Mobile Relaying

Wireless cellular networks have to be designed and deployed with unavoidable constrains on the limited radio resources such as bandwidth and transmit power. The primary objective of this paper is to improve the capacity and utilization of the radio resources that are available by the service providers. This paper deals with the resource allocation problem relay-based Orthogonal Frequency Division Multiple Access (OFDMA) cellular network where relay stations (RS) perform network coding with downlink and uplink sessions of a mobile station (MS). The aim of the paper is to maximizing the weighted sum rate for both uplink and down link for all users while satisfying quality-of -services(QoS).To make the proposed system more realistic additive white Gaussian noise, and fading present in the communication channel for both uplink and down link.

Global Position System (GPS) application is quite possibly the most valuable instrument in transportation the executives nowadays. The Roadway transportation is an significant function of GPS. To track down the briefest courses to a spot is the key issue of organization investigation. To address this issue, we have numerous calculations and procedures like Dijkstra algorithm, Ant Colony Optimization, Bellman Portage Algorithm, Floyd-Warshall algorithm, Genetic Algorithm, A* Algorithm furthermore, numerous others. In this paper our fundamental goal is to assess the brute force algorithm and the dynamic programming algorithm in settling the Shortest path issue (The travelling salesman issue). The paper will be finished up by giving the results of time and space complexity of these algorithms. To help a salesman visit every one of the urban communities in the rundown (giving the area of urban areas as the information) and he knows the area of the multitude of urban communities and track down the shortest path with the end goal that he visits every one of the urban areas just a single time and gets back to the city where he begun. The distance (cost) and the relating way ought to be shown as yield. I.

In recent years, device-to-device (D2D) communication has attained significant attention in the research community. The advantages of D2D communication can be fully realized in multi-hop communication scenario. The integration of cellular and multi-hop networks not only provides guaranteed Quality of Service (QoS) and reliability as a traditional cellular network, but also has the flexibility and adaptability as a multi-hop network. Routing in such multi-hop cellular D2D networks is a critical issue, since the multi-hop network can perform worse than a traditional cellular network if wrong routing decisions are made. This is because routing in these multi-hop networks needs to take care of the node mobility, dynamic network topology, and network fragmentation, which did not exist in traditional cellular networking. This paper provides a comprehensive survey of routing in multi-hop D2D networks. Some future research directions for the routing in D2D networks are also discussed at the end of this paper.

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In the automotive and rail domains, vehicles are entering the era of full automation thanks to wireless sensors and communication systems, shifting control functions from a human driver to computers. High data rate, robustness, high reliability and ultra-low latency wireless communications are required in the context of autonomous train and safety critical applications. Today, the Future Railway Mobile Communication System (FRMCS) is under development at European level within the International Union of Railways (UIC). This system will answer all the current and future needs of rail. It will be IP based, multi-bearer and resilient to technology evolution. In the context of the development of different FRMCS prototypes by industry, it is crucial to be able to test them in representative Railway radio environments thanks to laboratory tools. Characterization of radio channels in railway environments, by measurements or simulations, is a very active field. In this article, based on broad literature survey, we show that not all the published models are suitable for performance evaluation. Then, we propose a selection of typical Tapped-Delay-Line channel models to be implemented in an original hardware and software testing platform capable to reproduce the effect of representative Railway environments in laboratory, with real time emulation at RF (Radio Frequency) level. Preliminary results in Hilly 3 taps and Cutting 5 taps channel models are presented as a proof of concept of a ''zero on site testing'' approach, allowing for time and cost savings in the validation of railway communication systems. INDEX TERMS Radio channel modelling, railway communications, tapped-delay-line models, channel emulator, open air interface, LTE.

A combination of multiple-input multiple-output (MIMO) systems and orthogonal frequency division multiplexing (OFDM) technologies can be employed in modern wireless communication systems to achieve high data rates and improved spectrum efficiency. For multiple input multiple output (MIMO) systems, this paper provides a Rayleigh fading channel estimation technique based on pilot carriers. The channel is estimated using traditional Least Square (LS) and Minimum Mean Square (MMSE) estimation techniques. The MIMO-OFDM system's performance is measured using the Bit Error Rate (BER) and Mean Square Error (MSE) levels.

