Physical Communication最新文献_第7页

Energy-efficient joint power control and channel allocation for D2D communication underlaying cellular network 为覆盖蜂窝网络的 D2D 通信提供高能效联合功率控制和信道分配

IF 2 4区计算机科学 Q3 ENGINEERING, ELECTRICAL & ELECTRONIC

Physical Communication

Pub Date : 2024-11-24 DOI: 10.1016/j.phycom.2024.102552

Langlue Wei, Zheng Guan

The Device-to-device (D2D) communication technology can significantly improve the efficiency of wireless spectrum resources and expand the communication system’s capacity. In order to enhance the energy efficiency (EE) of D2D communication, a two-stage cross-layer optimization approach in which joint power control and channel allocation is proposed. In this work, the optimization objective is to maximize the total EE of D2D users (DUEs) to enable green D2D communications in cellular networks. The proposed resource allocation problems are NP-hard, which is typically difficult to solve directly. We decouple the EE optimization problem of joint power control and channel allocation into two sub-problems: Power Control and Channel Allocation. First, the Improved Grey Wolf Optimization (IGWO) algorithm is proposed to obtain the optimal transmission power of DUEs and Cellular users (CUEs) in the first phase. Then, the Hungarian Algorithm (HA) is utilized to accomplish optimal channel match for DUEs and CUEs in the second phase. Compared to other alternative algorithms, the simulation results show that the suggested scheme effectively improves the system’s EE.

设备到设备（D2D）通信技术能显著提高无线频谱资源的效率，扩大通信系统的容量。为了提高 D2D 通信的能效（EE），提出了一种联合功率控制和信道分配的两阶段跨层优化方法。在这项工作中，优化目标是最大化 D2D 用户（DUEs）的总能效，以实现蜂窝网络中的绿色 D2D 通信。所提出的资源分配问题是 NP 难问题，通常很难直接解决。我们将联合功率控制和信道分配的 EE 优化问题解耦为两个子问题：功率控制和信道分配。首先，我们提出了改进灰狼优化（IGWO）算法，以在第一阶段获得 DUE 和蜂窝用户（CUE）的最佳传输功率。然后，在第二阶段利用匈牙利算法（HA）实现 DUE 和 CUE 的最佳信道匹配。与其他替代算法相比，仿真结果表明所建议的方案能有效改善系统的 EE。

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引用次数: 0

Cooperative terahertz quantum key distribution: Secret key rate analysis and optimization 协同太赫兹量子密钥分配：密钥速率分析与优化

IF 2 4区计算机科学 Q3 ENGINEERING, ELECTRICAL & ELECTRONIC

Physical Communication

Pub Date : 2024-11-23 DOI: 10.1016/j.phycom.2024.102551

Parth Toshniwal , Justin Jose , Sumit Gautam , Vimal Bhatia , Ondrej Krejcar

In the recent years, there has been a growing interest in quantum key distribution (QKD) as a promising alternative to conventional cryptographic methods. QKD offers potential for ensuring absolute security in communication networks, leveraging the principles of quantum mechanics. This study diverges from previous research by investigating a cooperative continuous variable QKD (CVQKD) system operating at terahertz (THz) frequencies with multiple input multiple output (MIMO) technology, wherein the source and destination are assisted by a trusted decode-and-forward (DF) relay. Our focus lies on evaluating the secret key rate (SKR) of this system under direct reconciliation conditions and subsequently optimizing power and relay location to maximize the SKR. We address the practical concern of potential eavesdropping between the relay and the destination. Specifically, our analysis centers on the SKR performance of the coherent state-based CVQKD protocol under direct reconciliation conditions. Through numerical simulations, we demonstrate the significant enhancement in SKR achievable through optimization in the cooperative QKD system, yielding several noteworthy insights.

近年来，人们对量子密钥分发（QKD）越来越感兴趣，认为它是传统密码方法的一种有前途的替代方案。利用量子力学原理，量子密钥分配为确保通信网络的绝对安全提供了潜力。本研究不同于以往的研究，研究了一种在太赫兹（THz）频率下使用多输入多输出（MIMO）技术的合作连续变量QKD （CVQKD）系统，其中源和目标由可信的解码转发（DF）中继辅助。我们的重点是评估该系统在直接对调条件下的密钥速率（SKR），然后优化功率和继电器位置以最大化SKR。我们解决了中继和目的地之间潜在窃听的实际问题。具体来说，我们的分析集中在直接对调条件下基于相干状态的CVQKD协议的SKR性能上。通过数值模拟，我们证明了通过优化合作QKD系统可以实现SKR的显着增强，并产生了一些值得注意的见解。

