
algorithm adaptively selects the penalty parameter according to residual energy and residual whiteness, and adjusts the CM denoising level according to the observed signal-to-noise ratio (SNR), thereby avoiding the performance degradation caused by fixed inference schedules under varying observation conditions. Simulation results show that the proposed
algorithm not only reduces the number of inference steps by 50%–90, but also achieves high estimation accuracy and favorable cross-
dataset performance.
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All authors Jinlong Li, Kexin Fang, Peng Yang, Zehui Xiong, Xianbin Cao, Dapeng Oliver Wu
Audio and Speech Processing · Cross-listed from cs.CV
Talker-T2AV: Joint Talking Audio-Video Generation with Autoregressive Diffusion Modeling
Zhen Ye, Xu Tan, Aoxiong Yin et al. (+8 more)
Joint audio-
video generation models have shown that unified generation yields stronger cross-modal coherence than cascaded approaches. However, existing models couple modalities throughout denoising via pervasive
attention, treating high-level semantics and low-level details in a fully entangled manner. This is suboptimal for talking head synthesis: while audio and facial motion are semantically correlated, their low-level realizations (acoustic signals and visual textures) follow distinct rendering processes. Enforcing joint modeling across all levels causes unnecessary
entanglement and reduces efficiency. We propose Talker-T2AV, an autoregressive
diffusion framework where high-level cross-modal modeling occurs in a shared backbone, while low-level refinement uses modality-specific decoders. A shared autoregressive
language model jointly reasons over audio and
video in a unified patch-level
token space. Two lightweight
diffusion transformer heads decode the hidden states into frame-level audio and
video latents. Experiments on talking portrait
benchmarks show Talker-T2AV outperforms dual-branch baselines in lip-sync accuracy,
video quality, and audio quality, achieving stronger cross-modal consistency than cascaded pipelines.
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All authors Zhen Ye, Xu Tan, Aoxiong Yin, Hongzhan Lin, Guangyan Zhang, Peiwen Sun, Yiming Li, Chi-Min Chan, Wei Ye, Shikun Zhang, Wei Xue
Systems and Control
Dynamic-Key Post-Quantum Encrypted Control Against System Identification Attacks
Jungjin Park and Kiminao Kogiso
This study proposes post-
quantum encrypted control systems based on dynamic-key Learning with Errors (LWE) encryption schemes. The proposed method develops update maps that simultaneously update the private key and ciphertexts within the LWE framework, enabling dynamic-key encrypted control resistant to system identification attacks. The growth of errors induced by homomorphic operations is analyzed, and sufficient parameter conditions guaranteeing correct decryption at each control step are clarified. Furthermore, a design procedure for the encrypted control systems is presented based on security metrics such as sample-identifying complexity and deciphering time. A numerical example demonstrates that the proposed control systems achieve secure control against the considered system identification attack.
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Signal Processing
Sparsity-Aware Event-Driven Impulse Radio Transceivers for Reliable Neuromorphic Inference
Zhengzhong Guan, Jiaying Li, Kanghua Li et al. (+2 more)
The growing number of Internet-of-Things (IoT) based artificial intelligence (AI) applications deployed at resource-constrained network edge call for ultra-reliable and low-latency data processing pipelines from distributed front-end sensors to remote inference units. Meanwhile,
brain-inspired neuromorphic computing featuring spiking neural networks (SNNs) have arisen as a new paradigm for energy-efficient AI inference. However, significant energy and time expenses incurred in high-complexity transceivers that combat fading and multi-user interference hinder implementations of multi-user neuromorphic inference for edge intelligence. To address this challenge, we consider in this paper a broadband multi-user remote inference system that integrates event-based sensing and time-hopping (TH) on-off keying (OOK) based ultra-wideband (UWB) communications for reliable neuromorphic inference. Specifically, we propose a novel two-timescale repetition coding that leverages intra-frame pulse sparsity for low-latency repetition. We also develop two neuromorphic inference schemes based on: (i) digital spike encoding that recovers each pixel of the event-frame by threshold-adaptive detection via an SNN based sparsity
estimator; and (ii) analog spike encoding that converts noisy correlator outputs at the receiver into analog-valued inputs for end-to-end (E2E) classification. Finally, numerical results validate the effectiveness of the proposed coding schemes, and reveal a signal-to-noise ratio (SNR)-dependent performance crossover between the two inference schemes, indicating that analog spike encoding based schemes are preferable with mild or high SNR while digital spike encoding based schemes remain robust in low SNR regime.
