Jian Chen

Xidian University · School of Telecommunications Engineering

We investigate covert communication in an intelligent reflecting surface (IRS)-assisted symbiotic radio (SR) system under the parasitic SR (PSR) and the commensal SR (CSR) cases, where an IRS is exploited to create a double reflection link for legitimate users and degrade the detection performance of the warden (W). Specifically, we derive an analy...

This paper investigates a mobile edge computing (MEC) network assisted by an unmanned aerial vehicle (UAV), where the moving UAV and a fixed ground base station cooperatively provide MEC services for multiple ground users. To evaluate the quality of service under this architecture, we first derive the successful edge computing probability (SECP) to...

A novel dynamic hybrid beamforming architecture is proposed to achieve the spatial multiplexing-power consumption tradeoff for near-field multiple-input multiple-output (MIMO) networks, where a switch module is integrated between the baseband digital and analog phase-shift module to control the number of activated RF chains. Based on this architect...

In this letter, we propose a symbiotic non-orthogonal multiple access (NOMA) mutually reinforcing paradigm for green massive access to better meet the diverse and challenging requirements of Internet-of-Things. In particular, the backscatter device (BD) utilizes the same spectrum resources of the legacy users for reflection while providing benefici...

This paper develops an edge-device collaborative Generative Semantic Communications (Gen SemCom) framework leveraging pre-trained Multi-modal/Vision Language Models (M/VLMs) for ultra-low-rate semantic communication via textual prompts. The proposed framework optimizes the use of M/VLMs on the wireless edge/device to generate high-fidelity textual...

Unmanned aerial vehicles (UAVs) have been envisioned as essential technology to enhance the service quality of wireless systems, whereas the security issue is unavoidable. In this paper, a reconfigurable intelligent surfaces (RIS)-aided air-to-ground secure communication paradigm is conceived, where the RIS is used to boost the security of confiden...

A novel near-field transmission framework is proposed for dynamic metasurface antenna (DMA)-enabled non-orthogonal multiple access (NOMA) networks. The base station (BS) exploits the hybrid beamforming to communicate with multiple near users (NUs) and far users (FUs) using the NOMA principle. Based on this framework, two novel beamforming schemes a...

To address the power and computation limitations of the Internet-of-Things (IoT) devices, this letter investigates integrating wireless power transfer (WPT) and mobile edge computing (MEC) with intelligent reflective surfaces (IRS) in 6G networks. An optimization problem is formulated to minimize the energy consumption of the access point (AP) for...

A near-field simultaneous wireless information and power transfer (SWIPT) network is investigated, where the hybrid beamforming architecture is employed at the base station (BS) for information transmission while charging energy harvesting users. A transmit power minimization problem is formulated by jointly optimizing the analog beamformer, the ba...

A near-field secure transmission framework is proposed. Employing the hybrid beamforming architecture, a multi-antenna base station (BS) transmits confidential information to a multi-antenna legitimate user (U) against a multi-antenna internal eavesdropper (E) in the near field. Based on the spherical-wave channel state information of U and E, a tw...

Unmanned aerial vehicle (UAV) assisted communications have been regarded as an effective solution to provide instant services. This paper proposes a novel reconfigurable intelligent surface (RIS) assisted multi-UAV system, where ground users are formed as multicast groups and served by multiple UAVs with coordinated multi-point technique. The goal...

This paper designs a helper-assisted offloading strategy in non-orthogonal multiple access enabled mobile edge computing systems, in order to guarantee the quality of service of the energy/delay-sensitive user equipments (UEs). To achieve a tradeoff between the energy consumption and the delay, we introduce a performance metric called energy-delay...

The time-sensitive networking (TSN) technique has shown its potential to provide deterministic communication guarantees for industrial applications. Specifically, the recently applied cyclic queuing and forwarding (CQF) mechanism in TSN can further provide bounded latency and stable delay jitter for time-triggered (TT) flows with simplified configu...