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引用次数: 0

Multi-objective optimization for active IRS-aided multi-group multicast systems with energy harvesting, integrated sensing and communication 具有能量收集、综合传感和通信功能的主动 IRS 辅助多组组播系统的多目标优化

IF 2 4区计算机科学 Q3 ENGINEERING, ELECTRICAL & ELECTRONIC

Physical Communication

Pub Date : 2024-11-23 DOI: 10.1016/j.phycom.2024.102549

Ha Hoang Kha, Pham Van Quyet

In this paper, we utilize an active intelligent reflecting surface (IRS) to assist wireless systems with multiple functionalities, including multi-group (MG) multicast (MC) transmission, integrated sensing and communication (ISAC) and wireless energy harvesting. Specifically, a multi-antenna base station (BS) simultaneously transmits communication signals to MG MC users and sensing signals towards targets, while other users can harvest energy from the received radio frequency signals. We formulate the joint design of the BS transmit precoders (TPs) and the IRS reflection coefficients (RCs) as multi-objective optimization problems (MOOPs) in which the objective functions of the sum rate maximization (SRM) and sum harvested energy maximization (SHEM) are considered under the constraints of transmit power at the BS, amplitude and power amplifications at the active IRS, minimum achievable rate of communication users (CUs), minimum harvested energy of energy harvesting users (EHUs), and beamforming pattern similarity for sensing. To tackle the nonconvexity characteristics of the formulated design problems, we leverage alternating optimization (AO) frameworks to decompose the original problems into subproblems. In the subproblems, we seek appropriate surrogate functions by following majorization–minimization (MaMi) techniques to convert the subproblems into convex ones. Then, iterative algorithms are developed to obtain the optimal BS TPs and IRS RCs. The numerical simulations are carried out to validate the effectiveness of the proposed methods. The numerical results also reveal useful insights in the tradeoffs between the performance metrics and demonstrate the superior performance of systems with an active IRS in comparison with those without an IRS or with a passive IRS.

在本文中，我们利用有源智能反射面（IRS）协助无线系统实现多种功能，包括多组（MG）组播（MC）传输、综合传感与通信（ISAC）和无线能量采集。具体来说，多天线基站（BS）可同时向多组多播（MG MC）用户发射通信信号，并向目标发射传感信号，而其他用户则可从接收到的射频信号中获取能量。我们将 BS 发射前置编码器（TPs）和 IRS 反射系数（RCs）的联合设计表述为多目标优化问题（MOOPs），其中在 BS 发射功率的约束下考虑了总速率最大化（SRM）和总收获能量最大化（SHEM）的目标函数、有源 IRS 的振幅和功率放大、通信用户（CUs）的最小可实现速率、能量收集用户（EHUs）的最小收获能量以及用于传感的波束成形模式相似性等约束条件下，考虑总速率最大化（SRM）和总收获能量最大化（SHEM）的目标函数。为了解决设计问题的非凸特性，我们利用交替优化（AO）框架将原始问题分解为子问题。在子问题中，我们通过大化-最小化（MaMi）技术寻求适当的代用函数，将子问题转化为凸问题。然后，我们开发了迭代算法，以获得最佳的 BS TP 和 IRS RC。通过数值模拟验证了所提方法的有效性。数值结果还揭示了性能指标之间权衡的有用见解，并证明了有源 IRS 的系统与无 IRS 或有源 IRS 的系统相比具有更优越的性能。

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引用次数: 0

Performance analysis of IRS-assist dual-hop wireless communication system irs辅助双跳无线通信系统的性能分析

