Generating talking face videos from audio attracts lots of research interest. A few person-specific methods can generate vivid but require the target speaker's for training or fine-tuning. Existing person-generic have difficulty in generating realistic and lip-synced while preserving identity information. To tackle this problem, we propose a two-stage framework consisting audio-to-landmark generation landmark-to-video rendering procedures. First, devise novel Transformer-based landmark...

The radio environment map (REM), which can visualize the information of invisible electromagnetic spectrum, is vital for monitoring, management, and security spectrum resources in cognitive (CR) networks. In view a limited number sensors constrained sampling time, this paper presents new three-dimensional (3D) REM construction scheme based on sparse Bayesian learning (SBL). Firstly, we construct scenario-dependent channel dictionary matrix by considering propagation characteristic interested...

The wireless communication systems based on Unmanned Aerial Vehicles (UAVs) have found a wide range of applications recently. In this paper, we propose new three-dimensional (3D) non-stationary multiple-input multiple-output (MIMO) channel model for the links between UAV and mobile terminal (MT). originates traditional geometry-based stochastic models (GBSMs) but considers propagation environment due to rapid movements UAV, MT, clusters. Meanwhile, upgrade time evolving algorithms...

Unmanned aerial vehicle (UAV) aided millimeter wave (mmWave) technologies have a promising prospect in the future wireless communication networks. By considering factors of three-dimensional (3D) scattering space, 3D trajectory, and antenna array, non-stationary ray-based channel model for UAV-to-vehicle (U2V) mmWave communications is proposed. The computation generation methods parameters including inter-path intra-path are developed illustrated detail. calculated deterministic way based on...

Line-of-sight (LoS) path is essential for the reliability of air-to-ground (A2G) communications, but existence LoS difficult to predict due random obstacles on ground. Based statistical geographic information and Fresnel clearance zone, a general stochastic probability model three-dimensional (3D) A2G channels under urban scenarios developed. By considering factors, i.e., building height distribution, width, space, carrier frequency, transceiver's heights, proposed suitable different...

Unmanned aerial vehicles (UAVs) with multi‐input–multi‐output technologies are considered as a promising platform to provide future high‐speed wireless communication services. In this study, considering three‐dimensional (3D) antenna arrays and 3D arbitrary trajectories of the UAV mobile terminal, authors propose new non‐stationary geometry‐based stochastic channel model for UAV‐ground systems. Under non‐isotropic scattering scenarios, computation optimisation methods time‐variant parameters...

Since the environment for CBM development in China has been changing recent years, it is necessary to re-consider relevant strategies. Through investigations, surveys, geologic assessment, strategic decision-making and other techniques, strategies were discussed respect present situations, opportunities, challenges, proved reserves, producing principles, countermeasures, time-spatial allocation of strategies, risk assessments, elimination risks. Some research results obtained. Firstly, still...

In this paper, a multi-hop relay channel model based on unmanned aerial vehicles (UAVs) is established by taking into account of the propagation loss, shadowing, and multi-path fading. Based proposed model, cascaded loss link probability density function (PDF) fading are derived. Moreover, theoretical performance UAV-based system, i.e., outage probability, bit error rate (BER), capacity, also analysed Simulation results show agreement with for hill, mountain, sea scenarios, indicating...

Millimeter wave (mmWave) communications of unmanned aerial vehicles (UAVs) have drawn dramatic attentions for its flexibility on a variety applications. Recently, channel tracking base the spatial features has been proposed to solve problem beam misalignments due UAV navigation. However, unstable pointing caused by non-ideal environment may impact performance mmWave systems significantly. In this paper, an improved beamforming method is presented overcome shortcoming. Firstly, effect...

To address the issue of limited application scenarios associated with connectivity assurance based on two-dimensional (2D) trajectory planning, this paper proposes an improved deep reinforcement learning (DRL) -based three-dimensional (3D) planning method for cellular unmanned aerial vehicles (UAVs) communication. By considering 3D space environment and integrating factors such as UAV mission completion time connectivity, we develop objective function path optimization utilize advanced...

In this paper, we propose a new three-dimensional (3D) channel model for the millimeter wave (mmWave) communication links between Unmanned Aerial Vehicle (UAV) and vehicle. The applies ray tracing (RT) theory in traditional geometry-based stochastic (GBSM), it also takes specific features of mmWave propagation into account. Meanwhile, time evolving algorithms parameters, i.e., distance, angles, path delays, powers are analyzed illustrated. On these basis, simulations at 28 GHz conducted...

