Audio and Speech Processing · Cross-listed from cs.CL
RECOVER: Robust Entity Correction via agentic Orchestration of hypothesis Variants for Evidence-based Recovery
Abhishek Kumar and Aashraya Sachdeva
Entity recognition in Automatic
Speech Recognition (ASR) is challenging for rare and domain-specific terms. In domains such as finance, medicine, and air traffic control, these errors are costly. If the entities are entirely absent from the ASR output, post-ASR correction becomes difficult. To address this, we introduce RECOVER, an agentic correction framework that serves as a tool-using
agent. It leverages multiple hypotheses as evidence from ASR, retrieves relevant entities, and applies Large
Language Model (LLM) correction under constraints. The hypotheses are used using different strategies, namely, 1-Best, Entity-Aware Select, Recognizer Output Voting Error Reduction (ROVER) Ensemble, and LLM-Select. Evaluated across five diverse
datasets, it achieves 8-46% relative reductions in entity-phrase word error rate (E-WER) and increases recall by up to 22 percentage points. The LLM-Select achieves the best overall performance in entity correction while maintaining overall WER.
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Signal Processing
Near-Field Wideband Localization using TTD-Based Terahertz Extremely Large-Scale Arrays
Qianyu Yang, Haiyang Zhang, Francesco Guidi et al. (+4 more)
The synergy between extremely large-scale
antenna arrays and terahertz technology in sixth-generation networks establishes a near-field wideband transmission environment, enabling the generation of highly focused beams. To leverage this capability for multi-source localization, we propose a direct localization method based on the
curvature-of-arrival of spherical wavefronts for estimating the positions of multiple near-field users from wideband signals. Furthermore, to overcome the spatial-wideband effect, we introduce a hybrid analog/digital array architecture with true-timedelayers (TTDs). We derive a closed-form position error bound to characterize the fundamental estimation performance and optimize the analog coefficients of array by maximizing the trace of the Fisher information
matrix to minimize this bound. Furthermore, we extend this method to a sub-optimal iterative method that jointly optimizes beam focusing and localization, without requiring prior knowledge of the source positions for array design. Simulation results show that the proposed array configuration design significantly enhances the performance of near-field wideband localization, while the presence of TTDs effectively mitigates the localization performance degradation caused by spatial-wideband effects.
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All authors Qianyu Yang, Haiyang Zhang, Francesco Guidi, Anna Guerra, Davide Dardari, Baoyun Wang, Yonina C. Eldar
Signal Processing
Identifiability in Blind Source Separation through Stabilizer Shrinkage: Unifying Non-Gaussianity and Observation Diversity
Tomomi Ogawa and Hiroki Matsumoto
Identifiability is a central issue in blind source separation (BSS), determining whether latent sources can be uniquely recovered from observed mixtures. Classical approaches address identifiability either by exploiting source non-Gaussianity via higher-order statistics (HOS) or by enriching the observation structure through temporal, spatial, or multi-channel diversity using second-order statistics (SOS), and these routes are often regarded as fundamentally different. In this paper, we revisit identifiability in BSS from a structural perspective, interpreting it as constraint-induced reduction of residual ambiguity in the mixing model. Within this framework, the observation mechanism is viewed broadly to include both input-side statistical constraints and output-side observation structures. HOS-based and SOS-based approaches are then unified as mechanisms of stabilizer shrinkage, in which observation-induced constraints reduce an initially continuous ambiguity to a finite residual one. To connect this structural viewpoint with finite-sample regimes, we introduce a Jacobian-based sensitivity probe as a numerical diagnostic of local identifiability. Numerical experiments show that increasing non-Gaussianity or observation diversity suppresses the same residual
symmetry, revealing a structural trade-off between source statistics and observation design. These results provide a unified interpretation of classical BSS methods and clarify how observation constraints govern identifiability.