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All authors Zhengzhong Guan, Jiaying Li, Kanghua Li, Bojun Cheng, Hong Xing
Signal Processing
PILOT: One Physics-Integrated Generation Framework to Unify 2D and 3D Radio Map Construction
Weiming Huang, Hao Sun and Junting Chen
Unified 2D and 3D
radio map construction supports network planning, wireless digital twins, and unmanned aerial vehicle (
UAV) applications. In urban environments, blockage, reflection, and diffraction make accurate construction expensive for physics-based solvers. Autoregressive next-
token prediction offers a single sequential formulation that can cover both 2D and 3D generation, but standard raster ordering ignores the spatial structure of
radio propagation. When generation follows propagation, each
token is predicted from propagation-relevant history rather than spatially arbitrary context, which provides more causally informative conditioning and lowers conditional uncertainty. We propose PILOT, a pretrained autoregressive framework that replaces raster scan with a wavefront sequence expanding outward from the transmitter. Each prediction step is guided by an environment-aware instruction that spatially aligns environment features with the queried
radio map region. The same framework extends to 3D
radio maps through height-slice stacking while a gradient loss enforces vertical continuity. On standard 2D
benchmarks, PILOT achieves the lowest NMSE among all baselines. For volumetric generation, it reduces NMSE by 78% relative to the
diffusion baseline at roughly $2500\times$ faster inference. It also outperforms methods that rely on 10% sparse measurements and achieves the best zero-shot results in the cross-domain evaluation.
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Signal Processing
Signal Processing Foundations of Reconfigurable Antennas in the Tri-Hybrid MIMO Architecture
Nitish Vikas Deshpande, Joseph Carlson, Siyun Yang et al. (+6 more)
To enable larger apertures in multipleinput multipleoutput
MIMO systems the trihybrid
MIMO architecture offers a promising lowcost and lowpower solution by introducing reconfigurable
antennas as a third layer of precoding on top of conventional digital and analog processing In this paper we develop a unified signal processing framework for trihybrid
MIMO that explicitly captures the electromagnetic EM characteristics of diverse reconfigurable
antenna technologies We first propose a generic inputoutput model that incorporates the reconfigurable
antenna layer into an effective channel representation revealing a fundamental coupling between the channel precoder and radiated power Building on this model we formulate a general optimization problem that jointly accounts for digital analog and antennadomain precoding under hardware and power constraints We then instantiate this framework across seven representative reconfigurable
antenna architectures including parasitic arrays dynamic metasurface
antennas fluidpixel
antennas polarizationreconfigurable
antennas stacked intelligent metasurfaces pinching
antenna systems and nonradiating wires To systematically compare these heterogeneous architectures we introduce a new metric the reconfigurability efficiency factor REF which quantifies the performance gains achievable through
antenna reconfiguration under realistic constraints Numerical results demonstrate the tradeoffs among aperture size power consumption hardware complexity and spectral efficiency Our results establish that EMlevel reconfiguration reshapes the signal processing design space highlighting the need for new architectures and
algorithms that jointly optimize across digital analog and electromagnetic domains This work reveals that electromagnetic reconfiguration couples the channel and precoder
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All authors Nitish Vikas Deshpande, Joseph Carlson, Siyun Yang, Mohamed Akrout, Alfredo Gonzalez, Miguel Rodrigo Castellanos, Tharmalingam Ratnarajah, Chan-Byoung Chae, Robert W. Heath Jr
Systems and Control
Physics-Aware LLM-Based Probabilistic Wind Power Scenario Generation under Extreme Icing Conditions
Lei Wang, Ying Zhang, Di Shi et al. (+1 more)
Accurately characterizing wind power uncertainty under icing and post-disaster conditions remains a critical challenge for resilient power system operation. To address this issue, this paper proposes a physics-aware large
language model (LLM) framework for probabilistic wind power scenario generation under extreme icing conditions. The proposed framework integrates supervisory control and data acquisition (SCADA)-based physical modeling,
multimodal tokenization, and a causal
Transformer architecture trained in an autoregressive manner. A physics-aware decoding scheme effectively enforces rated power limits and ramping constraints on the generated trajectories while preserving
stochastic diversity. Case studies using real wind turbine data show that the proposed method reproduces icing-induced power degradation and temporal variability observed during extreme weather. The resulting scenarios are physically consistent and high-fidelity, thereby significantly enhancing resilience assessment and recovery planning in renewable-integrated power systems.
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All authors Lei Wang, Ying Zhang, Di Shi, Fei Ding
Systems and Control
Resource-Constrained Shortest Path with Polytopic Reset Sets
Khaled Surur and Melkior Ornik
This paper investigates the problem of computing the shortest path between two states under resource constraints in environments with resource-replenishment regions. Namely, the length of the path is limited by a budget that can be restored within polytopic replenishment regions. We show that the optimal path in this problem exhibits a distinct
geometric structure: it consists of straight-line segments, changes direction at the edges of replenishment regions, and enters a sequence of replenishment regions in a feasible-connected space. We propose an approach to solve the continuous problem in two steps: using a graph-based approach, followed by convex programming. First, we define a graph whose nodes are possible waypoints of feasible paths, and the edges are the Euclidean distances between these nodes. To obtain a discrete set of nodes that ensure a feasible and near-optimal solution, we utilize a wavefront
algorithm. With a sufficiently small spacing between wavefronts, the solution of the shortest path problem on this graph yields the optimal sequence of polytopes to visit. Next, we use convex optimization on this sequence of polytopes to refine the solution to optimality. A numerical experiment is presented to demonstrate the effectiveness of the approach.
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