Network Coverage Area Research Articles

MARKOV MODEL OF WIRELESS SENSOR NETWORK AVAILABILITY

The use of wireless sensor networks (WSN) in industry and for forest fire detection has recently become increasingly popular. Assessment of the availability of such networks is an important task, since they perform essential functions in critical situations. Sensor networks can be used to prevent and detect forest fires, and they must meet high availability requirements. Various options for organizing the WSN system are considered - with and without recovery. For such systems, the paper evaluates the probability of no-failure operation, as well as the readiness function, taking into account the network coverage ratio. In the paper the Markov WSN model for evaluating its availability function is developed taking into account the network coverage area. The obtained graphical dependencies allow us to evaluate how a change in the failure rate of sensors or system equipment affects the availability function value. The goal of this paper is to obtain metrics to assess the availability of system for monitoring forest by WSN and the availability function of a network using the Markov models. A special metric, so-called coverage availability factor is suggested in this paper taking into account different combinations of sensor failures which influence on completeness of monitoring forest fires.

TV Advertising - Factors of Influence

Except the audience performances of the television channels and the known advantages of this communication mean, the transmission of the advertisement spots thought television is done in a different manner, also depending on the reception method, the number of the TV channels from a television network and depending on the coverage area of the respective television network. Thus we distinguish: the advertisement realized by the network television, the advertisement realized through the local television and the advertisement realized by cable television. The choice of one of these methods by the announcers is made depending of the advantages or/and the limits that each of these are present it.

Mitigation of receiver biases in ionospheric observables from PPP with ambiguity resolution

PPP (Precise Point Positioning) is a GNSS (Global Navigation Satellite Systems) positioning method that requires SSR (State Space Representation) corrections in order to provide solutions with an accuracy of centimetric level. The so-called RT-PPP (Real-time PPP) is possible thanks to real-time precise SSR products, for orbits and clocks, provided by IGS (International GNSS Service) and its associate analysis centers such as CNES (Centre National d'Etudes Spatiales). CNES SSR products also enable RT-PPP with integer ambiguity resolution. In GNSS related literature, PPP with ambiguity resolution (PPP-AR) in real-time is often referred as PPP-RTK (PPP – Real Time Kinematic). PPP-WIZARD (PPP - With Integer and Zero-difference Ambiguity Resolution Demonstrator) is a software that is made available by CNES. This software is capable of performing PPP-RTK. It estimates slant ionospheric delays and other GNSS positioning parameters. Since ionospheric effects are spatially correlated by GNSS data from active networks, it is possible to model and provide ionospheric delays for any position in the network coverage area. The prior knowledge ionospheric delays can reduce positioning convergence for PPP-RTK users. Real-time ionospheric models could benefit from highly precise ionospheric delays estimated in PPP-AR. In this study, we demonstrate that ionospheric delays obtained throughout PPP-AR estimation are actu ally ionospheric observables. Ionospheric observables are biased by an order of few meters caused by the receiver hardware biases. These biases prohibit the use of PPP-WIZARD ionospheric delays to produce ionospheric models. Receiver biases correction is essential to provide ionospheric delays while using PPP-AR based ionospheric observables. In this contribution, a method was implemented to estimate and mitigate receiver hardware biases influence on slant ionospheric observables from PPP-AR. In order to assess the proposed approach, PPP-AR data from 12 GNSS stations were processed over a two-month period (March and April 2018). A comparison between IGS ionospheric products and PPP-AR based ionospheric observables corrected for receiver biases, resulted in a mean of differences of −39 cm and 51 cm standard deviation. The results are consistent with the accuracy of the IGS ionospheric products, 2–8 TECU, considering that 1 TECU is ~16 cm in L1. In another analysis, a comparison of ionospheric delays from 5 pairs of short baselines GNSS stations found an agreement of 0.001 m in mean differences with 22 cm standard deviation after receiver biases were corrected. Therefore, the proposed solution is promising and could produce high quality (1–2 TECU) slant ionospheric delays. This product can be used in a large variety of modeling approaches, since ionospheric delays after correction are unbiased. These results indicate that the proposed strategy is promising, and could benefit applications that require accuracy of 1–2 TECU (~16–32 cm in L1).