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Signal Processing
Robust High Mobility NLOS UE Beamforming Strategy for Gigantic MIMO
Josep R. Fernández Rull, Liang Liu, Henrik Sjöland et al. (+1 more)
Maintaining robust and stable communication links in high-mobility scenarios is challenging for time-division duplex (TDD) reciprocity-based gigantic
MIMO systems due to rapid channel variations, especially in non-line-of-sight (NLOS) conditions. This paper proposes a user equipment (UE) beamforming strategy that enables reliable links in high mobility without additional pilot overhead. The proposed strategy aligns the UE beamforming direction with the travel axis. Our analysis shows that this choice minimizes the Doppler spread of the channel, resulting in improved temporal stability. We evaluate this approach through simulations in scattering-rich environments representative of gigantic
MIMO deployments. Numerical results confirm that movement-aligned UE beamforming enhances link robustness, increases achievable data rates, and reduces pilot signaling requirements, thereby lowering UE power consumption. These findings indicate that travel-axis-aligned UE beamforming is a promising method for improving reliability in future high-mobility wireless systems.
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All authors Josep R. Fernández Rull, Liang Liu, Henrik Sjöland, Juan Vidal Alegría
Audio and Speech Processing · Cross-listed from cs.SD
CAST-TTS: A Simple Cross-Attention Framework for Unified Timbre Control in TTS
Zihao Zheng, Wen Wu, Chao Zhang et al. (+2 more)
Current Text-to-
Speech (TTS) systems typically use separate models for
speech-prompted and text-prompted timbre control. While unifying both control signals into a single model is desirable, the challenge of cross-modal
alignment often results in overly complex architectures and training objective. To address this challenge, we propose CAST-TTS, a simple yet effective framework for unified timbre control. Features are extracted from
speech prompts and text
prompts using pre-trained encoders. The multi-stage training strategy efficiently aligns the
speech and projected text representations within a shared
embedding space. A single cross-
attention mechanism then allows the model to use either of these representations to control the timbre. Extensive experiments validate that the unified cross-
attention mechanism is critical for achieving high-quality synthesis. CAST-TTS achieves performance comparable to specialized single-input models while operating within a unified architecture. The demo page can be accessed at https://HiRookie9.github.io/CAST-TTS-Page.
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All authors Zihao Zheng, Wen Wu, Chao Zhang, Mengyue Wu, Xuenan Xu
Audio and Speech Processing
Speakers Localization Using Batch EM In Unfolding Neural Network
Rina Veler and Sharon Gannot
We propose an interpretable Batch-EM Unfolded Network for robust speaker localization. By
embedding the iterative EM procedure within an encoder-EM-decoder architecture, the method mitigates initialization sensitivity and improves convergence. Experiments show superior accuracy and robustness over the classical Batch-EM in reverberant conditions.
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Signal Processing
Efficient 2.5-D FEM-Based Scattering Analysis of the Human Body for RF Sensing
Haoqing Wen, Michele D'Amico, Matteo Oldoni et al. (+5 more)
Model training for Device-Free Localization (DFL) and
Radio-Frequency (RF) sensing heavily relies on large-scale
datasets, which are difficult, expensive, and time-consuming to obtain through measurements. This paper proposes a fast 2.5-dimensional Finite Element Method (2.5-D FEM) for computing the scattering fields of a Body of Revolution (BoR) human model under the excitation of a z-directed dipole. The proposed method can evaluate the effect of human micro-movements through the statistical characteristics of the Received Signal Strength Indicator (RSSI). The numerical accuracy and the practical applicability of the proposed method are validated through comparisons with full-wave simulations and indoor RF sensing experiments. The simulation results show agreement with the experimental measurements, demonstrating that the method is a reliable tool for evaluating micro-movement-induced statistical variations. The proposed method provides a practical and efficient means for generating large-scale, labeled RF training
datasets, thereby accelerating the development of indoor localization tools as well as the calibration and tuning of tomographic reconstruction methods.