Since the time, our mother earth was created, energy was taken from the universe(System),now energy is being depleted as non-renewable source. Energy can neither be created nor be destroyed as it transforms in one form to another. So researchers came up with renewable source of energy as the solution like solar, wind and tidal waves. The world is experiencing an energy crisis and the prices of petroleum products like petrol and diesel has gone up. So its time to come forward and save the future of our mother earth. The paper deals in reducing energy consumption of rail rapid transit mode i.e. of metro. It shows how driving behaviour can be controlled using optimized speed profile and efficiency can be managed. It states round trip data taken of Mumbai(India) metro from Versova to Ghatkopar and viceversa. Speed data was taken from GPS(Global Postioning System) embedded in Smart watch Software. Time interval was noted and distance, acceleration data was formulated using Newtons Equations of Motion. Energy Consumed was drawn out from tractive effort data. Then efficiency, energy lost and regenerative braking energy was calculated using Work Energy Theorem. Maximum efficiency of 88.27% was obtained between Asalpha to Jagruti Nagar Station while between Western Express Highway to Andheri Station a 72.66% efficiency was analysed. This affects the time interval of metro trains arriving at station, also the amount of boarding and alighting passengers from the train. A model was designed and simulated using results obtained. The paper also deals with the prototype of Regenerative energy which can either be used in braking systems but also for acceleration and cruising purpose. The idea can benefit a developing country like India where 6.3% GDP is from Transportation Industry.

Since the time, our mother earth was created, energy was taken from the universe(System),now energy is being depleted as non-renewable source. Energy can neither be created nor be destroyed as it transforms in one form to another. So researchers came up with renewable source of energy as the solution like solar, wind and tidal waves. The world is experiencing an energy crisis and the prices of petroleum products like petrol and diesel has gone up. So its time to come forward and save the future of our mother earth. The paper deals in reducing energy consumption of rail rapid transit mode i.e. of metro. It shows how driving behaviour can be controlled using optimized speed profile and efficiency can be managed. It states round trip data taken of Mumbai(India) metro from Versova to Ghatkopar and viceversa. Speed data was taken from GPS(Global Postioning System) embedded in Smart watch Software. Time interval was noted and distance, acceleration data was formulated using Newtons Equations of Motion. Energy Consumed was drawn out from tractive effort data. Then efficiency, energy lost and regenerative braking energy was calculated using Work Energy Theorem. Maximum efficiency of 88.27% was obtained between Asalpha to Jagruti Nagar Station while between Western Express Highway to Andheri Station a 72.66% efficiency was analysed. This affects the time interval of metro trains arriving at station, also the amount of boarding and alighting passengers from the train. A model was designed and simulated using results obtained. The paper also deals with the prototype of Regenerative energy which can either be used in braking systems but also for acceleration and cruising purpose. The idea can benefit a developing country like India where 6.3% GDP is from Transportation Industry.

A distributed collaborative uplink scheduling model in OFDMA systems is extended to a multicell scenario. On the intercell level, the scenarios with and without base station cooperation are investigated. In the cooperative case, base stations collaborate by performing pricing-based power control based on exchanging interference information. In the absence of intercell collaboration, probabilistic transmission is applied in each cell for interference avoidance. Simulations show that the proposed intercell interference mitigation and avoidance schemes lead to enhanced results.

Building approaches frequently produce schedules which induce undesired, cost-effective resource variations in the field. Two sorts of situational limitations and resource restrictions occur often with a project manager. The resources for carrying out the tasks are required for a project. These resources comprise the necessary effort, equipment and supplies. The resources in the ideal world are infinite but typically not endless throughout the real world, and the project team needs to level off resource usage.