An Energy Optimization Clustering Scheme for Multi-Hop Underwater Acoustic Cooperative Sensor Networks

In this paper, we propose an improved energy optimization clustering algorithm (EOCA) for the multi-hop underwater acoustic cooperative sensor networks (UWA-CSN) due to the limited energy supply of the underwater sensor nodes. The proposed EOCA scheme considers multiple factors, such as the number of neighbor nodes, the residual energy of each node, the motion of the sensor nodes caused by the ocean currents, and the distance between the sink node and each underwater sensor node. All these factors are considered within the framework of the multi-hop cooperative communication. Moreover, in the proposed energy optimization scheme, we define a residual energy based maximum effective communication range (reE-MECR) according to the residual energy of each underwater sensor node, which can adaptively control the energy consumption of data transmission for each hop. Compared with the existing clustering scheme, the experimental results demonstrate that the proposed EOCA scheme can not only prolong the life time of the multi-hop UWA-CSN, but also keep a good communication and networking performance, including the package delivery ratio, the energy consumption efficiency, and the network coverage area. The proposed scheme can obtain both the clustering benefit and the cooperative communication benefit for the multi-hop UWA-SN in terms of energy saving in underwater environments.

Dynamic Resource Allocation for Scalable Video Streaming in OFDMA Wireless Networks

Mobile video streaming is a successful example of Cyber-Physical-Social Systems (CPSS). How to schedule network resources and provide better mobile video streaming services for mobile users are very important. Scalable video streaming is regarded as a promising technology in wireless networks where the cognitive femtocells are overlaid within the coverage area of a macrocell network. In this paper, we study dynamic resource allocation for scalable video streaming over cache-enabled wireless networks with time-varying channel conditions. We formulate the scalable video streaming problem as a stochastic optimization problem which aims at maximizing the time-averaged system utility subject to the time-averaged video cache constraint at the server and the cross-tier interference constraint on the primary user under the sparse deployment scenario of femtocells. By employing the Lyapunov optimization theory, we design a dynamic cache and resource allocation (DCRA) algorithm to solve this problem. Furthermore, the problem is decomposed into three subproblems, i.e., video layer selection, cache placement, and wireless resource allocation. Via solving these subproblems, we derive the video layer selection and cache placement strategies, and a wireless resource allocation algorithm to manage the cross-tier interference. Simulation results demonstrate the advantages of the proposed DCRA for streaming scalable video over time-varying wireless networks.

Multipath Routing and MPTCP-Based Data Delivery Over Manets

In some special circumstances (e.g., tsunamis, battlefields, and earthquakes), communication infrastructures are damaged or nonexistent. For communication among people, mobile smart devices (MSDs) can be used to construct mobile ad hoc networks (MANETs). This paper focuses on the problem of data delivery in MANETs aiming to improve the quality of service (QoS) and quality of experience (QoE) users receive. MANETs, however, have the well-known problems of frequent disconnections and high rates of failed transmissions as MSDs move in and out of network coverage areas, and the topology constantly changes. To solve these issues, the main contributions of this work are as follows: (1) we provide and investigate the QoE-driven multipath TCP (MPTCP)-based data delivery model in MANETs; (2) we present hidden Markov model-based optimal-start multipath routing, which can effectively predict a mobile node's near future network connection state according to its past connection state; (3) we leverage MPTCP to simultaneously transmit data via multiple interfaces of MSDs and improve the establishment method for MPTCP subpaths; and (4) we study and improve the algorithm of multihop routing in MANETs. The test results show that our algorithms can offer more efficient use of multiple subpaths and better network traffic load balancing than using standard MPTCP alone.

