Simulation Of Communication Systems Research Articles

A Wireless Communication System for Urban Water Supply Networks Based on Guided Acoustic Waves

The structural complexity of real-world pipeline networks makes it difficult to derive physics-based models of acoustic propagation. This work deals with the design of a communication system based on the propagation of acoustic waves in water-filled pipes. A method based on the experimental characterization of the communication channel is proposed. This approach is applied to an urban water distribution pipeline, and a black-box model representing its frequency response is obtained. The derived two-port model is used for the simulation of a complete communication system, comprising transmitter and receiver models, with the aim of using the water pipe as a wireless communication channel. It is shown that the choice of modulation parameters is critical in order to deal with issues such as the frequency selectivity of the channel and multipath wave propagation. A communication system is presented and the experimental results of the communicated data are provided.

K-means Cluster Algorithm Applied for Geometric Shaping Based on Iterative Polar Modulation in Inter-Data Centers Optical Interconnection

The demand of delivering various services is driving inter-data centers optical interconnection towards 400 G/800 G, which calls for increasing capacity and spectrum efficiency. The aim of this study is to effectively increase capacity while also improving nonlinear noise anti-interference. Hence, this paper presents a state-of-the-art scheme that applies the K-means cluster algorithm in geometric shaping based on iterative polar modulation (IPM). A coherent optical communication simulation system was established to demonstrate the performance of our proposal. The investigation reveals that the gap between IPM and Shannon limit has significantly narrowed in terms of mutual information. Moreover, when compared with IPM and QAM using the blind phase searching under the same order at HD-FEC threshold, the IPM-16 using the K-means algorithm achieves 0.9 dB and 1.7 dB gain; the IPM-64 achieves 0.3 dB and 1.1 dB gain, and the IPM-256 achieves 0.4 dB and 0.8 dB gain. The robustness of nonlinear noise and high capacity enable this state-of-the-art scheme to be used as an optional modulation format not only for inter-data centers optical interconnection but also for any high speed, long distance optical fiber communication system.

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.

Simulations of vehicular optical wireless communication systems and comparisons with DSRC systems.

Optical wireless communication (OWC) has been proposed as a complementary technique to radio frequency (RF) communications for vehicular applications. OWC systems can be categorized into two types based on the transmitters: the first one is the light-emitting diode (LED)-based OWC system, and the second is the laser diode (LD)-based OWC system. Simulations of both types of OWC systems are presented in this paper. To simulate the OWC systems precisely, outdoor experiments of OWC systems have been done and the measurements of background noise are applied in the simulations. In terms of the LED-based OWC system, the impulse responses are obtained by an improved ray tracing algorithm. To reduce the computational complexity, visibility graphs are applied in the improved ray tracing algorithm. Compared with the brute force algorithm, our improved algorithm is able to reduce the computational complexity from O(n3) to O(n2log⁡(n)), where n is the number of mobile terminals. In LD-based OWC systems, the performance and stability are highly dependent on the tracking system in vehicular applications. Therefore, this paper also analyzes the requirements of tracking accuracy in LD-based OWC systems. Finally, the simulated LED-based OWC system is compared with the dedicated short-range communication (DSRC) system under different traffic densities. Our experimental and simulation results have demonstrated that OWC can be a complementary technique for DSRC under conditions of high traffic density.

Tactical Communications between Military Vehicles

The increasing evolution and development of telecommunications as well as the need for wider bandwidths to comply with the users’ needs, has led to the development of the so-called free space optical communications. The advantages of optical communications in comparison to radio frequency communications draw interest for certain military applications.
 This paper describes the simulation, development and implementation of an optical communication system which integrates the various functional blocks of the optical emitter and the optical receiver and presents some theoretical considerations about the specific characteristics of the propagation of the optical signals in free space. The implementation of this system in military vehicles to allow wider bandwidth in military communications, as well as to function as an alternative system to the used systems, is one of the objectives of this dissertation.
 For this purpose, two circuits (emitter and receiver) were projected and designed including the design of printed circuit boards (PCB) and performed some simulations of the optical part of the complete system and the electronic simulation of some parts of the electronic circuits.

