Performance analysis of mobile nodes in ad hoc network using different wireless communication channel models

How to provide reliable, cost-effective wireless services for high-speed railway (HSR) users attracts increasing attention due to the fast deployment of HSRs worldwide. A key issue is to develop reasonably accurate and mathematically tractable models for HSR wireless communication channels. Finite-state Markov chains (FSMCs) have been extensively investigated to describe wireless channels. However, different from traditional wireless communication channels, HSR communication channels have the unique features such as very high speed, deterministic mobility pattern and frequent handoff events, which are not described by the existing FSMC models. In this paper, based on the Winner II physical layer channel model parameters, we propose a novel FSMC channel model for HSR communication systems, considering the path loss, fast fading and shadowing with high mobility. Extensive simulation results are given, which validate the accuracy of the proposed FSMC channel model. The model is not only ready for performance analysis, protocol design and optimization for HSR communication systems, but also provides an effective tool for faster HSR communication network simulation.

Comparative link-level analysis and performance estimation of channel models for IIoT (Industrial-IoT) wireless communications

Fixed-gain AF PLNC over cascaded Nakagami-m fading channels for vehicular communications

Wavelet packets (WP) have been found a promising candidate for user signature waveforms in code division multiple access communication systems. They have better orthogonality properties, and are capable of effectively suppressing certain types of noise/interferences. In this paper we present a method to model wireless communication channels using wavelet packets as bases. Modeling of wireless communication channels using WP has the advantage of more efficiency in wideband modulation. In addition, time-varying channel modeling can also be relatively easily accommodated. To evaluate the effectiveness of the proposed modeling method, we have tested it on indoor multipath fading channels. The results show promising features of the proposed model.

Wireless communication system needs a spectrum efficient, a power efficient and a cost efficient communication with high throughput to provide communication for ubiquities applications such as voice, data, picture, video, movies, multimedia services, Global Positional System (GPS), navigational system, telemedicine and other value added communication. Non-Orthogonal Frequency Division Multiplexing (NOMA) has become a popular technique for transmission of signals over wireless channels. In the first phase, MIMO system which uses NOMA is used. User signals are divided into parallel streams, using NOMA and are transmitted by the antenna array which propagates through the fading channel. signals are weighted using the Minimum Variance Distortionless Response (MVDR) where the weights are such that the output signal has minimum variance and the desired signal is not distorted. The parallel weighting scheme for interference cancellation leads to a faster, reliable and higher capacity system and results in parallel interference cancellation. Iterative process is also presented in this work, where the approximate weights are found out based on the minimum error value. Both the MVDR weighting and the approximate weighting are evaluated with the help of Bit Error Rate (BER) curves. The curves are plotted for both the Rayleigh and Rician channels. Various plots are obtained by varying the number of antennas in the array and also by varying the length of the user signal. All the BER curves achieved good results and from the analysis it is found that system performs better when Rayleigh channel was considered.

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.

A number of radio channel models based on either geometrical or statistical methods have been proposed in literature. Many such models tend to simplify the scattering environment in indoor radio medium by assuming uniform distribution of scatterers and thereby overestimate the performance of the communication system. In this paper, we present a clustering based radio channel model for a wideband frequency selective Single Input Single Output (SISO) indoor wireless channel. With the transmitter and the receiver located at the foci of an ellipse, the scatterers are modeled to be present in form of clusters of scatterers distributed randomly inside the ellipse. Further, the size and hence number of scatterers inside the cluster may vary from cluster to cluster. Such representations of the scatterers are more realistic and therefore the proposed model is expected to provide better approximation to the actual indoor environment. The proposed model has been used to evaluate the performance of a generic SISO wireless link and the results are compared with those obtained using existing channel models. The proposed channel model can be extended to a frequency selective MIMO channel simulator enabling the performance evaluation of multi-antenna wideband communication systems.

The mitigation of random effects in a wireless communication channel is a problem considered for many years. In the present day context, given the ever increasing need for, and growth of, bandwidth intensive applications like streaming wireless HD video on fast moving user equipment (UEs, i.e., user communication devices), this issue has intensified from being a theoretical pursuit to a must-be-solved practical endeavor. In that regard, the ability to accurately model the outdoor (or indoor) propagation conditions in a laboratory setting becomes vital to validating state-of-the-art wireless standards and the devices that derive from them. Laboratory-based analysis is a significant catalyst in reducing the time-to-market for telecom equipment manufacturers. Modeling a wireless channel has been a topic under quite a bit of study. This has progressed from the Jakes model developed for single antenna systems to the correlation and ray-based models used for multiple antenna systems. The models prescribed by the 3rd Generation Partnership Project (3GPP) in its standards, like the ray-based model, aim to realistically reproduce channel environments in software and hardware, by incorporating all the variables that characterize any particular fading scenario. In this thesis, the technical report produced by 3GPP detailing the Spatial Channel Modeling (SCM) for multiple input multiple output (MIMO) simulations is followed closely as a basis for developing a real-time channel emulator on a National Instruments (NI) based Real Time (RT) Platform. First, a general purpose channel emulator is described in terms of its structure and functionality and currently known channel models are briefly investigated. Next, the spatial channel model in the standard is described in detail along with the reasons for choosing to use it in the thesis. All the parameters involved are defined, and the formula for constructing the channel is carefully investigated. Next, the channel emulator built on the National Instruments LabVIEW platform is described along with both the changes and modifications made to the design parameters so as to adapt it to the operating constraints of the RT platform. The spatial and temporal characteristics of the model are also described and plotted. Finally, the model is tested for reliability by methodically changing the various channel parameters and observing their effects on an Orthogonal Frequency Division Multiplexing (OFDM) test vector by generating BER performance plots in MATLAB. Diversity schemes are also employed to improve rate performance.