SECURED CAR HELPLINE NAVIGATION SYSTEM “CC HELPLINE”

There are several studies that have been implemented in the relation to navigation management system, most of which are research has done on the Secured Car Helpline navigation system. These studies have a mutual agreement with the motor insurance provider and service center provider that is highly dependent to ensure a good collaboration of business. One of the limitations that are gain from the proposed system is a collaboration between all the motor insurance agencies to gather the sufficient information to apply during the incident. In order to overcome the issue, the respective management members need to conduct a talk or speech with the respective representative of all motor insurance provider and service provider collaborate to make Secured Car Helpline navigation system “CC Helpline” more convenient. Hence, there is a certain location that has poor signals on the user’s device, where the respective user is unable to surf for a better connectivity in low network coverage areas. Not all the area has good strength connectivity, dead zones area considered due to limited access or no cellular connectivity. One of the ways of approaching this situation that is to get the better view of the issue, collaborating with Asia’s telecommunication such as Digi, Maxis, Celcom and U-Mobile to expand the network connectivity into unreachable areas and every user’s designated destination. As a proposed system, it has to develop as a live car helpline navigation system requires a good connectivity to the browser internet connection and a good network strength.

A review of mobility management entity in LTE networks: Power consumption and signaling overhead

SummaryMobility management (MM) in Long‐Term Evolution (LTE) networks is a vital process to keep an individual User Equipment (UE) connected while moving within the network coverage area. MM Entity (MME) is the LTE component responsible for tracking and paging procedures and controlling the corresponding signaling between the UE and its serving cell, which is necessary for data‐packet exchange. Because of the massive increase in the density of mobile UEs, MME is burdened by the high volume signaling load, especially because most of that load comes from Tracking Area Update (TAU) and Paging messages, which are essential to exchange UE‐specific information with the network. To achieve cost‐efficient resource provisioning, many solutions have been proposed for TAU and Paging management to optimize not only UE experience (ie, battery power consumption) but also network resources (ie, bandwidth). In this paper, we discuss various solution schemes for TAU and Paging in terms of complexity, latency, and computation costs. Also, this review discusses the adverse effects of these solutions on the LTE Key Performance Indicators (KPIs). Furthermore, we present a new trend of MM solutions in LTE networks, called software‐defined network (SDN) and software‐defined virtualization (SDNV). To this end, we examine the existing schemes and challenges in the literature toward next‐generation wireless networks (eg, 5G, Internet‐of‐Things [IoT], and machine to machine [M2M] communications), and we describe user mobility models that are used to analyze the network performance.

Design of coverage algorithm for mobile sensor networks based on virtual molecular force

General virtual force algorithm, when the density of sensor nodes is large in the monitoring area, there are some shortcomings, such as uneven distribution of nodes, more overlap of coverage area and so on. In view of these shortcomings, based on the basic idea of air molecular theory, a virtual molecular force model of mobile sensor networks is established, and the virtual molecular force algorithm for node deployment and mobile coverage of mobile sensor networks is given. The virtual molecular force algorithm assumes that there is interaction between nodes in mobile sensor networks, and the resultant force of these forces constitutes the resultant force network of sensor nodes in the monitoring area, which drives the sensor nodes to move to the corresponding location to repair the monitoring blind area, so as to maximize the coverage of the network. In order to verify the feasibility and effectiveness of the virtual molecular force algorithm, the virtual molecular force algorithm for mobile sensor network node deployment and mobile coverage is simulated and analysed by using MATLAB simulation tool. The simulation results show that the virtual molecular force algorithm can make the sensor nodes repair the monitoring blind area efficiently and quickly, and maximize the monitoring coverage area of the sensor network. In terms of repairing monitoring blind areas and improving network coverage, the virtual molecular force algorithm is superior to other network coverage algorithms such as general virtual force algorithm.