Construction and 3D Simulation of Virtual Animation Instant Network Communication System Based on Convolution Neural Networks.

In recent years, great progress has been made in 3D simulation modeling of instant network communication system, such as the application of virtual reality technology and 3D virtual animation online modeling technology. Facing the increasing demand of different industries, how to build an instant network communication system for 3D virtual animation has become a research hotspot. On this basis, the construction method of fast instant network communication system based on convolutional neural network and fusion morphological 3D simulation model is studied. This paper analyzes the research status of instant network communication system. The experiment optimizes and improves the shortcomings of the current research hotspot of virtual animation instant network communication system and takes the morphological 3D simulation model fusion as the core for in-depth optimization. Finally, the experimental results show that the fusion morphological 3D simulation model can reconstruct the standard 3D virtual animation model according to different needs and can quickly model the optimization strategy according to the local differences of different animations. The response accuracy of the network communication system reaches 97.7%.

Research on Simulation Teaching of Communication System in Higher Vocational Education Based on MATLAB

With the rapid development of modern computer science and technology, a new generation of visual simulation software MATLAB has been developed. These powerful simulation software make the design and analysis of communication system simulation relatively intuitive and convenient, which also makes the communication system simulation technology get faster development. Through the dynamic simulation environment of MATLAB/Simulink, we can build a digital communication system simulation platform for design and simulation, which fully shows the importance of MATLAB/Simulink in the communication system. This paper mainly analyses the application of MATLAB in communication system simulation. Then this paper analyses the basic principle of DSB signal, the simulation of modulation signal based on M file and the mdl file.

Research on simulation technology of Shipborne Satellite Communication System

In this paper, aiming at the architecture, key technologies and member functions of the simulation of the onboard satellite system, a simulation federate model with good hierarchical structure is designed, and a satellite communication simulation system based on HLA is constructed. The key problems such as time unification, fault simulation and real-time visual display are solved. Through the functional simulation of the operation process of the Shipborne Satellite Communication System in the distributed virtual simulation environment, the results show that the system has good interactivity and scalability, and is an effective means to test the reliability of equipment and reduce the risk of scientific test.

МЕТОД МАСШТАБНОГО ФИЗИЧЕСКОГО МОДЕЛИРОВАНИЯ СИСТЕМЫ СВЯЗИ УФ-С ДИАПАЗОНА

Communication systems of the solar-blind ultraviolet range UV-C from 200 to 280 nm enable communication in the absence of line of sight due to the strong scattering of UV radiation in the atmosphere. Creating a full-scale model of the UV communication system at the initial stage of technical implementation can be extremely difficult due to the high requirements for the components of the optical receiver and transmitter. An urgent task is to develop a technique for large-scale physical modeling of the UV-C coupling system, which allows evaluating the performance of the system under new conditions with new components based on experimental results obtained for initial conditions with initial components. Based on the analytical model of the UV communication system, a signal-to-noise ratio (SNR) conversion coefficient is introduced in the new system compared to the original one. The simulation of the UV communication system with varying light levels and the solar-blind filter model showed the effectiveness of the proposed method for simplifying the implementation of the UV communication system.

Simulation Study of DP-QPSK Coherent Detection Transmission System Based on Optisystem

Dual polarization quadrature phase shift keying (DP-QPSK) is currently the main modulation format for high-speed optical fiber communications, and its simulation modeling has important implications for theoretical research and practical applications. Based on Optisystem 15 optical communication system simulation software, this paper builds a 100 Gbit/s rate DP-QPSK modulation format coherent optical transmission system simulation model, analyzes the working principles of the transmitting end, transmission link, and coherent receiver. The principle of signal recovery at the digital signal processing end is briefly explained. The simulation results show that the signal quality after DSP processing has been significantly improved.

