Pub Date : 2026-02-09DOI: 10.1109/LCOMM.2026.3663044
Abdulmomen Ghalkha;Zhuojun Tian;Chaouki Ben Issaid;Mehdi Bennis
Conventional multimodal alignment methods assume mutual redundancy across all modalities, an assumption that fails in real-world distributed scenarios. We propose Sheaf-Align, a sheaf-theoretic framework for decentralized multimodal alignment that replaces single-space alignment with multiple comparison spaces. This approach models pairwise modality relations through sheaf structures and leverages decentralized contrastive learning-based objectives for training. SheafAlign overcomes the limitations of prior methods by not requiring mutual redundancy among all modalities, preserving both shared and unique information. Experiments on multimodal sensing datasets show superior zero-shot generalization, cross-modal alignment, and robustness to missing modalities, with 34% lower communication cost than state-of-the-art baselines.
{"title":"SheafAlign: A Sheaf-Theoretic Framework for Decentralized Multimodal Alignment","authors":"Abdulmomen Ghalkha;Zhuojun Tian;Chaouki Ben Issaid;Mehdi Bennis","doi":"10.1109/LCOMM.2026.3663044","DOIUrl":"https://doi.org/10.1109/LCOMM.2026.3663044","url":null,"abstract":"Conventional multimodal alignment methods assume mutual redundancy across all modalities, an assumption that fails in real-world distributed scenarios. We propose Sheaf-Align, a sheaf-theoretic framework for decentralized multimodal alignment that replaces single-space alignment with multiple comparison spaces. This approach models pairwise modality relations through sheaf structures and leverages decentralized contrastive learning-based objectives for training. SheafAlign overcomes the limitations of prior methods by not requiring mutual redundancy among all modalities, preserving both shared and unique information. Experiments on multimodal sensing datasets show superior zero-shot generalization, cross-modal alignment, and robustness to missing modalities, with 34% lower communication cost than state-of-the-art baselines.","PeriodicalId":13197,"journal":{"name":"IEEE Communications Letters","volume":"30 ","pages":"1175-1179"},"PeriodicalIF":4.4,"publicationDate":"2026-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=11386918","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147299478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-02-09DOI: 10.1109/LCOMM.2026.3662807
Yi Zhai;Wanguo Jiao;Mengqiu Tian;Huiting Yang
To supply energy for IoT devices, the reconfigurable intelligent surface (RIS) assisted integrated sensing and communication system with energy harvesting nodes becomes a common scenario in 6G. Considering a practical system with imperfect channel state information and nonlinear charging characteristics, this letter studies the sensing energy efficiency (SEE) maximization problem under the charging, communication, and sensing requirements. Since the charging rate, data transmission rate, and sensing quality interact and are related to the beamforming and RIS phase shifts, the formulated SEE maximization problem is highly coupled. To address this coupled problem, incorporating some optimization methods, an alternating optimization-based algorithm is then developed to jointly optimize the beamforming matrix and RIS phase shifts. Simulation results demonstrate that the proposed algorithm achieves robust SEE improvement and a balance among communication, sensing, and charging.
{"title":"Maximize Sensing Energy Efficiency of RIS-Assisted ISCPT Systems With Imperfect Channels and Charging","authors":"Yi Zhai;Wanguo Jiao;Mengqiu Tian;Huiting Yang","doi":"10.1109/LCOMM.2026.3662807","DOIUrl":"https://doi.org/10.1109/LCOMM.2026.3662807","url":null,"abstract":"To supply energy for IoT devices, the reconfigurable intelligent surface (RIS) assisted integrated sensing and communication system with energy harvesting nodes becomes a common scenario in 6G. Considering a practical system with imperfect channel state information and nonlinear charging characteristics, this letter studies the sensing energy efficiency (SEE) maximization problem under the charging, communication, and sensing requirements. Since the charging rate, data transmission rate, and sensing quality interact and are related to the beamforming and RIS phase shifts, the formulated SEE maximization problem is highly coupled. To address this coupled problem, incorporating some optimization methods, an alternating optimization-based algorithm is then developed to jointly optimize the beamforming matrix and RIS phase shifts. Simulation results demonstrate that the proposed algorithm achieves robust SEE improvement and a balance among communication, sensing, and charging.","PeriodicalId":13197,"journal":{"name":"IEEE Communications Letters","volume":"30 ","pages":"1121-1125"},"PeriodicalIF":4.4,"publicationDate":"2026-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147299539","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-02-06DOI: 10.1109/LCOMM.2026.3662205
Mengmeng Wang;Xin Su;Bei Liu;Xibin Xu
In this letter, we leverage rate-splitting multiple access (RSMA) to boost both the covert rate and sensing capabilities of integrated sensing and communication (ISAC) systems. Taking into account the impact of imperfect channel state information (CSI) on both Alice-to-Bobs and Alice-to-Willie links, we formulate a robust optimization problem involving the covert precoding and the rate splitting. The goal is to maximize the weighted sum of covert rate and sensing power (CRSP). To address the non-convex optimization problem, we put forward a constrained-convex-convex procedure (CCCP)-based precoding design algorithm which makes use of the semidefinite relaxation (SDR) technique and a penalty-based method to handle the rank-one constraint issue induced by SDR. Simulations indicate that the proposed scheme achieves performance improvements of 12.7% and 26.5% compared to traditional non-orthogonal multiple access (NOMA) and space division multiple access (SDMA), respectively.
