Wireless Communication Channel Model Research Articles

A GAN-GRU Based Space-Time Predictive Channel Model for 6G Wireless Communications

A GAN-GRU Based Space-Time Predictive Channel Model for 6G Wireless Communications

A General Physics-Based IRS Auxiliary Channel Model for Wireless Communications

A General Physics-Based IRS Auxiliary Channel Model for Wireless Communications

Cluster control technology of transmission line intelligent inspection drones based on 5G communication

Abstract This paper firstly analyzes the network topology model of the UAV cluster network and wireless 5G communication channel model by modeling and briefly analyzes the idea of topology movement control for flying self-organized networks. Then, a cluster-based structure and reinforcement learning clustered routing protocol is proposed for the problem of easy breakage of routing forwarding paths caused by smart inspection of transmission lines based on UAV clusters for 5G communication. Finally, a cluster structure-based precedence routing protocol is designed, an adaptive routing protocol based on location and link quality Q-learning is used between clusters, and fast and reliable routing is achieved by combining the routing table maintained by itself. The simulation results show that ARP-L-Q (average end-to-end delay 4.22, average packet loss rate 88.09%, average packet rate 2.37, average control overhead 2.52) protocol performs better than GPSR and GACB protocols, and the experiment verifies that ARP-L-Q protocol can better achieve the high dynamic reconfiguration, high stability and reliability, and low communication delay of UAV cluster-based 5G communication network. Characteristics and requirements. This study has application prospects in both civil emergency and military mobile communication and has certain military significance, theoretical value and application value for thus promoting UAV innovation.

Errorless Underwater Channel Selection Scheme Using Forward Error Rectification and Modulation

Acoustic and optical communication are the best options for data transmission in underwater communication. This paper presents the simulation model of an underwater wireless optical communication channel using the Errorless Channel Selection Using Forward Error Rectification and Modulation Progression (ECFM). The suitable modulation methods are used to encode and transfer the packets properly, the data is encoded in differential phase shift key mode at the phase of the light wave carrier. In addition, to send and receive data, an error rectification method is developed in the transport layer, which improves network speed. In addition, we create connections by observing the impact of the refractive index of the optical channel and the reflections formed on the surface of the water. As well as the distance the data travels, throughput, packet delivery ratio, energy consumed, and delay are calculated and discussed using a network simulator. We also look at the losses caused by the operation of the channels running on the network and its location points.

Geometry-Based Channel Modelling for Vehicle-to-Vehicle Communication: A Review

Vehicle-to-Vehicle (V2V) communication has received a lot of attention over recent years since it can improve the efficiency and safety of roads for drivers and travellers besides other numerous applications. However dynamic nature of this environment makes it difficult to come up with a suitable wireless communication channel model that can be used in the simulation of any V2V communication system. This paper reviews the recent techniques used for geometry-based stochastic channel modelling for V2V communication. It starts by presenting the various classes of wireless communication channel models available in the literature with more emphasis on the Geometry-Based Stochastic channel Models (GBSM). Then the paper discusses in more detail the state of the art of the regular-shaped and irregular-shaped GBSM for the two- and three-dimensional models. Finally, main challenges are identified and future research directions in this area are recommended.

Beyond 5G for digital twins of UAVs

The purpose is to explore the application effects and limitations of Unmanned Aerial Vehicle (UAV) in 5G/B5G (Beyond 5G) mobile and wireless communication. Based on 5Gcommunication, the deep learning (DL) algorithm is introduced to construct the UAV Digital Twins (DTs) communication channel model based on DL. The Coordinated Multi-point Transmission (COMP) technology is adopted to study the interference suppression of UAVs. The key algorithm in the physical layer security is employed to ensure information communication security. Finally, the model constructed is simulated and analyzed. The transmission error rates and transmission estimation accuracy of several algorithms, including the proposed algorithm and ordinary Deep Neural Networks (DNNs), are compared under different Signal-to-Noise Ratios (SNRs). Results find that the convergence speed and convergence effect of the proposed algorithm has prominent advantages, presenting strong robustness; the proposed algorithm's estimation accuracy is about 150 times higher than the traditional algorithms. Further analysis reveals that the proposed algorithm's accuracy reaches 82.39%, which increases by at least 3.2% than other classic machine algorithms. The indicators of Precision, Recall, and F1 are compared as well. Apparently, the Precision, Recall, and F1 values of the proposed algorithm are the highest, while the transmission delay is the smallest. Therefore, the constructed UAV DTs wireless communication channel model has strong robustness and further reduces UAV limitations, providing a reference for improving UAV system performance in the later stage.