광학 카메라 통신 시스템의 현실적 시뮬레이션 프레임워크

광학 카메라 통신 (OCC)에서 LED 어레이는 카메라가 수신 할 가시광 신호를 전송하는 데 사용된다. OCC 시스템의 성능은 LED 휘도, 배경 조도, 카메라 노출 설정, LED 및 카메라 이동 속도 등 통신 채널의 많은 매개 변수에 따라 달라진다. 이러한 많은 매개 변수의 영향을 체계적으로 조사하려면 OCC 시스템에 대한 시뮬레이션이 필수적이다. 본 연구에서는 광도 측정, 카메라 형상, 디지털 이미지 획득 및 광학 이미지 통신을 포함한 여러 분야의 기본적인 원리에 대해 서술하고, OCC 시스템을 분석하기 위한 요구 사항을 살펴본다. 이러한 원리와 요구사항에 따라 OCC 시스템의 현실적인 시뮬레이션을 위한 프레임워크를 제안한다.

Performance of LTE downlink communication system in presence of electronic warfare spot jamming

Wireless communication is one of the principally active zones of tools development and has become necessary part of everyday life. Simulation of wireless communication systems accurately is very important for predicting its performance under different scenarios. Long-Term Evolution (LTE) is named by next generation wireless communications. It is a standard for high-speed wireless communication for mobile phones and data terminals. In this paper, the performance of standard single-input-single-output (SISO) LTE Frequency Domain Duplex (FDD) downlink (DL) signal in additive white Gaussian noise (AWGN) channel is evaluated in two scenarios without jamming and in presence of electronic warfare spot jamming. Firstly, the performance of the standard LTE communication system in absence of jamming is investigated by calculating the probability of Bit Error Rate (BER) and Frame Error Rate (FER) versus Signal Noise Ratio (SNR). Secondly, the performance in presence of electronic warfare spot jamming scheme is investigated by constant Jamming to Signal Ratio (JSR) and different values of the normalized jamming bandwidth. In order to illustrate the impact of jamming on the standard LTE DL wireless communication system, the measurement is evaluated by using the aid of SystemVue software program.

Performance Analysis of VLC Based on 802.11ac Frame Structure

Visible light communication (VLC) has gained tremendous attention recently as it possesses prominent features to address the limitations imposed by current wireless technologies, such as high capacity, high spectral efficiency, high energy efficiency, low battery consumption, and low latency. In this letter, we have designed a packet-based VLC protocol based on the IEEE 802.11ac frame structure, which can be utilized for the simulation, analysis, and testing of a wireless VLC communication system. Our evaluation is based on the channel impulse responses (CIRs) provided by the IEEE task group for the 802.15.7r1 standard, where we estimate the channel based on the legacy fields and then compare the performance of wireless VLC with a radio frequency (RF) 802.11ac-based wireless local area network (WLAN). We demonstrate in this letter that the VLC can be comfortably incorporated with the already existing communication standards and is also capable of providing equal performance as that of the 802.11ac.

Generation of Synthetic Network Traffic Series Using a Transformed Autoregressive Model Based Adaptive Algorithm

Modeling, testing and simulation of communications systems require to generate synthetic traffic series that present characteristics and behaviors as similar as possible to those of real network traffic traces. In this paper, we propose an adaptive algorithm to estimate the parameters of the Transformed Autoregressive Moving Average (TARMA) model in order to capture the autocorrelation function and the cumulative density function of the desired network traffic trace. Different from other works involving TARMA, we consider the adaptive estimation of its parameters. We compare the performance of the proposed on-line modeling approach to those of the Autoregressive Moving Average Model (ARMA) and of the on-batch Transformed Model in terms of mean, variance, moments, autocorrelation and probability density function. A transmission link composed of a single server with buffer is also simulated, which proves the efficiency of the proposed model in describing real traffic traces. The simulations carried out in this work show that the adaptive TARMA model outperforms in general the other considered autoregressive models.