IF 2 4区计算机科学 Q3 ENGINEERING, ELECTRICAL & ELECTRONIC

Physical Communication

Pub Date : 2024-11-23 DOI: 10.1016/j.phycom.2024.102550

Moumita Jana , Sanjay Kumar

The IRS-assist or smart radio environment technique is a widely developing technology that network providers can use to establish sustained connectivity between end-user terminals and central data units for the next-generation wireless standards. This article introduced a simple and more accurate link-switching technique for dual-hop communication: a single link-switching threshold (SLST) algorithm to provide an uninterrupted linkage between the transceiver terminals. Depending on the severity of the communicating channel under a dual-hop system, links can do auto switches between themselves and furnish continuous connectivity between end-user terminals. Due to a discrete number of phase shifts of the IRS elements, phase and quantization errors are induced in the channel; the proposed system can also optimize the phase and quantization errors. Besides, this work investigates improving the physical layer performance of the dual-hop wireless communication system under the combined effect of phase shift and quantization error with the introduction of the SLST method. For this particular, three performance metrics have been encountered: the outage probability (OP), average bit error rate (ABER), and average capacity (bits/s/Hz). A new, more accurate mathematical framework using the Meijer’G function has been constructed to evaluate worthwhile analytical derivation. Under analytical calculation, we have assumed the primary link experienced with common Rayleigh fading and the IRS-assist link (IAL) experienced with Nakagami-m distribution due to a large number of reflecting elements in the system. The proposed dual-hop system furnishes noteworthy benefits for each performance metric rather than individual links. Moreover, the suitable selection of quantization level and a number of reflecting elements confirm the exhibition of satisfactory outcomes and minimize the channel hardness of the system. Additionally, numerical simulation results from MATLAB, using Monte Carlo simulation, have been added to validate the analytical outcomes for every performance measure.

irs辅助或智能无线电环境技术是一项广泛发展的技术，网络提供商可以使用该技术在终端用户终端和下一代无线标准的中央数据单元之间建立持续连接。本文介绍了一种用于双跳通信的简单而更精确的链路交换技术：单链路交换阈值（SLST）算法，用于在收发器终端之间提供不间断的链接。在双跳系统下，根据通信信道的严重程度，链路可以在自己之间自动切换，并提供终端用户终端之间的连续连接。由于IRS元件相移的离散次数，在信道中会引起相位误差和量化误差；该系统还可以优化相位误差和量化误差。此外，本文还研究了引入SLST方法在相移和量化误差共同作用下提高双跳无线通信系统物理层性能的问题。对于这种情况，遇到了三个性能指标：中断概率（OP）、平均误码率（ABER）和平均容量（bits/s/Hz）。一个新的，更精确的数学框架使用梅杰函数已经构建评估有价值的解析推导。在解析计算中，由于系统中有大量反射元件，我们假设主链路经历共同瑞利衰落，irs -辅助链路（IAL）经历中agami-m分布。所提出的双跳系统为每个性能指标提供了显著的好处，而不是单个链路。此外，适当选择量化水平和一些反射元素，确保了系统显示满意的结果，并使系统的通道硬度最小化。此外，还添加了使用蒙特卡罗模拟的MATLAB数值模拟结果，以验证每个性能度量的分析结果。

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引用次数: 0

A machine learning-based physical layer authentication with phase impairments 基于机器学习的物理层验证与相位损伤

IF 2 4区计算机科学 Q3 ENGINEERING, ELECTRICAL & ELECTRONIC

Physical Communication

Pub Date : 2024-11-23 DOI: 10.1016/j.phycom.2024.102545

Zahra Ezzati Khatab , Abbas Mohammadi , Vahid Pourahmadi , Ali Kuhestani

In this paper, we propose a machine learning (ML) based physical layer authentication (PLA) using the physical features of I/Q imbalance, phase noise and carrier frequency offset (CFO) impairments. By examining the phase information in the presence of these impairments, the proposed PLA method is implemented. The system model includes one legal single-antenna transmitter using orthogonal frequency-division multiplexing (OFDM) modulation, one legal multiple-antennas receiver and one external attacker. The comprehensive studies are conducted for three cases phase noise and CFO utilization, I/Q imbalance utilization, and all three impairments utilization. Our simulations show that the PLA accuracy for the mentioned these cases is more than 98% for single antenna at the receiver. The accuracy can be even improved by using more received antennas. Our results highlight that the PLA accuracy is also affected by the number of OFDM subcarriers and the received signal-to-noise-ratio.

本文提出了一种基于机器学习（ML）的物理层验证（PLA）方法，利用了 I/Q 不平衡、相位噪声和载波频率偏移（CFO）损伤等物理特征。通过检查存在这些损伤时的相位信息，实现了所提出的 PLA 方法。系统模型包括一个使用正交频分复用（OFDM）调制的合法单天线发射器、一个合法多天线接收器和一个外部攻击者。我们对利用相位噪声和 CFO、利用 I/Q 不平衡和利用所有三种损伤的三种情况进行了综合研究。模拟结果表明，在上述情况下，接收器单天线的 PLA 精确度超过 98%。如果使用更多的接收天线，精度甚至还能提高。我们的结果突出表明，PLA 精度还受到 OFDM 子载波数量和接收信噪比的影响。