Global Position System (GPS) application is quite possibly the most valuable instrument in transportation the executives nowadays. The Roadway transportation is an significant function of GPS. To track down the briefest courses to a spot is the key issue of organization investigation. To address this issue, we have numerous calculations and procedures like Dijkstra algorithm, Ant Colony Optimization, Bellman Portage Algorithm, Floyd-Warshall algorithm, Genetic Algorithm, A* Algorithm furthermore, numerous others. In this paper our fundamental goal is to assess the brute force algorithm and the dynamic programming algorithm in settling the Shortest path issue (The travelling salesman issue). The paper will be finished up by giving the results of time and space complexity of these algorithms. To help a salesman visit every one of the urban communities in the rundown (giving the area of urban areas as the information) and he knows the area of the multitude of urban communities and track down the shortest path with the end goal that he visits every one of the urban areas just a single time and gets back to the city where he begun. The distance (cost) and the relating way ought to be shown as yield. I.

Most of the time the spectrum is free to create more spectrums for the new user is not the best decision. There is a word in our day to day life that optimally uses the resource. So this method is used in communication line that optimally uses the spectrum so that we save money and most important thing is time. And we can use that precious time somewhere else. But the name use in communication line is Spectrum sensing. In Spectrum detecting procedure Cognitive Radio system is utilized to discover Primary client's (PUs) nonattendance in opening and helps the Secondary client (SU) for transmission. In this paper, savvy advancement of PSO with ACO is utilized. It distinguishes the Objective capacity whose worth is successfully advanced and bogus minima with PSO with ACO. Target work is finding with PSO and recognition rate is expanded and decreased bogus minima with PSO with ACO. With this, yield quickens with up to 92% and mistake rate lessens upto 10-3. PSO with ACO altogether beats and quick unite than just with PSO.

Optimal System operation involves the Consideration of economy of operation, system security, emission of certain fossil-fuel plant. The main aim of this study is to minimize the fuel cost and to keep the power outputs of the generator within prescribed limit with the use of An Ant colony Optimization Techniques. It is based on the ideas of ant foraging by pheromone communication to make path. Ant Colony Optimization technique is a meta-heuristic approach for solving hard combinatorial optimization problems which can be applied for power system optimization. The work reported in this paper is carried out with the objective to make use of Ant colony Optimization for solving the economic load dispatch problem. IEEE-26 Bus 6 generator system is considered to test the Algorithm with cost functions. The proposed approach result has been compared to those which reported in the literature.

In theory of differential equations we learn to solve (dy/dx)+Py=Q. But Its vector analogue as encountered in case of Lorentz force is extremely tedious and firstly, it was done by Gantmakher. Here a simplified version is presented for scholarly attention.

ISL played a very important role for information transmission among satellites and also for advanced information broadcasting from one satellite to another and then to ground stations. IsOWC managed the utilization of wireless optical communication with the help of lasers rather than conventional radio and microwave systems. However, there are various internal and external factors which affect the inter-satellite optical communication links. And in the conventional works, the performance of the inter-satellite optical communication links has been optimized by considering different parameters over single OWC channel link, however, it has been analyzed that in the conventional systems, the quality of the system was not much high and consequently, the inefficient systems with degraded performance and low-quality was attained. In order to address this issue, the conventional system in upgraded in this proposed work. In order to do so, the multiple-OWC channel links are implemented in the proposed work and along with that, the optical amplifier is used. The simulation of this proposed multiple-OWC-Amplifier approach is performed in terms of Q-factor by considering different data rates and different wavelengths, in order to demonstrate its efficiency. And from the obtained results, it has been analyzed that the proposed multiple-OWC-Amplifier approach outperformed conventional OWC system in terms of considered parameters.

Statistical process control is very good quality inspecting tool to improve quality of products to manufacture and scores on customer satisfaction. Process capability is one of the best statistical process control technique. This research work elaborates calculation of process capability index C p and process performance capability index C pk values for manufacturing process of drill bits. based on C p and C pk values capable and non-capable parameters are identified. For non-capable parameters cause and effect diagram is used to identify the root causes affecting to process capability. corrective actions have been taken to bring the non-capable parameter's process capability up the standard level by iterations. By using this approach, we improve C p values for point angle 0.94 to 1.47, for chip breaker angle 0.65 to 1.47, for web after notch 0.83 to 1.23 and C pk values for point angle 0.72 to 1.33, chip breaker angle 0.32 to 1.33, web after notch 0.26 to 0.75.