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All authors Haoqing Wen, Michele D'Amico, Matteo Oldoni, Federica Fieramosca, Vittorio Rampa, Stefano Savazzi, Qi Wu, Gian Guido Gentili
Signal Processing
Physics-Informed Spatial-Temporal Transformer for Terahertz Near-Field Beam Tracking
Zhi Zeng, Chong Han and Emil Björnson
Terahertz (THz) ultra-massive multiple-input multiple-output (UM-
MIMO) promises ultra-high throughput, while its highly directional beams demand rapid and accurate beam tracking driven by precise user-state estimation. Moreover, large array apertures at high frequencies induce near-field propagation effects, where far-field modeling becomes inaccurate and near-field parametric channel estimation is costly. Bypassing near-field codebook, PAST-TT is proposed to bridge near-field tracking with low-overhead far-field codebook probing by exploiting parallax, amplified by widely spaced subarrays. With comb-type frequency-division multiplexing pilots, each subarray yields frequency-affine phase signatures whose frequency and temporal increments encode propagation delay and its variation between frames. Building on these signatures, a Parallax-Aware Spatial
Transformer (PAST) compresses them and outputs per-frame position estimates with
token reliability to downweight bad frames, regularized by a physics-in-the-loop consistency loss. A causal Temporal
Transformer (TT) then performs reliability-aware filtering and prediction over a sliding window to initialize the beam of the next frame. Acting on short
token sequences, PAST-TT avoids a monolithic spatial-temporal network over raw pilots, which keeps the model lightweight with a critical path latency of 0.61 ms. Simulations show that at 15 dB signal-to-noise ratio, PAST achieves 7.81 mm distance RMSE and 0.0588{\deg} angle RMSE. Even with a bad-frame rate of 0.1, TT reduces the distance and angle prediction RMSE by 23.1% and 32.8% compared with the best competing tracker.
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Signal Processing
Signal Recovery from Time and Frequency Samples
Mert Kayaalp and Oleg Szehr
We analyze signal recovery when samples are taken concomitantly from a signal and its
Fourier transform. This two-sided sampling framework extends classical one-sided reconstruction and is particularly useful when measurements in either domain alone are insufficient because of sensing, storage, or bandwidth constraints. We formulate the resulting recovery problem in finite-dimensional spaces and reproducing kernel
Hilbert spaces, and illustrate the infinite-dimensional setting in a
Fourier-symmetric Sobolev space. Numerical experiments with sinc- and Hermite-based schemes indicate that, under a fixed sampling budget, two-sided sampling often yields better conditioned systems than one-sided approaches. A simplified spectrum-monitoring example further demonstrates improved reconstruction when limited time samples are supplemented with frequency-domain information.
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Systems and Control · Cross-listed from math.OC
Featurized Occupation Measures for Structured Global Search in Numerical Optimal Control
Qi Wei, Jianfeng Tao, Haoyang Tan et al. (+1 more)
Numerical optimal control is split between globally structured but dimensionally intractable Hamilton–Jacobi–Bellman (HJB) methods and scalable but local trajectory optimization. We introduce Featurized Occupation Measures (FOM), a finite-dimensional primal–dual interface where HJB subsolutions guide primal search and primal occupation data can inform certificate refinement. Explicit and implicit realizations, based on finite Liouville tests and rollout-sampled residuals, are proved asymptotically consistent with the exact occupation-measure LP. FOM also identifies when HJB-type certificates avoid full state-space representation. For factor graphs induced by compatible passivity-based interconnections, blockwise HJB inequalities yield block-additive OM-dual certificates, including blockwise approximate variants. The curse of dimensionality is then shifted from state dimension to interconnection
topology. Approximate certificates remain reusable under time shifts and bounded model perturbations, with explicit degradation bounds. A static obstacle-avoidance
benchmark illustrates how tighter certificates improve sample-based global search.
