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In this paper, we propose a deep reinforcement learning (DRL)-based framework to jointly minimize the ergodic age of information (AoI) and the total transmit power in an uplink (UL) cell-free massive multiple-input multiple-output (CF-mMIMO) system. In particular, the multiple-objective resource allocation problem is formulated into an optimization problem subject to quality-of-service (QoS) and m...Show More
In this letter, the problem of localizing in a wireless environment with non-line-of-sight (NLoS) propagation without strict time synchronization is being considered. This problem utilizes maximum likelihood (ML) estimation based on time-of-arrival (TOA) measurements. However, the original form of this problem is not convex and cannot be directly solved using standard convex optimization technique...Show More
The emerging fluid antenna system (FAS) technology enables multiple access utilizing deep fades in the spatial domain. This paradigm is known as fluid antenna multiple access (FAMA). Despite conceptual simplicity, the challenge of finding the position (a.k.a. port) that maximizes the signal-to-interference plus noise ratio (SINR) at the FAS receiver output, cannot be overstated. This letter propos...Show More
In this paper, we propose a robust resource allocation framework for an intelligent reflecting surface (IRS)-assisted multiple-input single-output (MISO) non-orthogonal multiple access (NOMA) system. In particular, a long-term robust sum-rate maximization problem is considered. The impacts of imperfect channel estimation on both the transmitter and the receiver are taken into account with an outag...Show More
In recent years, the multiple-input multiple-output (MIMO) non-orthogonal multiple-access (NOMA) systems have attracted a significant interest in the relevant research communities. As a potential precoding scheme, the generalized singular value decomposition (GSVD) can be adopted in MIMO-NOMA systems and has been proved to have a good trade-off for complexity and performance. In this paper, the pe...Show More
In this paper, we propose a robust design for an intelligent reflecting surface (IRS)-assisted multiple-input single output non-orthogonal multiple access (NOMA) system. By considering channel uncertainties, the original robust design problem is formulated as a sum-rate maximization problem under a set of constraints. In particular, the uncertainties associated with reflected channels through IRS ...Show More
Satellite communications have played a crucial role in communication networks for a long time and has been recently recognized as an important component of next-generation communication networks. As one of the performance indicators to evaluate reliability, the outage probability of a single-input multi-output (SIMO) satellite-terrestrial communication system modeled by shadowed Rician distributio...Show More
This letter investigates a joint intelligent transmissive surface (ITS) and intelligent reflecting surface (IRS)-assisted cell-free network. Specifically, various ITS-assisted base stations (BSs), handled via a central processing unit (CPU), broadcast information signals to multiple IoT devices, carried by active transmit beamforming and transmissive reflecting phase shifts. Meanwhile, an IRS pass...Show More
In this letter, we propose an unmanned aerial vehicle (UAV)-carried active reconfigurable intelligent surface (RIS)-assisted cooperative network (UARCN) with a source (S), a trustworthy user (U), and an untrustworthy user (E), which is bridged by multiple half-duplex decode-and-forward relays and an active RIS mounted on a hovering UAV. In the UARCN, both U, E, and relays receive the signal from S...Show More
This letter investigates a novel aerial intelligent reflecting surface (IRS)-assisted secure mobile communication system. In particular, the IRS is mounted on a unmanned aerial vehicle (UAV) to help a source transmit its confidential messages to a legitimate mobile user in the presence of a mobile eavesdropper. The aerial IRS can adjust its trajectory and phase-shift to track the moving user and p...Show More
The flexibility and controllable mobility of unmanned aerial vehicles (UAVs) render them easier to become aerial platforms carrying out integrated sensing and communication (ISAC) functionality, and the cooperation among multiple UAVs is a promising way to achieve simultaneous multi-static radar sensing and coordinated multiple point (CoMP) transmission, leading to an enhanced ISAC service. Howeve...Show More
In this letter, we propose a robust design for an intelligent reflecting surface (IRS)-aided multiple-input single-output (MISO) non-orthogonal multiple access (NOMA) system. In particular, the ergodic sum-rate maximization problem is formulated by taking into account the channel uncertainties of both direct links and the reflected links through IRS elements. The unbounded channel uncertainties wi...Show More