引用次数: 0

BRAG: Blind region-agnostic geolocation of LTE mobile users in urban areas BRAG：城市地区 LTE 移动用户的盲区地理定位

IF 2 4区计算机科学 Q3 ENGINEERING, ELECTRICAL & ELECTRONIC

Physical Communication

Pub Date : 2024-11-19 DOI: 10.1016/j.phycom.2024.102544

Mai Kafafy, Mohamed Khairy

Geolocation is the backbone of many novel location-intelligent applications. Additionally, geodata analysis helps model and predict spatiotemporal fluctuations in data traffic, which is important for network optimization, operation cost reduction, and power saving. Furthermore, geodata analysis can be utilized in fields such as transportation, urban planning, tourism, marketing, epidemiology, national statistics, and censuses. Cellular geolocation is advantageous when Global Positioning System (GPS) readings are not available, especially since it does not require altering the network infrastructure or installing expensive equipment. However, cellular geolocation is challenged by the high randomness and dynamics of the environment. In this paper, we propose a blind region-agnostic algorithm to geolocate Long-Term Evolution (LTE) mobile users in urban areas. The algorithm uses timing and signal strength readings, which are readily available at the serving evolved Node B (eNB), to calculate initial estimated positions. Following that, the algorithm uses correlations between the initial estimates along the user’s path to improve its geolocation accuracy. The proposed method does not require training or prior data collection, making it easy to implement in different regions. We tested the method on real data from drive tests in different cities, and the method achieved a mean error of 132 meters and a median error of 91 meters, compared to a mean error of 203 meters and a median error of 125 meters achieved by basic time-advance-based geolocation.

地理定位是许多新型定位智能应用的基础。此外，地理数据分析有助于模拟和预测数据流量的时空波动，这对于优化网络、降低运营成本和节省电力非常重要。此外，地理数据分析还可用于交通、城市规划、旅游、市场营销、流行病学、国家统计和人口普查等领域。在没有全球定位系统（GPS）读数的情况下，蜂窝地理定位具有优势，尤其是因为它不需要改变网络基础设施或安装昂贵的设备。然而，蜂窝地理定位面临着环境高度随机性和动态性的挑战。在本文中，我们提出了一种区域盲定位算法，用于对城市地区的长期演进（LTE）移动用户进行地理定位。该算法使用服务演进节点 B（eNB）随时提供的定时和信号强度读数来计算初始估计位置。然后，该算法利用用户路径上的初始估计值之间的相关性来提高地理定位的准确性。建议的方法不需要训练或事先收集数据，因此很容易在不同地区实施。我们在不同城市的驾驶测试真实数据上测试了该方法，结果显示，该方法的平均误差为 132 米，中位误差为 91 米，而基于时间提前量的基本地理定位方法的平均误差为 203 米，中位误差为 125 米。

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引用次数: 0

On the performance of dual-hop mixed THz-RF cooperative relay networks 关于双跳混合 THz-RF 协同中继网络的性能

IF 2 4区计算机科学 Q3 ENGINEERING, ELECTRICAL & ELECTRONIC

Physical Communication

Pub Date : 2024-11-19 DOI: 10.1016/j.phycom.2024.102543

Soumendu Das , Nagendra Kumar , Dharmendra Dixit

The 0.1–10 terahertz (THz) band theoretically offers the potential to provide high data rates for 6G and beyond infrastructure. Consequently, THz band communication can be utilized in wireless fiber extenders and backhaul networks. Nonetheless, THz band communication suffers significantly from losses due to molecular attenuation and pointing errors, which result from antenna misalignment caused by small antenna apertures. However, cooperative communication strategies exhibit considerable potential in enhancing the THz link. Additionally, to address THz link limitations, a blend of technologies is necessary. Therefore, in this paper, we consider a decode-and-forward (DF)-based mixed THz-radio frequency (RF) cooperative system model. Furthermore, an in-depth exploration of coherent quadrature amplitude modulation and non-coherent modulation schemes is undertaken. Exact expressions for end-to-end (e2e) outage probability (OP), moment generating function (MGF), and channel capacity (CC) are derived, along with exact average symbol error rate (ASER) expressions for both coherent and non-coherent modulation schemes. We also perform asymptotic analysis to determine the system’s diversity gain and coding gain. Moreover, we conduct a thorough performance analysis to examine the impact of various parameters on e2e performance. Finally, validation through Monte-Carlo simulations ensures system accuracy, facilitating the extraction of practical design principles for optimizing THz-RF cooperative systems.