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All authors Qi Wei, Jianfeng Tao, Haoyang Tan, Hongyu Nie
Signal Processing
Performance Analysis of Flexible Duplex Inter-Satellite Links in LEO Networks
Yomali Lokugama, Charith Dissanayake, Saman Atapattu et al. (+1 more)
This paper investigates energy-efficient inter-satellite communication in Low Earth Orbit (LEO) networks, where satellites exchange both buffered and newly generated data through half-duplex inter-satellite links (ISLs). Due to orbital motion and interference-prone directional asymmetry, the achievable ISL capacities in opposite directions vary dynamically, leading to inefficient utilization under conventional fixed or alternating duplex modes. To address this, we propose a Flexible Duplex (FlexD) scheme that adaptively selects the ISL transmission direction in each slot to maximize instantaneous end-to-end sky-to-ground throughput, jointly accounting for ISL quality, downlink conditions, and queue backlogs. A unified analytical framework is developed that transforms the bottleneck rate structure into an equivalent SINR domain, enabling closed-form derivations of throughput outage probability and energy efficiency under deterministic ISLs and Rician satellite-to-ground fading. The analysis reveals distinct operating regions governed by ISL and backlog constraints and provides tractable bounds for ergodic rate and energy efficiency. Numerical results confirm that FlexD achieves higher reliability and up to 30% improvement in energy efficiency compared with conventional half- and full-duplex schemes under realistic inter-satellite interference conditions.
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All authors Yomali Lokugama, Charith Dissanayake, Saman Atapattu, Kandeepan Sithamparanathan
Audio and Speech Processing
Robust Generative Audio Quality Assessment: Disentangling Quality from Spurious Correlations
Kuan-Tang Huang, Chien-Chun Wang, Cheng-Yeh Yang et al. (+3 more)
The rapid proliferation of AI-Generated Content (AIGC) has necessitated robust metrics for perceptual quality assessment. However, automatic Mean Opinion Score (MOS) prediction models are often compromised by data scarcity, predisposing them to learn spurious correlations– such as
dataset-specific acoustic signatures– rather than generalized quality features. To address this, we leverage domain
adversarial training (DAT) to disentangle true quality perception from these nuisance factors. Unlike prior works that rely on static domain priors, we systematically investigate domain definition strategies ranging from explicit metadata-driven labels to implicit data-driven clusters. Our findings reveal that there is no "one-size-fits-all" domain definition; instead, the optimal strategy is highly dependent on the specific MOS aspect being evaluated. Experimental results demonstrate that our aspect-specific domain strategy effectively mitigates acoustic biases, significantly improving correlation with human ratings and achieving superior generalization on unseen generative scenarios.
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All authors Kuan-Tang Huang, Chien-Chun Wang, Cheng-Yeh Yang, Hung-Shin Lee, Hsin-Min Wang, Berlin Chen
Systems and Control · Cross-listed from math.OC
Decentralized design of leader-following consensus protocols for asymmetric matrix-weighted heterogeneous multiagent systems
Lanhao Zhao and Yangzhou Chen
This paper investigates a decentralized design approach of leader-following consensus protocols for heterogeneous multiagent systems under a fixed communication
topology with a directed spanning tree (DST) and asymmetric weight
matrix. First, a control protocol using only the information of the neighbor on the DST of each
agent is designed, which is called the consensus protocol with minimal communication links. Particularly, the DST-based linear transformation method is used to transform the consensus problem into a partial variable stability problem of a corresponding system, and a decentralized design method is proposed to find the gain
matrices in the protocols. Next, the decentralized design approach is extended to the protocols using all neighbor information in the original communication
topology with the help of the
matrix diagonally dominant method. Some numerical simulations are given to illustrate the theoretical results.
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Systems and Control · Cross-listed from math.OC
Decentralized design of consensus protocols with minimal communication links based on directed spanning tree
Yangzhou Chen and Lanhao Zhao
This paper proposes a decentralized design approach of consensus protocols of multi-
agent systems via a directed-spanning-tree(DST)-based linear transformation and the corresponding minimal communication links. First, the consensus problem of multi-
agent systems is transformed into the decentralized output stabilization problem by constructing a linear transformation based on a DST of the communication
topology, and thus a necessary and sufficient consensus criterion in terms of decentralized fixed mode is derived. Next, a new distributed protocol is designed by using only the neighbors information on the DST, which is a fully decentralized design approach. Finally, some numerical examples are given to verify the results attained.