As wireless networks continue to advance, virtual reality (VR) transmission over wireless connections is progressively transitioning from concept to practical application. Although this technology can significantly enhance the VR user experience, its development bottleneck lies in the computing capacity of devices and transmission latency. Consider...

Current synthetic aperture radar (SAR) automatic target recognition (ATR) methods primarily focus on closed set recognition, i.e., they typically assume that the training set covers all target classes that appear in the test set. However, this assumption may not hold in practical scenarios, where it's inevitable to encounter high-value targets whos...

A reconfigurable intelligent surface (RIS) assisted semi-grant-free (SGF) non-orthogonal multiple access (NOMA) system is investigated. Unlike existing works that only focus on short-term resource allocation, we study a long-term power-saving optimization problem under queue stability constraints and utilize Lyapunov stability theory to deal with d...

This paper investigates covert communications in an integrated sensing and communications system, where a dual-functional base station (called Alice) covertly transmits signals to a covert user (called Bob) while sensing multiple targets, with one of them acting as a potential watcher (called Willie) and maliciously eavesdropping on legitimate comm...

This paper presents a novel simultaneously transmitting and reflecting reconfigurable intelligent surfaces (STAR-RIS) assisted mobile edge computing (MEC) system. We employ the semi-grant-free (SGF) non-orthogonal multiple access (NOMA) to improve the system's spectrum and energy efficiency, and the STAR-RIS to enhance the uplink communication from...

Integrated sensing and communication (ISAC) has been regarded as an emerging technique to satisfy the sensing requirements for future 6G networks. However, the confidential communication information embedded in the probing waveform could be eavesdropped by the radar targets, which leads to insecurity issues for ISAC systems. To this end, we propose...

This paper investigates a reconfigurable intelligent surface (RIS)-assisted wireless powered mobile edge computing (MEC) system, where an access point (AP) integrated with an MEC server first transmits energy signals to charge multiple energy-constrained devices in the downlink (DL), and then the devices utilize the harvested energy to perform MEC...

Heterogeneous cellular networks (HetNets) are widely recognized as representing the future development trend of networks and provide architectural support for the emergence of many new applications. For applications that are sensitive to reliability, carrier aggregation (CA) plays a crucial role in optimizing system performance by intelligently com...

Distributed computing enables Internet of vehicle (IoV) services by collaboratively utilizing the computing resources from the network edge and the vehicles. However, the computing interruption issue caused by frequent edge network handoffs, and a severe shortage of computing resources are two problems in providing IoV services. High altitude platf...

To promote the application of edge computing in wireless blockchain networks, this paper presents a business ecosystem, where edge computing is introduced to assist blockchain users in implementing the mining process. This paper exploits resource trading and miner competition to enable secure and efficient transactions in the presented business eco...

This letter proposes a new coupled phase-shift intelligent omni-surface (IOS) aided rate splitting multiple access (RSMA) transmission framework. Specifically, the base station (BS) splits user messages into common and private parts and precodes the common stream carefully to exploit the operation of IOS aided communication for spectral efficiency...

In this paper, we propose a new simultaneous information relaying and jamming (SIRJ) scheme based on a dual-functional reconfigurable intelligent surface (RIS) to achieve secure non-orthogonal multiple access communications. Specifically, the RIS elements are split into two groups, where elements in one group perform signal reflection to enhance th...

The explosion of wireless network services has led to a need for new technologies and resource allocation schemes. Device-to-device (D2D) can reduce the access pressure of base station (BS) equipment, and non-orthogonal multiple access (NOMA) can multiplex network spectrum resources. The integration of them can further improve the performance of mu...

With the large‐scale deployment of communication and computation units, the conventional radio access network has been gradually transformed into a sophisticated Cyber‐Physical System. Since the access network is put forward higher expectations for ultra‐reliable and low‐latency services, Short‐Packet Communications (SPC) based on Finite Blocklengt...

Coordinated multi-point (CoMP) transmission allows multiple base stations (BSs) to transmit the same signal to users simultaneously at the same resource block for higher throughput. It can be applied to the evolved Multimedia Broadcast/Multicast Service (eMBMS) framework to provide additional gains for users in the same multicast group. However, op...