{"title":"Robust Covert Precoding Design for RSMA-Enhanced Integrated Sensing and Communication Systems","authors":"Mengmeng Wang;Xin Su;Bei Liu;Xibin Xu","doi":"10.1109/LCOMM.2026.3662205","DOIUrl":"https://doi.org/10.1109/LCOMM.2026.3662205","url":null,"abstract":"In this letter, we leverage rate-splitting multiple access (RSMA) to boost both the covert rate and sensing capabilities of integrated sensing and communication (ISAC) systems. Taking into account the impact of imperfect channel state information (CSI) on both Alice-to-Bobs and Alice-to-Willie links, we formulate a robust optimization problem involving the covert precoding and the rate splitting. The goal is to maximize the weighted sum of covert rate and sensing power (CRSP). To address the non-convex optimization problem, we put forward a constrained-convex-convex procedure (CCCP)-based precoding design algorithm which makes use of the semidefinite relaxation (SDR) technique and a penalty-based method to handle the rank-one constraint issue induced by SDR. Simulations indicate that the proposed scheme achieves performance improvements of 12.7% and 26.5% compared to traditional non-orthogonal multiple access (NOMA) and space division multiple access (SDMA), respectively.","PeriodicalId":13197,"journal":{"name":"IEEE Communications Letters","volume":"30 ","pages":"1076-1080"},"PeriodicalIF":4.4,"publicationDate":"2026-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146223747","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-02-06DOI: 10.1109/LCOMM.2026.3662201
Plínio S. Dester;Richard Demo Souza;Paulo Cardieri
In this letter, we revisit the age-threshold slotted ALOHA (TSA) protocol, a decentralized random-access scheme in which each node transmits only when its local Age of Information (AoI) exceeds a predefined threshold, and propose a simple yet novel modification that significantly improves both AoI and throughput. The key refinement is to transmit with probability one precisely when the age threshold is reached, hence the name 1-persistent TSA. We prove that, under generate-at-will traffic, the proposed scheme can theoretically achieve a stationary performance equal to that of a coordinated TDMA protocol; however, this operating point entails a prohibitively large transient duration and is therefore not practical. By properly adjusting the age threshold, a trade-off between steady-state performance and transient duration is obtained, yielding a practical regime in which the proposed scheme outperforms both the original TSA and stationary age-based thinning (SAT). Simulation results further show that these performance gains persist in the presence of transmission errors.
{"title":"Analysis of the 1-Persistent Age Threshold Slotted ALOHA","authors":"Plínio S. Dester;Richard Demo Souza;Paulo Cardieri","doi":"10.1109/LCOMM.2026.3662201","DOIUrl":"https://doi.org/10.1109/LCOMM.2026.3662201","url":null,"abstract":"In this letter, we revisit the age-threshold slotted ALOHA (TSA) protocol, a decentralized random-access scheme in which each node transmits only when its local Age of Information (AoI) exceeds a predefined threshold, and propose a simple yet novel modification that significantly improves both AoI and throughput. The key refinement is to transmit with probability one precisely when the age threshold is reached, hence the name 1-persistent TSA. We prove that, under generate-at-will traffic, the proposed scheme can theoretically achieve a stationary performance equal to that of a coordinated TDMA protocol; however, this operating point entails a prohibitively large transient duration and is therefore not practical. By properly adjusting the age threshold, a trade-off between steady-state performance and transient duration is obtained, yielding a practical regime in which the proposed scheme outperforms both the original TSA and stationary age-based thinning (SAT). Simulation results further show that these performance gains persist in the presence of transmission errors.","PeriodicalId":13197,"journal":{"name":"IEEE Communications Letters","volume":"30 ","pages":"1066-1070"},"PeriodicalIF":4.4,"publicationDate":"2026-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146223619","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-02-03DOI: 10.1109/LCOMM.2026.3660829
Matteo Nerini;Bruno Clerckx
This letter investigates wireless systems aided by dual-polarized intelligent surfaces. We compare reconfigurable intelligent surface (RIS), which adjust their reflection matrices, with movable signals operating with fixed intelligent surface (FIS), which adjust the signal frequency while the surface properties remain fixed. For both RIS and FIS, we consider surfaces with a diagonal reflection matrix, named diagonal RIS/FIS, and surfaces with a reflection matrix not limited to being diagonal, named beyond-diagonal RIS/FIS. Movable signals with FIS always outperform RIS, achieving at least a fourfold gain. When transmitter and receiver polarizations differ, beyond-diagonal FIS further enhances performance.