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Systems and Control · Cross-listed from stat.ML
Deep Adaptive Model-Based Design of Experiments
Arno Strouwen and Sebastian Micluţa-Câmpeanu
Model-based design of experiments (MBDOE) is essential for efficient parameter estimation in nonlinear dynamical systems. However, conventional adaptive MBDOE requires costly posterior inference and design optimization between each experimental step, precluding real-time applications. We address this by combining Deep Adaptive Design (DAD), which amortizes sequential design into a neural network policy trained offline, with differentiable mechanistic models. For dynamical systems with known governing equations but uncertain parameters, we extend sequential contrastive training objectives to handle nuisance parameters and propose a
transformer-based policy architecture that respects the temporal structure of dynamical systems. We demonstrate the approach on four systems of increasing complexity: a fed-batch bioreactor with Monod kinetics, a Haldane bioreactor with uncertain substrate inhibition, a two-compartment pharmacokinetic model with nuisance clearance parameters, and a DC motor for real-time deployment.
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Signal Processing
Structure-Aware Multimodal LLM Framework for Trustworthy Near-Field Beam Prediction
Mengyuan Li, Qianfan Lu, Jiachen Tian et al. (+5 more)
In near-field extremely large-scale multiple-input multiple-output (XL-
MIMO) systems, spherical wavefront propagation expands the traditional beam codebook into the joint angular-distance domain, rendering conventional beam training prohibitively inefficient, especially in complex 3-dimensional (3D) low-altitude environments. Furthermore, since near-field beam variations are deeply coupled not only with user positions but also with the physical surroundings, precise beam
alignment demands profound environmental understanding capabilities. To address this, we propose a large
language model (LLM)-driven
multimodal framework that fuses historical GPS data, RGB image,
LiDAR data, and strategically designed task-specific textual
prompts. By utilizing the powerful emergent
reasoning and generalization capabilities of the LLM, our approach learns complex spatial dynamics to achieve superior environmental comprehension...
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All authors Mengyuan Li, Qianfan Lu, Jiachen Tian, Hongjun Hu, Yu Han, Xiao Li, Chao-kai Wen, Shi Jin
Signal Processing
Wireless Digital Twin Calibration: Refining DFT-Domain Channel Information
Hao Luo, Saeed R. Khosravirad and Ahmed Alkhateeb
Wireless digital twins can be leveraged to provide site-specific synthetic channel information through precise physical modeling and signal propagation simulations. This can help reduce the overhead of channel state information (CSI) acquisition, particularly needed for large-scale
MIMO systems. For high-quality digital twin channels, the classical approach is to increase the digital twin fidelity via more accurate modeling of the environment, propagation, and hardware. This, however, comes with high computational cost, making it unsuitable for real-time applications. In this paper, we propose a new framework that, instead of calibrating the digital twin model itself, calibrates the DFT-domain channel information to reduce the gap between the low-fidelity digital twin and its high-fidelity counterpart or the real world. This allows systems to leverage a low-complexity digital twin for generating real-time channel information without compromising quality. To evaluate the effectiveness of the proposed approach, we adopt codebook-based CSI feedback as a case study, where refined synthetic channel information is used to identify the most relevant DFT codewords for each user. Simulation results demonstrate the effectiveness of the proposed digital twin calibration approach in achieving high CSI acquisition accuracy while reducing the computational overhead of the digital twin. This paves the way for realizing digital twin assisted wireless systems.
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Signal Processing
Knowledge Distillation for Collaborative Learning in Distributed Communications and Sensing
Nhan Thanh Nguyen, Mengyuan Ma, Nir Shlezinger et al. (+4 more)
The rise of sixth generation (6G) wireless networks promises to deliver ultra-reliable, low-latency, and energy-efficient communications, sensing, and computing. However, traditional centralized artificial intelligence (AI) paradigms are ill-suited to the decentralized, resource-constrained, and dynamic nature of 6G ecosystems. This paper explores knowledge
distillation (KD) and collaborative learning as promising techniques that enable the efficient and scalable deployment of lightweight AI models across distributed communications and sensing (C&S) nodes. We begin by providing an overview of KD and highlight the key strengths that make it particularly effective in distributed scenarios characterized by device heterogeneity, task diversity, and constrained resources. We then examine its role in fostering collective intelligence through collaborative learning between the central and distributed nodes via various knowledge distilling and deployment strategies. Finally, we present a systematic numerical study demonstrating that KD-empowered collaborative learning can effectively support lightweight AI models for multi-modal sensing-assisted beam tracking applications with substantial performance gains and complexity reduction.