Dual-functional radar and communication (DFRC) techniques are promising in the next generation wireless network. An intelligent reflecting surface (IRS) can improve energy efficiency (EE) of DFRC system, which is crucial importance practical applications. However, EE achieved by using sum-rate be limited channel conditions performance requirement. Thus, this paper, maximization problem studied an IRS-assisted system. The maximized jointly optimizing transmit beamforming IRS phase shift...

By considering the 3-D antenna arrays and arbitrary trajectories of a mobile station, generic non-stationary geometry-based stochastic model for multiple-input multiple-output channels is proposed. Under non-isotropic von Mises-Fisher scattering scenarios, theoretical approximate expressions time-variant spatial correlation function (SCF) are also derived analyzed. Simulation results show that SCFs proposed match well with ones existing models special cases 1-D linear 2-D curve trajectories....

To overcome the mutual coupling (MC) of multiple antennas in millimeter wave (mmWave) communication systems, a novel beam design method with low complexity is proposed this paper. Firstly, an equivalent channel model incorporating effect MC analyzed and established, then optimal precoding / combiner vector for beamforming derived. On basis, by using greedy geometric (GG) algorithm, hybrid proposed. Finally, performance compared other traditional ones. The simulation results show that has...

Abstract Traditional methods to generate non-thermal Ar-N2 plasma at low pressure conditions have predominantly utilized radiofrequency (RF) and direct current (DC) power supplies. These techniques proven efficiency in various applications, including surface modification microbial decontamination. However, high operational costs the complex equipment provoked interest alternative approaches. This study investigates characteristics efficacy of generated under vacuum using a low-frequency AC...

By taking into account moving scatterers and velocity variations of terminals, a non-stationary vehicle-to-vehicle (V2V) channel model under non-line-of-sight (NLoS) scenarios is proposed. Under 2D non-isotropic scattering scenarios, the closed-form expression time-variant temporal correlation function (TCF) for proposed derived analyzed. The general solution includes most existing results as special cases, i.e., stationary constant velocities or fixed scatterers. In addition, TCF has good...

Based on the geometry and ray tracing (RT) theory, a millimeter wave (mmWave) channel model parameter computation method for unmanned aerial vehicle (UAV) assisted air-to-ground (A2G) communications are proposed in this paper. In order to speed up calculation, reconstruction process of scene database original digital map is developed. Moreover, effects accuracy characteristic analyzed by extensive simulations at 28 GHz under campus scene. The simulation analysis results show that simplified...

Considering the three-dimensional (3D) trajectory, 3D antenna array, and beamforming of unmanned aerial vehicle (UAV), a novel non-stationary millimeter wave (mmWave) geometry-based stochastic model for UAV to communication channels is proposed. Based on analysis results measured ray tracing simulation data mmWave links, proposed parametric channel constructed by line-of-sight path, ground specular two strongest single-bounce paths. Meanwhile, new parameter computation method also developed,...

Abstract Cellular-connected unmanned aerial vehicles (UAVs), which have the potential to extend cellular services from ground into airspace, represent a promising technological advancement. However, presence of communication coverage black holes among base stations and various obstacles within domain pose significant challenges ensuring safe operation UAVs. This paper introduces novel trajectory planning scheme, namely double-map assisted UAV approach, leverages deep reinforcement learning...

In order to improve the energy efficiency (EE) in cognitive radio (CR), a joint optimal energy-efficient cooperative spectrum sensing (CSS) and transmission multi-channel CR is proposed this paper. EE described as tradeoff between throughput entirely consumed power. A optimization problem formulated maximize by jointly optimizing local time, number of secondary users (SU), bandwidth combined algorithm bi-level optimization, Polyblock Dinkelbach's solve non-convex effectively. The simulation...

Frame and frequency synchronization are essential for orthogonal division multiplexing (OFDM) systems.The frame offset owing to incorrect start point position of the fast Fourier transform (FFT) window, carrier (CFO) due Doppler shift or mismatch between transmitter receiver oscillators, can bring severe intersymbol interference (ISI) inter-carrier (ICI) OFDM system.Relying on relatively good correlation characteristic pseudo-noise (PN) sequence, a joint normalized CFO estimation algorithm...

For the unmanned aerial vehicle (UAV) communication scenarios, time-varying fading characteristics cased by three-dimensional(3D) scattering environment and 3D trajectory have an important impact on establishing reliable link. In this paper, a generic non-stationary geometry-based stochastic model (GBSM) for UAV channels is developed. Different from traditional GBSMs, proposed takes arbitrary trajectories of into account. On basis, two second-order statistical properties envelope, i.e.,...