{"title":"Movable Signals With Dual-Polarized Fixed Intelligent Surfaces: Beyond Diagonal Reflection Matrices","authors":"Matteo Nerini;Bruno Clerckx","doi":"10.1109/LCOMM.2026.3660829","DOIUrl":"https://doi.org/10.1109/LCOMM.2026.3660829","url":null,"abstract":"This letter investigates wireless systems aided by dual-polarized intelligent surfaces. We compare reconfigurable intelligent surface (RIS), which adjust their reflection matrices, with movable signals operating with fixed intelligent surface (FIS), which adjust the signal frequency while the surface properties remain fixed. For both RIS and FIS, we consider surfaces with a diagonal reflection matrix, named diagonal RIS/FIS, and surfaces with a reflection matrix not limited to being diagonal, named beyond-diagonal RIS/FIS. Movable signals with FIS always outperform RIS, achieving at least a fourfold gain. When transmitter and receiver polarizations differ, beyond-diagonal FIS further enhances performance.","PeriodicalId":13197,"journal":{"name":"IEEE Communications Letters","volume":"30 ","pages":"1096-1100"},"PeriodicalIF":4.4,"publicationDate":"2026-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146223624","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-02-03DOI: 10.1109/LCOMM.2026.3659912
Ivy Selorm Dogbey;Yongjae Lee;Jihwan Moon;Taehoon Kim;Inkyu Bang
Satellite communication (SatCom) networks recently require more robust authentication techniques than before, driven by the increasing demands of applications such as commercial communication services and military operations. A physical-layer authentication (PLA) technique that exploits inherent wireless communication features, such as channel fading characteristics, has emerged as a promising solution against potential threats to the networks. Recent studies have shown that machine learning-based PLA methods can effectively compensate for the unexpected threats to traditional security protocols. However, previous research has not sufficiently considered practical feasibility, which is crucial, especially in SatCom networks (e.g., operating time limit). This letter presents enhanced physical-layer authentication with super-resolution for satellites (ePASS), integrating convolutional neural network models and super-resolution techniques for rapid authentication in SatCom networks. We evaluate the practical feasibility and detection performance of the proposed ePASS against spoofing attacks through extensive simulations, compared with the existing schemes.
{"title":"Lightweight Physical-Layer Authentication via IQ Sample Super-Resolution in LEO Satellite Networks","authors":"Ivy Selorm Dogbey;Yongjae Lee;Jihwan Moon;Taehoon Kim;Inkyu Bang","doi":"10.1109/LCOMM.2026.3659912","DOIUrl":"https://doi.org/10.1109/LCOMM.2026.3659912","url":null,"abstract":"Satellite communication (SatCom) networks recently require more robust authentication techniques than before, driven by the increasing demands of applications such as commercial communication services and military operations. A physical-layer authentication (PLA) technique that exploits inherent wireless communication features, such as channel fading characteristics, has emerged as a promising solution against potential threats to the networks. Recent studies have shown that machine learning-based PLA methods can effectively compensate for the unexpected threats to traditional security protocols. However, previous research has not sufficiently considered practical feasibility, which is crucial, especially in SatCom networks (e.g., operating time limit). This letter presents enhanced physical-layer authentication with super-resolution for satellites (ePASS), integrating convolutional neural network models and super-resolution techniques for rapid authentication in SatCom networks. We evaluate the practical feasibility and detection performance of the proposed ePASS against spoofing attacks through extensive simulations, compared with the existing schemes.","PeriodicalId":13197,"journal":{"name":"IEEE Communications Letters","volume":"30 ","pages":"1180-1184"},"PeriodicalIF":4.4,"publicationDate":"2026-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147299593","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-02-03DOI: 10.1109/LCOMM.2026.3660993
Yaqin Zhao;Yuchen Liu;Longwen Wu
Instantaneous frequency estimation is significant in signal processing for non-stationary multi-component signals in dense time-frequency environments. Researchers studied different algorithms for instantaneous frequency to suppress frequency switching errors. However, many classical algorithms are susceptible to errors in the time-frequency distribution (TFD) and noise at instantaneous frequencies, which often degrades their performance for multi-component frequency estimation. We propose a hybrid genetic algorithm-optimized adaptive directional time-frequency distribution (HGA-ADTFD) to improve the efficiency of multi-signal processing in TFD. The proposed HGA-ADTFD algorithm optimizes TFD using genetic parameter optimization. Crucially, the algorithm implements a joint calibration strategy that fuses local linear segments from the Hough transform with continuous paths from the Viterbi algorithm to determine the final instantaneous frequency. The proposed HGA-ADTFD algorithm achieves a minimum root mean square error for the final instantaneous frequency value, which is reduced to 0.5 MHz (the sampling frequency is 100 MHz).