Generalized Coordinated Multipoint (GCoMP)-Enabled NOMA: Outage, Capacity, and Power Allocation

A novel generalized coordinated multi-point transmission (GCoMP)-enabled non-orthogonal multiple access (NOMA) scheme is proposed. In particular, distributed base stations (BSs) in a network coverage area cooperate on the downlink to serve a set of user equipments (UEs) using the same transmission frequency band. Furthermore, all UEs associated to a BS and using a particular frequency band forms a single NOMA cluster. The number of BSs serving a UE in a particular frequency band is referred to as the order of clustering (or order of BS cooperation). To evaluate the proposed scheme, we derive a closed-form expression for the probability of outage for a UE with different orders of BS cooperation. To obtain important insights on the performance of the proposed system, approximate (asymptotic) expressions for the probability of outage and outage capacity are derived considering both perfect and imperfect channel state information (CSI) estimation. We observe that improved spectral efficiency with a large number of UEs per NOMA cluster can be achieved by increasing the clustering order (i.e., number of cooperating BSs per UE). Furthermore, an optimal transmission power allocation scheme that jointly allocates transmission power fractions from all cooperating BSs to all connected UEs is developed.

Heterogeneous network optimization using robust power-and-resource based algorithm

<p>In order to meet the increasing mobile data-traffic, spatial densification of network with several low-power nodes, the high-power macro BS and HetNet are the major key enabling solution. However, the HetNet is unplanned in nature, causes irregularities and interferences that without any user association rules. The appropriate deployment of the femto-cell in HetNet can provide effective traffic offloading, where the alleviate mobbing in the macro-cells can decrease the power consumption therefore it optimizes the user experience. Moreover, the protection is also important for the macro and femto cell users in a network through maintaining the min-max level of interferences. In this paper, we proposed RPRA that comprises two robust approach such as robust power-controller and the robust channel-allocation approach, which can improve the spectral efficiency and user experiences at lower network coverage areas via eliminating the week coverage zones. Also provide high user rate connection by effective interference in an efficient spectrum, lowering in transmission power and cost-effectiveness via less time delay. To show the effectiveness of our proposed model we have compared with several existing techniques and we got significant improvement in throughput, also reduction in time delay and transmission power.</p>

АНАЛИЗ МЕТОДОВ СБОРА И МАТЕМАТИЧЕСКОЙ ОБРАБОТКИ РАЗНОРОДНОЙ ИНФОРМАЦИИ ПО ОЦЕНКЕ СОСТОЯНИЯ ЗОНЫ ОБСЛУЖИВАНИЯ СЕТЕЙ ОПЕРАТОРА СВЯЗИ

The article analyzes the methods and means of collecting, identifying and processing information related to technical, social and economic parameters of network coverage area. One of the trends in the telecommunications market is a continuous increase in the volume of transmitted traffic while maintaining indicators such as the average revenue per subscriber and the total number of subscribers for telecom operators. Taking into account the analysis of development trends in order to preserve the profitability of work, telecom operators need to increase the efficiency of their work by reducing the cost of maintaining the infrastructure and promoting new services. To solve these problems, it is necessary to use various types of information gathering about the state of the network coverage of a provider. The analysis of methods for collecting information on the network coverage revealed three main types. The first relates to the methods of collecting technical parameters of communication channels between the base stations of the operator and subscriber equipment. The second consists in collecting information on subscriber complaints about the service quality by means of the customer interaction service. The third is conducting marketing research to predict the needs of subscribers for new services. The results of the analysis show that the greatest difficulties in collecting and processing information are related to the complex identification of the network coverage area, taking into account technical and socio-economic factors. The difficulties have been caused by the limitations of the available technical means for analyzing the state of the network coverage area to an integrated generalization of heterogeneous information. According to the analysis results of theoretical methods, it has been stated that using the methods of the theory of fuzzy sets is most appropriate for generalizing the information presented in numerical and verbal form.