Software quality is a major concern for all software developers. Quality of the software can be assessed using various measures such as-the failure intensity function, the mean time to failure, failure rate etc. Several methods of estimation, like-the maximum likelihood estimation, the least square estimation etc are used in estimating these quantities. However, the software reliability, which is the probability of failure free operation of the software over a specified period of time, is an important measure of the quality of the software that helps the developers of the software to ensure that the user requirements are met. Software reliability models having certain failure time distribution are used to find the estimators of reliability and software failure data obtained during testing are used to estimate these values. Since most of the software failures have Weibull failure time distribution, herein, it is intended to estimate the reliability for the Weibull class models. The technique of Blackwellization has been used to find the minimum variance unbiased estimator of the reliability function. Few case studies have been considered to explain the behavior of this estimator.

In this era of expanding energy costs and decreasing supplies of non-renewable energy sources, it has become necessary to set up renewable energy based local power sources. This paper describes the use of piezoelectric materials in order to harvest energy from vibrations of railway track for generating and accumulating the energy. Railway locomotive and coaches produce high vibration due to heavy load during running time. The vibration is captured by using piezoelectric crystals. This idea is also applicable to some large vibration sources which can find from nature. The energy so produced is stored in a battery which is further used for other applications.

his paper presents a comprehensive analysis to examine the effectiveness of the Boothroyd Dewhurst Method for
Assembly that is used to enhance the product design process. The Design efficiency of Lamp holder B22 was calculated by
analyzing the number of necessary parts, manual handling time and manual insertion time. The product is then redesigned,
considering the manufacturing and assembly aspects and a comparative study using Boothroyd Dewhurst Method was carried
out between the original design A0 and modified design A1. Therefore, the modified design of Lamp holder was proposed to
increase the design efficiency by minimizing the number of parts and incorporating multiple parts to single part. As a result, the
design efficiency of modified design of Lamp holder has increased from 20.23% to 24.73% of around 4.5%.

Mathematical analysis for the quantification of susceptible (S(t)), Infectives (I(t)) and Removal (R(t)) populations in SIR model due to industrial pollution has been studied in the paper. The study concerns the analysis of SIR model to quantify the varying populations of S(t), I(t) and R(t) with three different sizes in the populations. A system of non-linear ordinary differential equations are solved using Runge-Kutta fourth order method to investigate the long term effect of industrial pollution on the human population in terms of spread of diseases.

Preparation of high-speed railways around the world in recent years, high-speed trains are enjoying more and more necessary role in people's travelling. Meanwhile, folks are additional needing to get wireless access services than ever before, even after they are move by high-speed trains. These along drive and raise in demand for high-speed railway broadband wireless communications and necessitate the event of a communication system for high-mobility users. A two-hop below that, under which, passengers communicate with base stations (BSs) via a mobile relay (MR) is used.The resource allocation downside in the downlink OFDMA system as a capability improvement downside for the MR subject to the total capability constraint of native users. In previous work constant power and subcarrier allocation (CPSA) polices were used. Here, the mix of the passengers and native users in order to avoid the frequency variation, OPSA system will apply for this method. Frequency would even have a significant impact on the choice of cell size. Finally, to keep up the frequency RRH are deployed in numerous areas. Thus, the stronger resource allocation within the downlink of same OFDMA system is provided. Keywords: Resource allocation, OFDMA, mobile relay, intercarrier interference, Christian Johann Doppler unfold. I. INTRODUCTION WITH the deployment of high-speed railways around the world in recent years, high-speed trains are playing an increasingly important role in people's travelling. Meanwhile, people are more eager to get wireless access services than ever before, even when they are travelling by high-speed trains. These together drive an increase in demand for high-speed railway broadband wireless communications and necessitate the development of a communication system for high-mobility users. However, current cellular systems, like 3G, LTE, or LTE-Advanced, are only powerful in providing high-data-rate wireless access services for low-mobility. When users move with a high velocity (>120 km/h), the achievable data rates of those systems drop significantly. Recently developed systems for high-speed railways can support wireless services. For instance, Thalys in Europe can provide maximum data rates 4 Mbps for the downlink and 2 Mbps for the uplink using Wi-Fi and satellite [1]. Shinkasen N700 in Japan can support data rate 2 Mbps for both downlink and uplink via leakage cable [2]. A radio-over-fiber distributed antenna system for WiMax bullet trains was developed and tested by Industrial Technology Research Institute to support data rates 3 Mbps and 2 Mbps for downlink and uplink, respectively [3]. However, the achievable rates of those systems are relatively low (2∼4 Mbps) compared to the estimated demand (37.5 Mbps) in the future [2]. Besides, these systems are dedicated and costly, and might not be suitable for widespread deployment. A more promising and economic approach is to extend the current cellular system to support high-speed railway broadband wireless communications. There are several tough problems for the application of OFDMA cellular systems in high-speed railway scenarios. First, radio signals have a significant penetration loss when passing through the alloy carriages of high-speed trains. According to [2], the penetration loss can be larger than 20 dB. Second, there will be frequent handoffs due to the high speed of trains, and a significant number of handover failures could occur with many passengers hand off simultaneously. Third, the high velocity of trains could also bring serious Doppler spread effect. For instance, the Doppler spread is 833 Hz with a carrier frequency of 3 GHz and a velocity of 300 km/h[4]. This would break the orthogonality of subcarriers of OFDM and introduce inter-carrier interference (ICI). Fourth, the environments that the train passes are various, including scenarios like viaducts, plains, urban areas, hilly areas, etc. Channel statistics in those different environments are usually different, and thus require adaptive resource allocation policies in order to optimize the transmission. Fifth, channel fading statistics of high-speed trains and local users are quite different. Therefore, resource allocation schemes should be redesigned to meet both the requirement of passengers in high-speed trains and that of local users. There are several works dedicated to determination these issues. An example, to take care of the penetration loss drawback, a two-hop design during which an access point (AP) put in within the train cabin is a mobile relay (MR) was projected in [1], [2]. During this two-hop design, passengers communicate with BSs via the MR. By putting antennas of the MR outside the train cabin; the high-penetration loss is avoided. Moreover, the design may cut back the speed of relinquishing failures since it's solely necessary to take