This letter considers the downlink transmission of an intelligent reflecting surface (IRS)-aided multi-carrier (MC) non-orthogonal multiple access (NOMA) system, referred to as the IRS-aided MC-NOMA system. Due to the limitations on the availability of the IRS, a limited number of channels can be served with the support of the available IRS units. Therefore, a competitive approach is proposed to a...Show More
Recently, the multiple-input–multiple-output (MIMO) nonorthogonal multiple-access (NOMA) transmission, denoted as MIMO- NOMA, has been widely applied for Internet of Things (IoT) systems due to its spectral efficiency. As a promising precoding method, the generalized singular value decomposition (GSVD)-based precoding scheme has been studied in MIMO- NOMA. In this study, we apply the GSVD-based pr...Show More
Falls have always been one of the major threats to the health and well-being of elderly people, particularly for those living alone. Both wearable and non-wearable fall detection systems have already been developed. However, the fall detection systems using WiFi channel state information (CSI) have attracted a significant interest from researchers due to their non-intrusive and low-cost nature. Th...Show More
Intelligent reflecting surface (IRS) has been recently integrated with emerging communication technologies to meet the demanding requirements of communication systems. This paper investigates the deployment of multi-IRS units in a hybrid time-domain multiple access (TDMA) and non-orthogonal multiple access (NOMA) system, referred to as a multi-IRS-aided hybrid TDMA-NOMA system. In particular, a se...Show More
Backscatter communication (BackCom) assisted non-orthogonal multiple access (NOMA) has received significant attention recently and can be applied to Internet of Things (IoT). The BackCom system aims to realize energy cooperation among the devices. NOMA is a well-known technique to enable spectrum cooperation among the devices, which motivates the combination of the two techniques. This letter focu...Show More
This paper investigates a novel maritime wireless surveillance scenario, where a legitimate monitor vessel moves around to eavesdrop the suspicious communication from a suspicious unmanned aerial vehicle (UAV) to a suspicious vessel with the help of a cooperative UAV. Specifically, the cooperative UAV can adjust its jamming power and trajectory to exactly control the transmission rate of the suspi...Show More
In this article, a joint power control and pairing-based resource allocation problem in the vehicle-to-everything (V2X) network are studied. This V2X network consists of a vehicle-to-infrastructure (V2I) link and a vehicle-to-vehicle (V2V) link. Therefore, the resource allocation problem has been formulated with the objective function of maximizing the V2I link's rate with the constraints of quali...Show More
The integration of simultaneous wireless information and power transfer (SWIPT) in multi-carrier non-orthogonal multiple access (NOMA) systems has been recently investigated as a potential paradigm to improve the lifespan of energy-constrained Internet-of-Things networks. In this letter, we develop a fairness-aware design for a multi-carrier NOMA SWIPT-based system that attempts to maximize the mi...Show More
This paper investigates an unmanned aerial vehicle (UAV)-enabled maritime secure communication network, where the UAV aims to provide the communication service to a legitimate mobile vessel in the presence of multiple eavesdroppers. In this maritime communication networks (MCNs), it is challenging for the UAV to determine its trajectory on the ocean, since it cannot land or replenish energy on the...Show More
Machine learning (ML) which is a subset of artificial intelligence is expected to unlock the potential of challenging large-scale problems in conventional massive multiple-input-multiple-output (CM-MIMO) systems. This introduces the concept of intelligent massive MIMO (I-mMIMO) systems. Due to the surge of application of different ML techniques in the enhancement of mMIMO systems for existing and ...Show More
In this paper, we consider an energy efficient resource allocation technique for a hybrid time division multiple access (TDMA) - non-orthogonal multiple access (NOMA) system. In such a hybrid system, the available time for transmission is divided into several sub-time slots, and a sub-time slot is allocated to serve a group of users (i.e., cluster). Furthermore, signals for the users in each clust...Show More
In this letter, the channel impairments compensation of visible light communication is formulated as a time sequence with memory prediction. Then we propose efficient nonlinear post equalization, using a combined long-short term memory (LSTM) and deep neural network (DNN), to learn the complicated channel characteristics and recover the original transmitted signal. We leverage the long-term memory...Show More
Unmanned aerial vehicle (UAV)-enabled communication has emerged as an irreplaceable technology in military, disaster relief and emergency scenarios. This correspondence investigates the average throughput in a UAV-enabled cognitive radio network, where the UAV is regarded as a dedicated secondary user to enhance the network coverage and spectral efficiency. Based on the probabilistic line-of-sight...Show More