Advanced modulation coding schemes for an optical transceiver systems–based OWC communication channel model

This paper examines advanced modulation coding schemes for an optical transceiver systems–based optical wireless communication (OWC) channel model. These modulation techniquesinclude On-Off keying and return to zero (RZ)/non–return to zero (NRZ) coding. The signal power level against time and frequency spectral variations are measured. The max. Q factor and min. bit error rate (BER) are estimated and clarified for each modulation code scheme by using an optisystem simulation model. Transmission bit rates of up to 40 Gb/s can be achieved for possible distances up to 500 km with acceptable Q factor. The received power and max. Q factor are measured and clarified with OWC distance variations. The On-Off keying modulation code scheme resulted in better performance than the other modulation code schemes did.

Dual Pilot Scheme (DPS) and Its Application in Massive MIMO

The pilot scheme currently used in 5th generation (5G) cellular networks assigns the same set of orthogonal pilot signals to all cells. This results in inter-cell interference, also known as pilot contamination , which can significantly degrade performance, especially in massive multi-input multi-output (MIMO) systems. To mitigate this interference, we propose a novel Dual Pilot Scheme (DPS) that assigns a slightly modified set of nearly-orthogonal pilot signals. DPS is a general scheme that can be implemented in any wireless communication system, including 5G and beyond. We demonstrate the integration of DPS in a massive MIMO system in both microscopic and macroscopic levels and analytically prove that DPS enables more accurate estimates of the channel state information in the minimum mean-squared error sense, under the independent identically distributed (i.i.d.) and the correlated Rayleigh fading wireless communication channel models. We further validate and demonstrate the advantages of DPS over various channel models of massive MIMO 5G technology by extensive simulations.

Indoor Optical Wireless Communication Channel Models

Indoor Optical Wireless Communication Channel Models

Characterization of path loss model for wireless communication channel modelling

PurposeWireless communication channel provides a wide area of applications in the field of communication, distributed sensor network and so on. The prominence of the wireless communication channel is because of its robust nature and the sustainability for the precise ranging and the localization. The precision and accuracy of the wireless communication channel largely depend on the localization. The development of the wireless communication channel with improved benefits needs the accurate channel model.Design/methodology/approachThis paper characterizes the tangential path loss model in the WINNER based wireless communication channel model. The measurements taken in the WINNER channel model are compared with the tangential path loss characterized WINNER Channel model.FindingsThe model operates well over the varying antenna orientations, measurement condition and the propagation condition. The proposed tangential path loss model is performing well over the various outdoor scenarios.Originality/valueThe proposed characterization shows change in the small-scale parameters (SSP), such as power, delay, angle of arrival and angle of departure as well as the large-scale parameters (LSP), such as RMS delay spread, shadowing, path loss and Ricean factor associated with the model.

Capacity Maximized Linear Precoder Design for Spatial-Multiplexing MIMO VLC Systems

This paper proposes a novel linear precoder design based on the singular value decomposition (SVD) for multi-input multi-output visible light communications (MIMO VLC). We provide an analytical expression on power allocation subject to the function of maximizing the lower bound of capacity according to the optical wireless communication channel model. The expression is rather different from the radio frequency (RF) communications due to the non-negativity of the transmitted signals in VLC. Furthermore, we design an adaptive bit loading scheme for sub-streams with consideration of the tremendous gain difference among subchannels. Performances of the proposed adaptive power and bits allocation strategy are evaluated in two traditional MIMO VLC scenarios, i.e., a practical $2\times 2$ indoor scenario and a classical $4\times 4$ system that is generated according to the MIMO model. In simulations, the techniques of unipolar M -level pulse amplitude modulation ( M -PAM) and spatial-multiplexing (SMP) are employed, and the performance comparison with other SVD-based linear precoders is also given. Simulation results show that the proposed approach can effectively improve the spectral efficiency and guarantee the bit error rate (BER) performance under the same constraints of aggregate optical power budget and non-negativity included by the intensity modulation. It indicates that the strategy of uneven bits and power allocation with full consideration of the ill-conditioned characteristics of subchannels performs better than that based on equal bits transmission in VLC systems.