从理论上讲，0.1-10 太赫兹（THz）频段有可能为 6G 及更高的基础设施提供高数据传输速率。因此，太赫兹频段通信可用于无线光纤扩展器和回程网络。然而，太赫兹波段通信因分子衰减和天线孔径过小导致的天线不对准造成的指向误差而受到严重损失。不过，合作通信策略在增强太赫兹链路方面具有相当大的潜力。此外，要解决太赫兹链路的局限性，必须融合各种技术。因此，在本文中，我们考虑了一种基于解码和前向（DF）的太赫兹射频（RF）混合合作系统模型。此外，我们还对相干正交幅度调制和非相干调制方案进行了深入探讨。我们推导出了端到端 (e2e) 中断概率 (OP)、矩产生函数 (MGF) 和信道容量 (CC) 的精确表达式，以及相干和非相干调制方案的精确平均符号错误率 (ASER) 表达式。我们还进行了渐近分析，以确定系统的分集增益和编码增益。此外，我们还进行了全面的性能分析，以研究各种参数对 e2e 性能的影响。最后，通过蒙特卡洛模拟进行验证，确保了系统的准确性，从而有助于提取实用的设计原则，优化 THz-RF 合作系统。

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引用次数: 0

UAV-assisted dual-hop RF communication: Performance analysis of outage probability and altitude optimization for multi-user systems 无人机辅助双跳射频通信：多用户系统的中断概率性能分析和高度优化

IF 2 4区计算机科学 Q3 ENGINEERING, ELECTRICAL & ELECTRONIC

Physical Communication

Pub Date : 2024-11-19 DOI: 10.1016/j.phycom.2024.102546

Deepika Latka, Mona Aggarwal, Swaran Ahuja

Unmanned Aerial Vehicles (UAV) are growingly used as communication relays in this modern era due to their unique capabilities and advantages which includes enhanced connectivity, cost effectiveness, flexibility, risk reduction and real time data surveillance. UAVs offer a versatile and efficient solution for enhancing communication networks, especially in situations where traditional infrastructure is inadequate or unavailable. In this manuscript, we present the dual hop UAV enabled wireless communication system where the data is broadcasted from Source (S) to Destination (D) through a UAV working as decode and forward (DF) relay (R). The data is transmitted from S to R via Radio frequency (RF) link and then the decoded data from R is forward to D with multiple users. Closed form analytical expressions of outage probability is analyzed which is further utilized to do the optimization analysis to find the optimum altitude of the UAV in order to exaggerate its system performance. Numerical results shows that there is need to find out the optimal altitude of the UAV so as to keep down the overall outage probability of the proposed system and to enhance the system quality. We also find the outage probability at higher Signal-to-Noise ratio (SNR) to study the system behavior deeply. It is clearly observable from the numerical analysis that the exact outage probability and asymptotic outage probability are exactly matching at higher SNR values concluding the validity of the proposed system. The derived expressions are authenticated by simulated results via Monte Carlo simulations.

无人驾驶飞行器（UAV）具有独特的功能和优势，包括增强连接性、成本效益、灵活性、降低风险和实时数据监控，因此在当今时代越来越多地被用作通信中继器。无人机为增强通信网络提供了一个多功能、高效的解决方案，尤其是在传统基础设施不足或不可用的情况下。在本手稿中，我们介绍了启用无人机的双跳无线通信系统，数据通过作为解码和转发（DF）中继（R）的无人机从源（S）广播到目的地（D）。数据通过射频（RF）链路从 S 传输到 R，然后 R 将解码后的数据转发给有多个用户的 D。分析了中断概率的封闭式分析表达式，并进一步利用这些表达式进行优化分析，以找到无人机的最佳高度，从而提高其系统性能。数值结果表明，有必要找出无人机的最佳飞行高度，以降低拟议系统的总体中断概率，提高系统质量。我们还发现了较高信噪比（SNR）下的中断概率，以深入研究系统行为。从数值分析中可以清楚地观察到，在较高信噪比值时，精确中断概率和渐近中断概率完全匹配，从而证明了所提系统的有效性。蒙特卡罗模拟的仿真结果验证了推导出的表达式。

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引用次数: 0

A switched full duplex MIMO architecture with digital linear and nonlinear cancellation 具有数字线性和非线性消除功能的交换式全双工多输入多输出架构