Due to the huge number of devices with the differentiated requirement for latency and reliability, the uplink transmission of the Internet of Things (IoT) has the problem of excessive control signaling. In this regard, this paper proposes a distributed control strategy for Semi-Grant-Free (SGF) Non-Orthogonal Multiple Access (NOMA). By exploiting t...

Localization based on fingerprint has been viewed as a popular indoor localization technique, which uses the signal strength of different positions as the location fingerprint. The localization model can thus be constructed by analyzing the relationship between the location fingerprint and the target location. However, this method requires the manu...

Device-to-device (D2D) communication has been regarded as a promising solution to alleviate the mobile traffic explosion problem for its capabilities of improving system data rate and resource utilization. A reconfigurable intelligent surface (RIS) aided mobile D2D communications framework is investigated, where the RIS is deployed to improve commu...

To enhance the outage performance of downlink non-orthogonal multiple access (NOMA) systems, we investigate opportunistic user pair scheduling (UPS) as well as the joint power allocation and decoding order selection (PA-DOS) for the scheduled user pair. Unlike most existing literature where the UPS and PA-DOS schemes are solely driven by channel co...

The secure transmission of the simultaneously transmitting and reflecting reconfigurable intelligent surface (STAR-RIS) aided communication system is investigated. Considering the coupled phase shifts of STAR-RISs and the fair secrecy requirement of users, a new secure beamforming design is proposed for addressing the unique full-space mutual e...

This paper investigates computing task offloading from an Internet-of-Thing (IoT) device with limited transmit power to a mobile-edge computing (MEC) server located beyond the communication range of the IoT device. We propose an opportunistic cooperative offloading (OCO) strategy that recruits the IoT device’s nearby spatially random idle-state use...

We investigate joint power allocation and decoding order selection (PA-DOS) aimed at enhancing the outage performance of non-orthogonal multiple access (NOMA) systems. By considering the diverse target rates of users, new important properties of NOMA are revealed: When users' target rates satisfy certain conditions, the channel state information (C...

Distributed computing enables Internet of vehicle (IoV) services by collaboratively utilizing the computing resources from the network edge and the vehicles. However, the computing interruption issue caused by frequent edge network handoffs, and a severe shortage of computing resources are two problems in providing IoV services. High altitude platf...

A near-field simultaneous wireless information and power transfer (SWIPT) network is investigated, where the hybrid beamforming architecture is employed at the base station (BS) for information transmission while charging energy harvesting users. A transmit power minimization problem is formulated by jointly optimizing of the analog beamformer, the...

A near-field secure transmission framework is proposed. Employing the hybrid beamforming architecture, a base station (BS) transmits the confidential information to a legitimate user (U) against an eavesdropper (E) in the near field. A two-stage algorithm is proposed to maximize the near-field secrecy capacity. Based on the fully-digital beamformer...

This paper designs a helper-assisted resource allocation strategy in non-orthogonal multiple access (NOMA)-enabled mobile edge computing (MEC) systems, in order to guarantee the quality of service (QoS) of the energy/delay-sensitive user equipments (UEs). To achieve a tradeoff between the energy consumption and the delay, we introduce a novel perfo...

A simultaneously transmitting and reflecting surface (STARS) enabled integrated sensing and communications (ISAC) framework is proposed, where a novel bi-directional sensing-STARS architecture is devised to facilitate the full-space communication and sensing. Based on the proposed framework, a joint optimization problem is formulated, where the Cra...

A simultaneously transmitting and reflecting surface (STARS) enabled two-phase integrated sensing and communications (ISAC) framework is proposed, where a novel bi-directional sensing-STARS architecture is devised to facilitate the full-space communication and sensing in a time-switching manner. Based on the proposed framework, a joint optimizati...

Efficient scheduling of vehicle resources is of great significance to guarantee vehicle safety and to achieve a higher level of automated driving. Considering the performance fluctuations in data transmission and processing during driving, this paper proposes an adaptive data transmission and computation optimization scheme, where the concept of th...