Optical chaotic secure algorithm based on space laser communication

The traditional drive response synchronization control method has the poor robustness, which results in the low security performance of the optical chaotic secure communication. To address this problem, an optical chaotic secure algorithm based on space laser communication is proposed in this paper. With the advantage of space laser communication and full consideration of the influence of complex environment on signal transmission of laser wireless communication, a laser wireless communication channel model is built. Based on this, a hybrid self-synchronization chaotic system model is proposed. It can reduce the information needed for transmission, and only need to transmit a small amount of error correction signals on the channel to achieve synchronization of the receiving and the transmitting system, which greatly suppress the drawback of the traditional method. On the basis of chaotic synchronization, the erbium-doped fiber laser is used for information transmission. Different encryption techniques are used to achieve optical chaotic secure communication within the allowable range of error. Numerical simulation results show that the proposed algorithm has good security and robustness, and can realize the secure communication for different signals.

Optical Wireless Communication Channel Measurements and Models

Optical wireless communications (OWCs) refer to wireless communication technologies which utilize optical carriers in infrared, visible light, or ultraviolet bands of electromagnetic spectrum. For the sake of an OWC link design and performance evaluation, a comprehensive understanding and an accurate prediction of link behavior are indispensable. Therefore, accurate and efficient channel models are crucial for the OWC link design. This paper first provides a brief history of OWCs. It also considers OWC channel scenarios and their utilization trade-off in terms of optical carrier, range, mobility, and power efficiency. Furthermore, the main optical channel characteristics that affect the OWC link performance are investigated. A comprehensive overview of the most important OWCs channel measurement campaigns and channel models, primarily for wireless infrared communications and visible light communications, are presented. OWCs channel models are further compared in terms of computation speed, complexity, and accuracy. The survey considers indoor, outdoor, underground, and underwater communication environments. Finally, future research directions in OWCs channel measurements and models are addressed.

Physical-Statistical Channel Model for Off-Body Area Network

In this letter, a physical-statistical-based channel model for off-body wireless communications is presented. The model utilizes a dynamic human walking model, which provides detailed description of the movement of the different body parts. The received signal is composed of a direct component, which might be subject to shadowing by the body parts, and a multipath component due to reflections from the environmental scatterers. The uniform theory of diffraction (UTD) is utilized to accurately calculate the time-varying shadowing and scattering effects of the direct signal due to the moving of body parts. A Rayleigh distribution is used to represent the multipath fading effects by the scatterers around the human body. The model is validated in terms of first- and second-order statistics using 2.36 GHz measurement data, showing good agreement.

Multipath Channel Model for Radio Propagation over Sea Surface

When radio signal propagates over the sea, the reflection of sea surface and the scattering of sea waves result in multipath components of the transmitted signal at the receiver. This paper introduces an analytical approach for developing multipath channel model for maritime wireless communications over sea. The presented modeling approach can establish the channel impulse response consisting of specular multipath and diffuse multipath produced by smooth sea surface and rough sea surface, respectively. Specifically, the diffuse multipath is obtained by accumulating diffuse scattering energy from the glistening surface. The methods for deriving specular multipath and diffuse multipath are given in detail. Finally, the numerical results of multipath channel models under different transmission conditions are obtained and analyzed using the introduced channel modeling approach.