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All authors Nhan Thanh Nguyen, Mengyuan Ma, Nir Shlezinger, Junil Choi, Yonina C. Eldar, A. Lee Swindlehurst, Markku Juntti
Systems and Control
Constrained Feedback Control of Nonlinear Systems via Approximate HJB and Control Barrier Functions
Milad Alipour Shahraki and Laurent Lessard
This paper presents a two-stage framework for constrained feedback control of input-affine nonlinear systems. Offline, an approximate value function for the unconstrained problem is computed, for example using Hamilton–Jacobi–Bellman (HJB)-based policy iteration. Online, the proposed quadratic program (QP) minimizes the pre-
Hamiltonian evaluated using the approximate value-function gradient subject to safety constraints enforced by control barrier functions (CBFs). This architecture decouples performance optimization from constraint enforcement, allowing constraints to be modified without recomputing the value function. As in CBF-QP architectures based on control Lyapunov functions (CLFs), safety is enforced as a hard constraint; however, the performance objective targets approximate optimality rather than a prescribed Lyapunov decay. Numerical results on a linear 2-state hovercraft and a nonlinear 9-state spacecraft attitude-control problem show agreement with the constrained open-loop optimal control problem (OCP)
benchmark in the linear case, and performance close to the OCP
benchmark, improving on CLF-based controllers, in the nonlinear case.
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Signal Processing
RSMA-Assisted Multi-Functional 6G: Integrated Sensing, Communication, and Powering
Xiaoxuan Jiang and Yijie Mao
Integrated sensing, communication, and powering (ISCAP) has emerged as a promising solution for enabling multi-functionality in 6G networks. However, it poses a significant challenge in the design of multi-functional waveforms that must jointly consider communication, sensing, and powering performance. In this paper, we propose a novel rate-splitting multiple access (RSMA)-enabled multi-functional ISCAP network, where RSMA facilitates the use of communication signals to simultaneously achieve all three functionalities. Based on the proposed system model, we investigate the beamforming optimization problem to explore the performance trade-offs among communication, sensing, and power transfer. To efficiently solve this problem, we develop a novel ISCAP-extragradient (ISCAP-EG)
algorithm, which transforms the original problem into a sequence of convex subproblems, reformulates the dual problem as a variational inequality, and solves it using the EG method. Numerical results show that the proposed ISCAP-EG
algorithm achieves performance equivalent to that of the conventional successive convex approximation (SCA)-based method, while significantly reducing simulation time. Moreover, the RSMA-enabled multi-functional ISCAP network enhance the performance trade-off compared with the conventional space-division multiple access (SDMA)-based scheme, highlighting RSMA as a promising technique for advancing multi-functional ISCAP development in 6G.
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Signal Processing
Near-Field Localization via Reconfigurable Antennas
Alireza Fadakar, Yuchen Zhang, Hui Chen et al. (+3 more)
Reconfigurable
antennas (RAs) utilize the electromagnetic (EM) domain to provide dynamic control over
antenna radiation patterns, which offers an effective way to enhance power efficiency in wireless links. Unlike conventional arrays with fixed element patterns, RAs enable on-demand beam-pattern synthesis by directly controlling each
antenna's EM characteristics. While existing research on RAs has primarily focused on improving spectral efficiency, this paper explores their application for downlink localization. Moreover, the majority of existing works focus on far-field scenarios with little
attention on near-field (NF). Motivated by these gaps, we consider a synthesis model in which each
antenna generates desired beampatterns from a finite set of EM basis functions. We then formulate a joint optimization problem for the baseband (BB) and EM precoders with the objective of minimizing the user equipment (UE) position error bound (PEB) in NF conditions. Our analytical derivations and extensive simulation results demonstrate that the proposed hybrid precoder design for RAs significantly improves UE positioning accuracy compared to traditional non-reconfigurable arrays.