5G and beyond networks will offer multiple communication modes including device-to-device and multi-hop cellular (or UE-to-network relay) communications. Several studies have shown that these modes can significantly improve the Quality of Service (QoS), the spectrum and energy efficiency, and the network capacity. Recent studies have demonstrated that further gains can be achieved when integrating demand-driven opportunistic networking into Multi-Hop Cellular Networks (MCN). In opportunistic MCN connections, devices can exploit the delay tolerance of many mobile data services to search for the most efficient connections between nodes. The availability of multiple communication modes requires mode selection schemes capable to decide the optimum mode for each transmission. Mode selection schemes have been previously proposed to account for the introduction of D2D and MCN. However, existing mode selection schemes cannot integrate opportunistic MCN connections into the selection process. This paper advances the state of the art by proposing the first mode selection scheme capable to integrate opportunistic MCN communications within 5G and beyond networks. The conducted analysis demonstrates the potential of opportunistic MCN communications, and the capability of the proposed mode selection scheme to select the most adequate communication mode. INDEX TERMS 5G, mode selection, multi-hop cellular, opportunistic networking, UE-to-Network Relay, device-to-device, D2D, device-centric wireless networks.

In the present day, 5G and beyond networks are being designed to support the future increase of data traffic and service demands. To support such increase, 5G networks will incorporate device-centric technologies with adequate mechanisms to scale and handle the growing and very large number of connected devices and traffic demands. Device-centric technologies include Device-to-Device (D2D) communications and Multi-hop Cellular Networks (MCNs). In device-centric wireless networks, devices will be able to connect to the network using two different connection modes: through a traditional cellular connection, or through a multi-hop cellular connection based on D2D communications with intermediate mobile devices. Device-centric technologies will therefore provide new connectivity options and significant opportunities to enhance the capacity and efficiency of 5G networks. However, new challenges will need to be addressed. One of them is the selection of the most adequate connection mode for each mobile device, because it will be key to improve the network performance and efficiency. This work proposes a context-aware mode selection scheme capable of identifying and selecting the most adequate connection mode for each device under a wide range of deployment and operating conditions. The proposed scheme estimates the benefits and risks of each connection mode based on context information available at the base station guaranteeing low signaling overhead. The obtained results show that the proposed mode selection scheme helps achieving throughput gains higher than 200% compared to traditional single-hop cellular communications for devices at the cell edge, and significant gains are also achieved compared to other mode selection schemes implemented and evaluated.