IF 2 4区计算机科学 Q3 ENGINEERING, ELECTRICAL & ELECTRONIC

Physical Communication

Pub Date : 2024-11-16 DOI: 10.1016/j.phycom.2024.102542

Mikail Erdem , Ozgur Gurbuz , Doruk Can Altintas , Hayrettin Ayar

Enabling full duplex (FD) in MIMO systems is challenging due to increased hardware complexity and increased training overhead required for canceling not only self-interference (SI) but also cross-link-interference (CLI) signals, considering both linear and nonlinear effects on each stream. In this paper, we propose switched FD MIMO (FD-SW-MIMO) architecture as a low-complexity, low-overhead solution, which enables stream-based nonlinear estimation to be performed independently from channel estimation, so that those nonlinear reference signals are fed to linear SI and CLI cancellation stages. For improved performance at high transmit power levels, the Random Fourier Features - Least Mean Squares (RFF-LMS) algorithm is employed on the residual SI and CLI signals per stream. Our experiments conducted on a software-defined radio based 2x2 FD MIMO test setup reveal that the proposed FD-SW-MIMO architecture can provide up to 12 dB enhancement over linear only digital cancellation. The proposed architecture requires only minor hardware modification(s), avoiding active analog cancellation circuitry and extra Tx/Rx chains. Requiring the same training overhead as linear only cancellation, FD-SW-MIMO architecture can quadruple the rate of HD SISO for low to moderate transmit power levels, and for high transmit power levels, the HD SISO rate is tripled due to slightly increased overhead.

在多输入多输出（MIMO）系统中实现全双工（FD）具有挑战性，这是因为硬件复杂性增加，而且考虑到每个数据流的线性和非线性效应，消除自干扰（SI）和跨链路干扰（CLI）信号所需的训练开销也增加了。在本文中，我们提出了交换式 FD MIMO（FD-SW-MIMO）架构，作为一种低复杂度、低开销的解决方案，它能使基于流的非线性估计与信道估计独立进行，从而将这些非线性参考信号馈送到线性 SI 和 CLI 消除阶段。为了提高高发射功率水平下的性能，在每个数据流的残余 SI 和 CLI 信号上采用了随机傅里叶特征-最小均方（RFF-LMS）算法。我们在基于软件定义无线电的 2x2 FD MIMO 测试装置上进行的实验表明，与线性数字消除相比，拟议的 FD-SW-MIMO 架构最多可增强 12 dB。拟议的架构只需对硬件进行少量修改，避免了有源模拟消除电路和额外的 Tx/Rx 链。FD-SW-MIMO 架构需要与仅线性消除相同的训练开销，在中低发射功率水平下，可将高清 SISO 速率提高四倍；在高发射功率水平下，由于开销略有增加，高清 SISO 速率可提高三倍。

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引用次数: 0

Dynamic energy efficient resource allocation in multi-user multi-IRS mmWave 6G networks 多用户多红外系统毫米波 6G 网络中的动态节能资源分配

IF 2 4区计算机科学 Q3 ENGINEERING, ELECTRICAL & ELECTRONIC

Physical Communication

Pub Date : 2024-11-16 DOI: 10.1016/j.phycom.2024.102547

Alireza Ghazavi Khorasgani , Foroogh S. Tabataba , Mohammad Sadegh Fazel , Mehdi Naderi Soorki

This study introduces a novel approach for energy-efficient resource allocation in millimeter-wave networks, assisted by multiple intelligent reflecting surfaces (IRS). The proposed framework optimizes the dynamic ON/OFF control and phase shifts of IRS elements, along with beamforming (BF) at access points (AP), under practical constraints. Unlike existing methods, our model enhances energy efficiency (EE) by optimizing a fixed number of ON IRS elements. We present innovative algorithms, including a modified nested fractional programming (NFP) for BF and a simulated annealing (SA)-type algorithm for phase shift and element selection. Our results demonstrate a 6.5-fold improvement in EE under a realistic scenario compared to benchmark, highlighting the effectiveness of our approach as a crucial strategy for future 6G networks.

本研究在多个智能反射面（IRS）的辅助下，为毫米波网络的高能效资源分配引入了一种新方法。所提出的框架在实际限制条件下优化了 IRS 元件的动态开/关控制和相移，以及接入点（AP）的波束成形（BF）。与现有方法不同的是，我们的模型通过优化固定数量的开/关 IRS 单元来提高能效（EE）。我们提出了创新算法，包括用于 BF 的改进嵌套分数编程（NFP）和用于相移和元素选择的模拟退火（SA）型算法。我们的研究结果表明，在现实场景下，与基准相比，EE 提高了 6.5 倍，这凸显了我们的方法作为未来 6G 网络重要战略的有效性。

引用次数: 0