Real-Time Wireless Control for a Data Acquisition-Based Micro-Computer System

Real-time communications (RTC) wireless multi-channel data acquisition systems provide promising remote interactive solutions. This paper develops and implements wireless octet channels for data detection and processing. Data analysis and suitable control action are accomplished by using an Arduino UNO controller interfaced with the National Instruments (NI) LabVIEW virtual engineering toolset. A simple graphical user interface has been developed and implemented. Sensors for humidity, pulse, temperature and motion are used for reading the environmental parameters. The system can accommodate measurements of eight individual parameters at different reading speeds. In addition, high-accuracy data measurements can be obtained by using the mean values technique for the three sensors in cases such as temperature and humidity. An efficient storage technique for dated and timed data can be optimized to cancel all successive repeated measurements. Whenever the environmental parameters have been changed the system will store only the updated changes, thus providing an accurate enough description of the sensor output as well as significant reduction in required memory. Quad flags are implemented as the actuators triggering signals. The acquired data can be remotely monitored via either smartphones or computers located in the WI-FI local area network coverage area.

Spectral Efficiency Improvement based on Small-cell Deployments Toward 5G Communications Technologies

This paper emphasizes a method for improving spectral efficiency based on small cells (SCs) deployed in an existing macrocell (MC), which ultimately results in overall enhancement of the network capacity and coverage area. In addition, it allows an unlicensed secondary network to deliver messages through opportunistic access to the licensed network spectrum. By deploying SCs, users either inside or outside high residential buildings and/or commercial buildings can acquire signals during communications without interruption. The connectivity in the alliance of the two-tier networks becomes abundant, resulting in spectral efficiency improvement. In this paper, we first recall performance based on the Vandermonde-subspace frequency division multiplexing (VFDM) spectrum-sharing technique for spectrum management under both conventional (single-user) and enhanced scenarios; subsequently, the proposed method is introduced for comparison purposes. The performance of both methods is manifested in simulation results for the achievable rate, which demonstrate that the proposed approach outperforms enhanced VFDM and is a potential candidate in next-generation cellular technology. The motivation for the preference for SC deployment in the proposed approach is due to worthy characteristics (low power, low cost, very light weight, and self-organization). Unlike MCs, which need a considerable budget, they are installed anywhere without a lot of expense, and hence, save the network infrastructure.

Secure and efficient data delivery for fog-assisted wireless body area networks

The growth of remote patient monitoring technology introduces new opportunities for improving patient outcomes, and Wireless Body Area Networks (WBANs) are a key piece in building a successful system. However, due to the limited power and computational resources of WBAN sensor nodes, combined with user mobility and large network coverage areas, integrating WBANs with cloud and fog computing presents one of the most viable options for successful remote monitoring. In order to help maintain the real-time operations of a fog-assisted WBAN, we propose a secure and efficient data delivery protocol that will reduce delay and protect against malicious attacks on the wireless signal. The protocol is composed of three custom algorithms that address channel assignment, gateway association, and introduce a new delay- and energy-aware routing metric. The channel assignment algorithm is designed to minimize and avoid interference, including jamming nodes. The fog gateway association algorithm helps to improve the efficiency and security of the connection between the WBAN and the remote resources. Similarly, the proposed routing metric is used to construct routes that both minimize delay and conserve power at the nodes along the path for improved efficiency and lifespan of the network. The system was simulated and tested under a variety of conditions to evaluate its performance in regards to mutual interference, human mobility, fog density, and attacks by jamming nodes. The results showed clear improvements in the efficiency and resiliency of the fog-assisted WBAN system when utilizing our protocol.