Modelling and Simulation of Pseudo-Noise Sequence-Based Underwater Acoustic OSDM Communication System

Orthogonal signal division multiplex (OSDM) is an emerging signal modulation technology which has a lower peak-to-average power ratio (PAPR) and a flexible subcarrier system architecture. Particularly, it can be seen as a bridge between the single-carrier modulation and the orthogonal frequency division multiplexing (OFDM) modulation in the frequency domain. Aiming at the development trend and demand of underwater acoustic hybrid and adaptive modulation communication technology, a pseudo-noise (PN) sequence-based underwater acoustic OSDM communication system is proposed in this paper. A data frame structure with PN sequence is designed to solve the multipath and Doppler effect of underwater acoustic channel. On the basis of the PN sequence, a compressive sensing method based on the orthogonal matching pursuit (OMP) algorithm and the minimum mean square error (MMSE) algorithm is designed for channel estimation and equalization. On the basis of the system construction, the relationship among the OSDM vector length M, the OSDM subcarrier number N, and the underwater acoustic channel length is further studied for adaptive modulation of underwater acoustic communication. Finally, the proposed system is verified by simulation. The OSDM system has lower and controllable PAPR. When the OSDM vector length M is bigger than the channel length, and the system subcarrier flexibility is guaranteed, the bit error rate (BER) of the OSDM system is lower than that of the OFDM system and the single-carrier system. The PN sequence-based compressive sensing channel estimation and equalization with the OMP and MMSE algorithms has a good performance to resist the multipath effect of underwater acoustic channel.

Traffic simulation of broadband LEO constellation satellite communication system

Traffic simulation of broadband LEO constellation satellite communication system

Multiuser wireless channel simulation for communication systems with nonparametric reception

When combined with error-correction codes reception techniques based on nonparametric hypothesis testing and order statistics provide strong immunity to different types of interference including multiuser interference. That makes communication systems using such reception techniques most appealing candidates for various applications such as Machine-to-Machine (M2M) communications and Internet Of Things (IOT). Unfortunately analytical treatment of communication systems with nonparametric reception remains a cumbersome task. Therefore simulation remains the main tool for the development of such systems. For multiuser systems supporting hundreds of active users and operating in fading channels (e.g. IOT) time spending grows drastically hampering the design process. Thus the development of simplified multiuser channel models is of great interest. In this paper two simplified mathematical models of multiuser interference for the case of a single user nonparametric reception are proposed. The effectiveness of the proposed models is compared by means of modulation. Special attention is paid to the problem of software implementation of the models proposed.

Свойства временных оптических солитонов в оптических волокнах и возможность их использования в телекоммуникациях. Часть 4

In the fourth part of the paper, a theoretical study of the processes of propagation of pulses having the form of Gaussian functions and hyperbolic secant on a single-mode optical fibers with alternating signs of group velocity dispersions and taking into account losses was performed. Fundamental inaccuracies in widely used expressions to describe the processes of propagation of Gaussian pulses through optical fibers are revealed and refined analytical expressions are proposed. The paper contains a simulation of optical fiber communication systems at speeds of 10 and 40 Gbit/s using the OptiSystem and AltPhotonic Simulation Tool programs. The influence of the chirping value on the quality of communication is investigated. A comparison of fiber-optic communication systems using concentrated and distributed optical amplifiers is performed. Engineering formulas and recommendations for designing quasi-soliton optical fiber communication systems are proposed.

Modeling and simulation of quantum information, quantum communication, and quantum key distribution (QKD) systems

Modeling and simulation of quantum information, quantum communication, and quantum key distribution (QKD) systems

OVERVIEW OF ELECTROMAGNETIC INTERFERENCE ISSUES IN AIRCRAFT

Purpose of Study: In the modern era, due to several conflictions or uncertainty in the aircraft, Electromagnetic Interference (EMI) or Radio Frequency Interference (RFI) issues occurred, frequently. The main reason behind it several disturbances generated by an external source that imitate wireless circuits with the help of conduction, electrostatic coupling, and electromagnetic induction. These disturbances may decrease the performance of the circuits or sometimes fully stop the operations.
 Methodology: The main challenges in EMI are modeling and simulation for modern and future wireless communication systems and networks taking into account nonlinear interference effects.
 Result: In this paper, overviews of several issues of EMI or RFI are illustrated.