Impact Analyses of High-Order Light Reflections on Indoor Optical Wireless Channel Model and Calibration

This paper analyzes the impact of high order light reflections on indoor optical wireless communication (IOWC) channel models. Based on observing the results of computer simulations, a calibration method is proposed to reduce model errors. Channel models are generated by tracing and adding up diffuse light reflections and sequential sub-reflections along its traveling path. As computation complexity increases significantly with the number of reflection orders considered, researchers traditionally, though incorrectly, take the contribution of first a few reflection orders, most commonly three, to represent the complete channel. Discarded high-order reflections bring no significant performance difference to low-speed transmission systems; however, major contemporary IOWC research institutions focus on high-speed Gigabits per second (Gbps) communications and the model errors resulting from discarded high-order reflections are no longer negligible. This is where the importance of our proposed method lies. root-mean-square (RMS) delay-spread, for instance, is severely underestimated by neglecting higher-order reflections. We simulate an IOWC system in an ordinary 6 m × 6 m × 3 m room and calculate the contributions of each order of reflections at 841 locations. It shows the RMS delay-spread estimation using the first three orders underestimates the true value by 15.3% on the average and by at most 26.6% as maximum. To limit error within half a symbol period, 1 Gbps and 10 Gbps systems tolerate underestimations up to 13.7% and 1.4%, respectively. These must be achieved by applying first five and nine orders. To maintain the computation efficiency of low-order reflection models and improve their accuracies, we propose a statistical calibration method. It reduces average model error of first three reflection orders from 15.7% to 4.3%. The numbers of orders required by 1 and 10 Gps systems are individually reduced to 3 and 7.

Time-varying on-body wireless channel model during walking

A novel dynamic channel model for on-body wireless communication during walking is proposed. The developed model utilizes a human walking model which provides detailed information on the movement of the human body parts. The diffraction of the signal around the body parts is used to describe the time-varying shadowing effects. Body part movements are also used to estimate the signal fading caused by angular variations of the transmitting and receiving antenna gains. A Rice distribution is used to represent the multipath fading effects caused by objects around the human body. Simulation results of the first- and second-order statistics of the received signal affected by moving body parts for 2.4 GHz signal are presented. To illustrate the capabilities of the developed model, time series were generated and used in system performance calculations. The obtained results give an insight into the potential advantages of link diversity technique in wireless body area networks (WBANs).

THE ANALYSIS OF PHYSICAL PROPERTIES OF THE ULTRA-WIDEBAND CHANNEL MODEL IN COMMUNICATION AT SHORT DISTANCES

Accurately modeling the channel is extremely important for the design of communication systems. Knowledge of the key features of the channel provides the designers with the ability to predict performance of the system for specific modulation, channel coding, and signal processing. In this paper, we will present the analysis of physical properties of the UWB channel model and propose an UWB channel model for short distance wireless communications (with a comparison to the IEEE 802.15.3a channel model). Through the analysis and design, conclusions related to the UWB channel model were drawn as follows: there are reflection, diffraction, multipath transmission, and signal attenuation with distance and frequency but there is no pulse distortion.

Application-Oriented Finite Sample Experiment Design: A Semidefinite Relaxation Approach

In this paper, the problem of input signal design with the property that the estimated model satisfies a given performance level with a prescribed probability is studied. The aforementioned performance level is associated with a particular application. This problem is well-known to fall within the class of chance-constrained optimization problems, which are nonconvex in most cases. Convexification is attempted based on a Markov inequality, leading to semidefinite programming (SDP) relaxation formulations. As applications, we focus on the identification of multiple input multiple output (MIMO) wireless communication channel models for minimum mean square error (MMSE) channel equalization and zero-forcing (ZF) precoding.

Statistical mechanical analysis of the Kronecker channel model for multiple-input multiple-output wireless communication

The Kronecker channel model of wireless communication is analyzed using statistical mechanics methods. In the model, spatial proximities among transmission/reception antennas are taken into account as certain correlation matrices, which generally yield nontrivial dependence among symbols to be estimated. This prevents accurate assessment of the communication performance by naively using a previously developed analytical scheme based on a matrix integration formula. In order to resolve this difficulty, we develop a formalism that can formally handle the correlations in Kronecker models based on the known scheme. Unfortunately, direct application of the developed scheme is, in general, practically difficult. However, the formalism is still useful, indicating that the effect of the correlations generally increase after the fourth order with respect to correlation strength. Therefore, the known analytical scheme offers a good approximation in performance evaluation when the correlation strength is sufficiently small. For a class of specific correlation, we show that the performance analysis can be mapped to the problem of one-dimensional spin systems in random fields, which can be investigated without approximation by the belief propagation algorithm.