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.

The wireless channel model is a deterministric or stochastic numerical description of physical propagation enviroments based on channel measurement or analysis and simulation on the basis of propagation theories. It provides an effective and simple means to approximately express the channel characteristics of the wireless transmission. Channel models can be used for link and system-level performance evaluation, optimization, and comparative studies on wireless communications technologies, algorithms, products and system. Channel model is of great importance to all wireless communications (including 5G mobile communication) research. This chapter focuses on the progress in 5G channel measurement and channel modeling. Section 3.1 introduces the requirements for 5G wireless channel model. Section 3.2 introduces and compares five commonly used channel modeling methods. Section 3.3 introduces the knowledge on channel measurement, channel measurement system and the currently ongoing 5G wireless channel measurement activities. Section 3.4 describes several channel parameter extraction algorithms and statistical analysis of channel parameters. Section 3.5 introduces several existing channel models. Section 3.6 gives an example to show the generating process of stochastic channel models. And the last section is the summary of this chapter.

Of the feedforward transmitter diversity methods considered for 3rd generation PCS/cellular systems one such method is known as phase sweeping transmitter diversity (PSTD). Since PSTD does not require a modification of the mobile station receiver, an important feature of this method is compatibility with 2nd generation as well as 3rd generation mobile stations. Furthermore, this method of transmitter diversity does not require specification in a standard. This paper provides an introduction to PSTD as it applies to IS-95 and cdma2000; the form of the received PSTD signal at the mobile station; compatibility issues between 2G and 3G; and link performance for AWGN, Rayleigh, and Ricean channel models.

This paper presents a neural network based, high power amplifier (HPA) characteristics independent adaptive method for compensation of nonlinear distortions for orthogonal frequency division multiplexing signals. Major elements that contribute to multipath fading effects are also considered and to account for major degradation categories, Rayleigh and Rician channel models are considered in an OFDM system. System performance is tested for OFDM system with and without neural block and it is proved through spectral regrowth as well as bit error rate (BER) plots that the proposed model brings in overall improvement in OFDM system.

Inter symbol interference and signal fading caused by multipath propagation are problems confronting wireless communication technology. For the UHF RFID system, multipath propagation can also reduce the system's readability and increase the bit error rate of the system. Therefore, the research of UHF RFID wireless channel is of great significance. Firstly, channel models of UHF RFID system has been analyzed in this paper. Then the maximum capacity of UHF RFID system is studied in Rician channel and Rayleigh channel with using different methods to transfer information. Water-injection method is also applied to this study. Using MATLAB simulation and two methods under the same signal to noise ratio, we found that Rician channel has a greater capacity and Rayleigh channel has a greater attenuation of the signal.

This paper discusses the performance of radio-over-fiber systems in different channels for distributing gigabit-per-second wireless signals at millimetre wave frequencies. Nonlinear distortions (NLD) in the channel reduce the dynamic range (distortion-free range for the input signal) of radio-over-fibre (ROF) links. Performance comparison of RoF in different channels shows that the dynamic range is highest in AWGN channel (highest SNR) and lesser in Rayleigh channel than Rician channel. An Orthogonal Frequency Modulated(OFDM) signal is Mach Zehnder Modulated (MZM), the generated optical signal is amplified by an Erbium Doped Fiber Amplifier (EDFA), noises are filtered, transmitted to a Radio Access Point (RAP) through a single-mode optical fiber and reached at the end user passing AWGN, Rayleigh and Rician channels.

In this paper we propose a hybrid method to determine the positions and velocities of mobile stations (MSs) in a GSM (Global System for Mobile communication) network. The proposed method can be implemented within the existing GSM standard without any additional hardware changes. The hybrid method operates at two levels. At a lower level, time delay method (TDM) is used to obtain coarse values for distances between a MS and three or more Base Transceivers (BTSs). At a higher level, field strength method (FSM) uses the coarse distances estimates obtained using TDM as initial values to obtain refined values for distances. The accurate position of a MS then can be determined by the refined distance values. Subsequently, the velocity of the MS be can obtained using the FSM estimates of the sequential positions of the MS. Least mean square (LMS) method is used to determine the refined distances in the FSM algorithm and to estimate the actual position of the MS from the refined distance estimates. The proposed method was tested for several cases, including complex MS trajectories and varying speeds along the trajectory. The heights of the BTSs were allowed to vary between 20 m and 60 m. The convergence characteristics were found to be satisfactory. For a SNR of 20 dB, position measurements accuracy in a roughly 4 km2 cell is 30 m in a Gaussian channel, 60 m in a Rayleigh channel and 80 m in a Rician channel. The velocity accuracy for a MS traveling at 200 km/h is 15 km/h in a Gaussian channel, 30 km/h in a Rayleigh channel and 50 km/h in a Rician Channel.