This paper investigates the physical layer security of a satellite network, whose downlink spectral resource is shared with terrestrial cellular network. We propose to employ multi-antenna base station (BS) as source green interference enhance secure transmission in By taking mutual between these two networks into account, we first formulate constrained optimization problem maximize instantaneous rate user while satisfying probability constraint user. Then, assumption that imperfect channel...

In this paper, we address the issue of joint beamforming (BF) and power control for a device-to-device (D2D) communication underlaying cellular network, where wireless channels D2D link base station to user equipment experience Rician correlated Rayleigh fading, respectively. Based on property integral first formulate constrained optimization problem minimize total transmit devices in while meeting quality-of-service requirement both users suppressing mutual interference certain level. Then,...

This letter investigates the effect of cochannel interference (CCI) on a hybrid satellite-terrestrial cooperative relay network (HSTCN), where both satellite-destination and satellite-relay links undergo shadowed Rician fading, whereas relay-destination link follows Rayleigh fading. By assuming that decode-and-forward (DF) protocol is adopted at terrestrial relay, destination corrupted by multiple CCI, we first derive analytical expression for moment generating function (MGF) output...

This paper proposes a robust beamforming (BF) scheme to enhance the physical layer security (PLS) of multibeam satellite system operating at Ka band. By considering effects beam gain, path loss, and rain attenuation, we first formulate constrained optimization problem maximize minimal achievable secrecy rate multiuser under assumption imperfect eavesdropping channel constraint total transmit power on satellite. Since is non-convex mathematically intractable, exploit sequential convex...

This letter investigates the outage performance of a multi-antenna cognitive decode-and-forward (DF) hybrid satellite-terrestrial relay network (HSTRN) with beamforming (BF), where secondary source and can coexist primary user (PU) as long their interference imposed to PU is below predefined threshold. Specifically, novel closed-form expression for probability (OP) are derived. Furthermore, asymptotic OP at high SNR developed reveal diversity order code gain considered network. Finally,...

We investigate multiuser uplink communications from multiple single-antenna users to a base station (BS), which is equipped with fluid antennas (FAs) and adopts zero-forcing receivers decode signals. aim optimize antennas' positions at the BS, minimize total transmit power of all subject minimum rate requirement. After applying transformations, we show that problem equivalent minimizing sum each eigenvalue's reciprocal matrix, function BS. Subsequently, projected gradient descent (PGD)...

Satellite and unmanned aerial vehicle (UAV) integrated networks (SUINs) are considered as a promising method to offer various Internet of Remote Things (IoRT) applications. In this article, we investigate the downlink transmission SUINs where satellite-to-UAV link uses free-space optical (FSO) technology with an equal gain combining (EGC) scheme while links from UAV IoRT devices exploit radio frequency (RF) space-division multiple access (SDMA) technique. Specifically, considering that only...

We consider the movable-antenna (MA) array-enabled wireless communication with coordinate multi-point (CoMP) reception, where multiple destinations adopt maximal ratio combination technique to jointly decode common message sent from transmitter equipped MA array. Our goal is maximize effective received signal-to-noise ratio, by optimizing transmit beamforming and positions of Although formulated problem highly non-convex, we reveal that it fundamental principal eigenvalue a hermite channel...

Energy efficiency and security issues are the main concerns in wireless sensor networks (WSNs) because of limited energy resources broadcast nature communication. Therefore, how to improve WSNs while enhancing performance has attracted widespread attention. In order solve this problem, paper proposes a new deep reinforcement learning (DRL)-based strategy, i.e., DeepNR enhance WSN. Specifically, proposed strategy approximates Q-value by designing neural network (DNN) adaptively learn state...

In this paper, we investigate a tradeoff between the secrecy rate (SR) and energy efficiency (EE) in an underlay cognitive radio network that consists of base station (CBS), user (CU), primary (PU), multiple eavesdroppers (EDs). By using so-called EE (SEE), which is defined as ratio SR to total power consumption CBS, design criterion, formulate SEE maximization (SEEM) problem for CBS-CU transmission under constraints transmit CU, quality-of-service (QoS) requirement PU. Since formulated...

This study investigates the secrecy performance of a hybrid satellite‐terrestrial relay network (HSTRN) in presence multiple eavesdroppers, where satellite link undergoes Shadowed‐Rician fading, while terrestrial follows Rayleigh fading. The authors suppose direct between and intended user is unavailable due to heavy shadowing adopt multi‐antenna using either decode‐and‐forward (DF) or an amplify‐and‐forward (AF) protocol assist transmission. By employing perfect channel state information...

This letter investigates the secrecy performance of a satellite wiretap channel with multi-user opportunistic scheduling. By considering some practical effects, such as multi-beam pattern and path loss, assuming that undergoes Shadowed-Rician fading parameters being integer, we derive closed-form expressions probability non-zero capacity, outage average capacity for channels. Numerical results confirm correctness effectiveness analysis.

The application of Non-Orthogonal Multiple Access (NOMA) technology into satellite-aerial-ground integrated networks can meet the requirements ultra-high rate and massive connectivity for Sixth-Generation (6G) communication systems. We consider an uplink NOMA scenario such a network where multiple users communicate with satellite under help Unmanned Aerial Vehicle (UAV) as aerial relay equipped phased array. Supposing that buffer-aided decode-and-forward protocol is adopted at UAV relay, we...

Large language models (LLMs) now achieve near-human performance on standard math word problem benchmarks (e.g., GSM8K), yet their true reasoning ability remains disputed. A key concern is that often produce confident, unfounded, answers to unanswerable problems. We introduce TreeCut, a synthetic dataset systematically generates infinite problems and answerable counterparts, by representing each question as tree removing chosen necessary conditions. Experiments show TreeCut effectively induce...

ABSTRACT In this paper, we investigate an unmanned aerial vehicle (UAV) enabled secure multicast communication system, where a UAV serves multiple legitimate ground users in the presence of coordinated eavesdroppers. Taking into account inherent jittering characteristics UAVs caused by airflow, aim to maximise worst‐case secrecy energy efficiency (SEE) under constrained transmission power budget. The formulated optimization problem is inherently non‐convex and challenging solve due combined...

Transcranial electrical stimulation, as a means of neural modulation, is increasingly favored by researchers. The distribution and magnitude the electric field generated within brain may directly affect results modulation. Therefore, it important to clarify change trend cortical determinants induced in endodermis at different ages during adult life cycle. In this study, we used SimNIBS software perform MR image segmentation realistic head model reconstruction on 476 individuals (aged 18 88...

In this paper, we investigate the power allocation of primary base station (PBS) and cognitive (CBS) across different orthogonal frequency division multiplexing (OFDM) subcarriers for energy-efficient secure downlink communication in OFDM-based radio networks (CRNs) with existence an eavesdropper having multiple antennas. For sake defending against eavesdropping, artificial noise is used to confuse at cost extra consumption. purpose improving energy efficiency (EE) communications, propose a...