This paper investigates a new self-sustainable intelligent omni-surface (S-IOS) aided multi-user wireless network, where the S-IOS harvests the radio frequency energy from the signals transmitted by the access point (AP) and exploits the harvested energy to provide full-dimensional beamforming services for the users. Three efficient operating proto...

Wireless virtual reality networks(WVRNs) provide seamless connectivity between virtual reality devices with colossal application and commercial value. However, the main problem restricting its development is the high energy and computational consumption in 3D video rendering on VR devices. To address this issue, we propose a novel coordinated multi...

We investigate joint power allocation and decoding order selection (PA-DOS) aimed at enhancing the outage performance of non-orthogonal multiple access (NOMA) systems. By considering the diverse target rates of users, new important properties of NOMA are revealed: When users' target rates satisfy certain conditions, the channel state information (C...

This paper investigates the secure transmission in a simultaneously transmitting and reflecting reconfigurable intelligent surface (STAR-RIS) assisted uplink non-orthogonal multiple access system, where the legitimate users send confidential signals to the base station by exploiting STAR-RIS to reconfigure the electromagnetic propagation environmen...

In order to achieve thousand-fold throughput improvements for future applications, heterogeneous cellular networks (HCNs) with ultra-densely deployed small cells have gained a great deal of attention in recent years. However, energy consumption is an increasing concern as base station deployment (BSs) becomes denser. In order to address this issue,...

In the vision of the future smart grid, the communication is often featured by wide range, massive connect, and low latency, which poses new requirements on the reachable distance and spectral efficiency of wireless communication. In this regard, this paper studies ergodic capacity enhancement by applying successive relay (SR) technology to a non-o...

Edge intelligence, a new paradigm to accelerate artificial intelligence (AI) applications by leveraging computing resources on the network edge, can be used to improve intelligent transportation systems (ITS). However, due to physical limitations and energy-supply constraints, the computing powers of edge equipment are usually limited. High altitud...

This letter investigates a new active intelligent omni-surface (IOS) aided non-orthogonal multiple access (NOMA) network. In particular, simple active devices are introduced into the IOS to overcome the “double-fading” effect. A sum achievable rate optimization problem is formulated, where the beamforming vector at the base station and the active I...

The secure transmission of the simultaneously transmitting and reflecting reconfigurable intelligent surface (STAR-RIS) aided communication system is investigated. Considering the coupled phase shifts of STAR-RISs and the fair secrecy requirement of users, a novel secure beamforming design is proposed for addressing the unique full-space mutual eav...

This paper investigates the physical layer security issue of the coordinated direct and untrusted relay transmissions, considering both uplink and downlink scenarios. To effectively prevent the untrusted relay from eavesdropping on the confidential information it receives, two novel interference-assisted jamming schemes are proposed, where the inte...

With the rapid development of Internet‐of‐Things (IoT) and mobile devices, the IoT applications become more computation‐intensive and latency‐sensitive, which bring severe challenges to the resource‐limited devices. Mobile Edge Computing has served as a key promising method to enhance the network's computing capability by enabling resource‐constrai...

A novel intelligent reconfigurable surface (IRS) assisted coordinated multi-point (CoMP) system is proposed. Our objective is to maximize the energy efficiency (EE) of this system by jointly optimizing base station (BS) clustering, user association, sub-carrier assignment, power allocation, and optimal design of the IRS, while satisfying the users’...

This letter investigates the cooperative computing in a non-orthogonal multiple access (NOMA)-enabled mobile edge computing (MEC) system consisting of one edge server, one user equipment (UE) and $M$ full-duplex helpers. For this system, we design an adaptive cooperative computing strategy that operates in one of two modes: the cooperative NOMA-M...

FemtoCaching technology, aiming at maximizing the access probability of streaming media transmission in heterogeneous cellular networks, is investigated in this paper. Firstly, five kinds of streaming media deployment schemes are proposed based on the network topology and the relationship between users and streaming media. Secondly, a matching algo...