{"title":"IF Estimation in Multi-Component Signals Via Hough-Viterbi Algorithm With HGA-ADTFD","authors":"Yaqin Zhao;Yuchen Liu;Longwen Wu","doi":"10.1109/LCOMM.2026.3660993","DOIUrl":"https://doi.org/10.1109/LCOMM.2026.3660993","url":null,"abstract":"Instantaneous frequency estimation is significant in signal processing for non-stationary multi-component signals in dense time-frequency environments. Researchers studied different algorithms for instantaneous frequency to suppress frequency switching errors. However, many classical algorithms are susceptible to errors in the time-frequency distribution (TFD) and noise at instantaneous frequencies, which often degrades their performance for multi-component frequency estimation. We propose a hybrid genetic algorithm-optimized adaptive directional time-frequency distribution (HGA-ADTFD) to improve the efficiency of multi-signal processing in TFD. The proposed HGA-ADTFD algorithm optimizes TFD using genetic parameter optimization. Crucially, the algorithm implements a joint calibration strategy that fuses local linear segments from the Hough transform with continuous paths from the Viterbi algorithm to determine the final instantaneous frequency. The proposed HGA-ADTFD algorithm achieves a minimum root mean square error for the final instantaneous frequency value, which is reduced to 0.5 MHz (the sampling frequency is 100 MHz).","PeriodicalId":13197,"journal":{"name":"IEEE Communications Letters","volume":"30 ","pages":"1051-1055"},"PeriodicalIF":4.4,"publicationDate":"2026-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146223644","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-02-03DOI: 10.1109/LCOMM.2026.3660876
Roberto López-Valcarce
Broadband signal alignment (BSA) is a recently proposed scheme that introduces frequency-domain repetition coding in multicarrier transmission. Combined with canonical correlation analysis (CCA) at the multiantenna receiver, this approach provides robustness against strong interference. We derive an analytical expression for the power spectral density (PSD) of BSA-encoded multicarrier signals and show that the original scheme generally degrades out-of-band sidelobes. We then propose a modified BSA approach that unlocks additional degrees of freedom to be exploited for sidelobe reduction while preserving the interference resilience of the original scheme. Our analysis reveals that the frequency-domain data repetition pattern is a critical design parameter, as it significantly impacts both spectral characteristics and error-rate performance.
{"title":"Spectral Properties of Multicarrier Signals Under Broadband Signal Alignment","authors":"Roberto López-Valcarce","doi":"10.1109/LCOMM.2026.3660876","DOIUrl":"https://doi.org/10.1109/LCOMM.2026.3660876","url":null,"abstract":"Broadband signal alignment (BSA) is a recently proposed scheme that introduces frequency-domain repetition coding in multicarrier transmission. Combined with canonical correlation analysis (CCA) at the multiantenna receiver, this approach provides robustness against strong interference. We derive an analytical expression for the power spectral density (PSD) of BSA-encoded multicarrier signals and show that the original scheme generally degrades out-of-band sidelobes. We then propose a modified BSA approach that unlocks additional degrees of freedom to be exploited for sidelobe reduction while preserving the interference resilience of the original scheme. Our analysis reveals that the frequency-domain data repetition pattern is a critical design parameter, as it significantly impacts both spectral characteristics and error-rate performance.","PeriodicalId":13197,"journal":{"name":"IEEE Communications Letters","volume":"30 ","pages":"1061-1065"},"PeriodicalIF":4.4,"publicationDate":"2026-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146223580","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This letter proposes a novel three-tier content caching architecture for Vehicular Fog Caching (VFC)-assisted platoon, where the VFC is formed by the vehicles driving near the platoon. The system strategically coordinates storage across local platoon vehicles, dynamic VFC clusters, and cloud server (CS) to minimize content retrieval latency. To efficiently manage distributed storage, we integrate large language models (LLMs) for real-time and intelligent caching decisions. The proposed approach leverages LLMs’ ability to process heterogeneous information, including user profiles, historical data, content characteristics, and dynamic system states. Through a designed prompting framework encoding task objectives and caching constraints, the LLMs formulate caching as a decision-making task, and our hierarchical deterministic caching mapping strategy enables adaptive requests prediction and precise content placement across three tiers without frequent retraining. Simulation results demonstrate the advantages of our proposed caching scheme.