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All authors Alireza Fadakar, Yuchen Zhang, Hui Chen, Musa Furkan Keskin, Henk Wymeersch, Andreas F. Molisch
Systems and Control
Finite Boundary-Layer Residence Certificates for Non-Strict Control Barrier Functions
Tianyu Han, Guangwei Wang and Bo Wang
Non-strict control barrier function (CBF) conditions guarantee safety through forward invariance, but they do not preclude trajectories from remaining near the safe-set boundary for extended continuous time intervals. This paper develops a finite boundary-layer residence certificate for such settings. The certificate preserves the standard non-strict CBF safety condition and uses a bounded auxiliary function whose derivative is bounded away from zero in a prescribed boundary layer, yielding an explicit upper bound on every uninterrupted residence interval. For control-affine systems, a selected auxiliary branch is implemented as an additional affine constraint in a CBF-QP, and a tangential-input compatibility condition is given to ensure simultaneous feasibility with the hard CBF constraint for unconstrained inputs. A local-chart version handles angular or multi-valued auxiliary functions such as $\operatorname{atan2}$. Single-integrator, double-integrator, and nonholonomic unicycle examples illustrate the resulting radial–tangential construction and its local-chart and feasibility limitations.
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Signal Processing
Implicit Neural Representation for Multiuser Continuous Aperture Array Beamforming
Shiyong Chen, Shengqian Han and Jia Guo
This paper studies the optimization of beamforming functions for multiuser multi-continuous aperture array (CAPA) systems, where both the base station and the users are equipped with CAPAs. We first derive a closed-form expression for the achievable sum rate, and then develop a functional weighted minimum mean-squared error (WMMSE)
algorithm, which transforms the functional optimization problem into an equivalent parameter optimization problem by employing orthonormal basis expansion. Based on the functional WMMSE
algorithm, we further propose BeamINR, an implicit neural representation (INR) method for learning continuous beamforming functions. BeamINR is designed as a graph neural network to exploit the permutation equivariance of the optimal beamforming policy, with an update equation designed according to the functional WMMSE iterations. Simulation results show that both the functional WMMSE
algorithm and BeamINR outperform existing numerical and INR-based baselines. BeamINR approaches the sum rate of the functional WMMSE with substantially lower inference latency. Compared with INR-based baselines, BeamINR reduces training complexity and improves generalization to the number of users, CAPA sizes, and carrier~frequencies.
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Image and Video Processing · Cross-listed from cs.RO
The Era of End-to-End Autonomy: Transitioning from Rule-Based Driving to Large Driving Models
Eduardo Nebot and Julie Stephany Berrio Perez
Autonomous driving is undergoing a shift from modular rule based pipelines toward end to end (E2E) learning systems. This paper examines this transition by tracing the
evolution from classical sense perceive plan control architectures to large driving models (LDMs) capable of mapping raw sensor input directly to driving actions. We analyze recent developments including Tesla's Full Self Driving (FSD) V12 V14, Rivian's Unified Intelligence platform, NVIDIA Cosmos, and emerging commercial robotaxi deployments, focusing on architectural design, deployment strategies, safety considerations and industry implications. A key emerging product category is supervised E2E driving, often referred to as FSD (Supervised) or L2 plus plus, which several manufacturers plan to deploy from 2026 onwards. These systems can perform most of the Dynamic Driving Task (DDT) in complex environments while requiring human supervision, shifting the driver's role to safety oversight. Early operational evidence suggests E2E learning handles the long tail distribution of real world driving scenarios and is becoming a dominant commercial strategy. We also discuss how similar architectural advances may extend beyond autonomous vehicles (AV) to other
embodied AI systems, including
humanoid robotics.
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