Multi-hop Cellular Networks using Mobile Relays (MCN-MRs) are being investigated to help address certain limitations of traditional single-hop cellular communications. A key element of MCN-MR technologies is the mode selection scheme that selects the most adequate connection mode (traditional single hop cellular or multi-hop link) for each transmission. This paper proposes a novel mode selection scheme that uses context information to select the connection mode, and can adapt its decisions to the operating conditions. This study shows that the proposed scheme outperforms distance-based mode selection schemes, and helps improving the MCN-MR performance with respect to single-hop cellular communications.

Cellular operators are facing considerable capacity and energy-efficiency challenges as cellular data traffic keeps on rising. Several studies have shown that multi-hop cellular networks (MCN) could help tackle these challenges through the integration of device to device and cellular communications. This study demonstrates that significant energy-efficiency gains can be achieved when MCN networks jointly exploit opportunistic networking and the traffic delay tolerance characteristic of relevant mobile data services.

Multi-hop Cellular Networks using Mobile Relays (MCN-MRs) are being investigated to help address certain limitations of traditional single-hop cellular communications. The MCN-MR benefits depend on the probability to find adequate mobile relays, and on the design of mode selection schemes capable to identify the optimum connection mode. The probability to find adequate mobile relays can be significantly enhanced for delay tolerant services through the adoption of mobile opportunistic networking that exploits the store, carry and forward paradigm. In this context, this paper proposes and evaluates the first mode selection scheme that integrates opportunistic networking into MCN-MR. The obtained results demonstrate that the proposed scheme helps achieve the expected QoS and energy benefits that opportunistic networking can bring to multi-hop cellular networks.

Traditional single-hop cellular architectures fail to provide high and homogeneous quality of service levels throughout a cell area due to the strong signal attenuation
with the distance. In this context, multi-hop cellular networks that utilize mobile relays and device-to-device communications have been proposed to overcome the physical limitations of conventional cellular architectures. One of the key building blocks of multi-hop cellular networks is the multi-hop routing of information from the source to the destination. This paper investigates the performance and energy
signaling benefits of location-based multi-hop routing protocols. In particular, the paper demonstrates the benefits of a contextual optimization of this type of protocols in order to achieve a high end-to-end performance, while reducing the energy and signaling implementation cost.

5G networks will be required to efficiently support the growth in mobile data traffic. One approach to do so is by exploiting Device-to-Device (D2D) communications and Multi-Hop Cellular Networks (MCNs) in order to enhance the spectrum re-use and offload traffic over underlay networks. This study proposes to further improve the efficiency of transmitting mobile data traffic by integrating opportunistic networking principles into MCNs. Opportunistic networking can exploit the delay tolerance characteristic of relevant data traffic services in order to search for the most efficient transmission conditions in MCNs. The study first presents an analytical framework for two-hop opportunistic MCNs designed to identify their optimum configuration in terms of energy efficiency. Using this reference configuration, the paper then proposes a set of opportunistic forwarding policies that exploit context information provided by the cellular network. Numerical and simulation results demonstrate that opportunistic networking can significantly contribute towards achieving the capacity and energy efficiency gains sought for 5G networks. Under the evaluated conditions, the obtained results show that the proposed schemes can reduce the energy consumption compared to traditional cellular communications by up to 98% for delay tolerant services. In addition, the proposed schemes can increase the cellular capacity by up to 79% compared to traditional cellular communications.

Radio resource allocation plays a vital role in case of multi-users, multi-relay orthogonal frequency division multiple access (OFDMA) based systems. Let us consider an OFDMA based wireless relay networks where multiple user pairs exchange information via multiple relays using full duplex communications. The optimization problems like channel allocation, power allocation and relay selection can be formulated as a mixed integer programming problem. Proposed efficient optimal resource allocation algorithm is formed to minimize total transmit source power per subcarrier and number of relays with required data rates. Simulation results prove that the proposed optimal [5] method can improve OFDMA based multi user relay networks significantly with required data rates.