{"title":"LLM-Empowered Cooperative Content Caching in Vehicular Fog Caching-Assisted Platoon Networks","authors":"Bowen Tan;Qiong Wu;Pingyi Fan;Kezhi Wang;Nan Cheng;Wen Chen","doi":"10.1109/LCOMM.2026.3660373","DOIUrl":"https://doi.org/10.1109/LCOMM.2026.3660373","url":null,"abstract":"This letter proposes a novel three-tier content caching architecture for Vehicular Fog Caching (VFC)-assisted platoon, where the VFC is formed by the vehicles driving near the platoon. The system strategically coordinates storage across local platoon vehicles, dynamic VFC clusters, and cloud server (CS) to minimize content retrieval latency. To efficiently manage distributed storage, we integrate large language models (LLMs) for real-time and intelligent caching decisions. The proposed approach leverages LLMs’ ability to process heterogeneous information, including user profiles, historical data, content characteristics, and dynamic system states. Through a designed prompting framework encoding task objectives and caching constraints, the LLMs formulate caching as a decision-making task, and our hierarchical deterministic caching mapping strategy enables adaptive requests prediction and precise content placement across three tiers without frequent retraining. Simulation results demonstrate the advantages of our proposed caching scheme.","PeriodicalId":13197,"journal":{"name":"IEEE Communications Letters","volume":"30 ","pages":"1026-1030"},"PeriodicalIF":4.4,"publicationDate":"2026-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146223651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-02-03DOI: 10.1109/LCOMM.2026.3659877
Cheng-Yu Pai;Yi-Xuan Zhong;Chao-Yu Chen
Two-dimensional (2D) Golay complementary array sets (GCASs) have been widely used to design omnidirectional precoding matrices for massive multi-input multi-output (MIMO) systems with uniform rectangular arrays (URAs), owing to their favorable 2D autocorrelation properties. However, most existing 2D GCAS constructions are tailored for analog precoding architectures that employ a fully-connected structure (FCS), with limited attention given to the design of precoding schemes for a partially-connected structure (PCS). To address this gap, this letter proposes a new class of 2D sparse GCASs (SGCASs) that incorporate controllable zero elements, enabling efficient precoding design for PCS. The proposed construction is based on 2D restricted generalized Boolean functions (RGBFs) and enables flexible array and set sizes. Moreover, the proposed method is compatible with both PCS and FCS, offering enhanced design flexibility. Simulation results demonstrate that the proposed SGCASs achieve omnidirectional transmission and improved bit error rate (BER) performance.
{"title":"Two-Dimensional Sparse Golay Complementary Array Sets for Omnidirectional Transmission in Massive MIMO Systems","authors":"Cheng-Yu Pai;Yi-Xuan Zhong;Chao-Yu Chen","doi":"10.1109/LCOMM.2026.3659877","DOIUrl":"https://doi.org/10.1109/LCOMM.2026.3659877","url":null,"abstract":"Two-dimensional (2D) Golay complementary array sets (GCASs) have been widely used to design omnidirectional precoding matrices for massive multi-input multi-output (MIMO) systems with uniform rectangular arrays (URAs), owing to their favorable 2D autocorrelation properties. However, most existing 2D GCAS constructions are tailored for analog precoding architectures that employ a fully-connected structure (FCS), with limited attention given to the design of precoding schemes for a partially-connected structure (PCS). To address this gap, this letter proposes a new class of 2D sparse GCASs (SGCASs) that incorporate controllable zero elements, enabling efficient precoding design for PCS. The proposed construction is based on 2D restricted generalized Boolean functions (RGBFs) and enables flexible array and set sizes. Moreover, the proposed method is compatible with both PCS and FCS, offering enhanced design flexibility. Simulation results demonstrate that the proposed SGCASs achieve omnidirectional transmission and improved bit error rate (BER) performance.","PeriodicalId":13197,"journal":{"name":"IEEE Communications Letters","volume":"30 ","pages":"1081-1085"},"PeriodicalIF":4.4,"publicationDate":"2026-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146223720","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}