Performance Impact of Relay Selection in WiMAX IEEE 802.16j Multi-hop Relay Networks

Worldwide Interoperability for Microwave Access network accepts the challenge of last mile wireless access for internet. IEEE 802.16 standard, commercially known as WiMAX provide wireless broadband experience to the end subscribers and challenges many wired solutions like Digital Subscriber Line (DSL) and cable internet. Wireless network has many inherent issues like coverage holes; capacity optimization and mobility are few of them. Adding relays to multi-hop WiMAX IEEE 802.16j network present an effective solution to address them to some extent but this amendment does not elaborate any algorithm regarding the relay selection and narrate no performance guarantees. In this work, we proposed linear model that fairly allocates wireless resources among subscribers in 802.16j network. A relay selection algorithm is also presented to optimally select nodes with higher signal-to-noise ratio as relay station for nodes with lower signal-to-noise ratio objectively maximize overall network capacity. This scheme further extends network coverage area and improves network availability. We also did extensive performance evaluation of the proposed linear model. Results show that optimal relays selection scheme do provide a substantial increase of up to 66% in overall network capacity in the fixed WiMAX network. This improvement is substantial at places where network condition is not optimal. Investigating the problem further leads to the conclusion that the relay selection criterion is the key to achieve maximum network capacity.

PRELIMINARY ANALYSIS OF WIRELESS COLLABORATIVE NETWORK ON MOBILE DEVICES

Researchers and companies of telecommunication sector have been working hard to enhance wireless network infrastructure to fulfill the end user’s needs for Internet connectivity. However, it is not easy to satisfy the high demand and expectation of end users always. There are some situations where Internet connectivity is not enabled due to the locations and environmental constraint. For example, network infrastructure breakdown during a disaster or the user’s device is out of the network coverage area. Besides relying only on the network infrastructure provided by telecommunication companies, one possible strategy to provide Internet connectivity in the ubiquitous environment is to exploit the functionality of end-user mobile devices to be the tool to share Internet connectivity. This paper aims to identify the constraints and challenges of forming Wireless Collaborative Network (WCN) by the end user devices. To identify the constraints and challenges, we have reviewed and categorized the past and current research focusing on collaborating mobile devices in the mobile ad-hoc network for communication and resource sharing. For validation, a simple test case was conducted which involves few mobile devices in a random formation. Base on the finding, it is concluded that the biggest challenge of forming WCN is the ability of mobile devices to provide bridging functionality. This paper also discussed the expecting architecture of WCN and suggested the simulation tools with relevant metrics to be considered in this research area.

Studies on the Directivity of Horn Antennas for Communication Links in Low Network Coverage Areas

Studies on the Directivity of Horn Antennas for Communication Links in Low Network Coverage Areas

Green resource allocation method for intelligent medical treatment‐oriented service in a 5G mobile network

SummaryDue to the development of mobile transmission techniques, more exciting services can be launched that may change our daily lives in more easy and comfortable ways. The introduction of device‐to‐device (D2D) service in future 5G communication systems can extend the service coverage of intelligent medical treatment from hospitals to anywhere inside the network coverage area, which can save precious time and medical resources. As one of the key techniques in a 5G system, D2D technology has attracted extensive attention from academia and industry due to its system performance improvement, user experience enhancement and service extension. However, the introduction of D2D service will tremendously pollute the system transmission environment due to the induced interference, especially in the downlink direction where the interferer is very strong. This situation brings new challenges for effective and green resource utilization. To solve this problem, a green spectrum resource allocation strategy based on the Hungarian method is proposed in this paper to optimize system spectrum efficiency while considering the fairness among users under the assumption that all resources are fully shared by traditional cellular and newly introduced D2D users. To validate the performance of the proposed algorithm, a system‐level Monte Carlo simulation is also conducted, which shows the favorable performance of the proposed algorithm over the traditional greedy algorithm.

QoE-Driven Optimized Load Balancing Design for Hybrid LiFi and WiFi Networks

The hybrid light fidelity (LiFi) and wireless fidelity (WiFi) networks are regarded as a promising solution for future indoor wireless communication. In this letter, we investigate the traffic load balancing (LB) issue for this hybrid networks. In our design, considering that user terminals (UTs) may have different data rate demands, we utilize the complementary advantages of the wide bandwidth of the LiFi network and the wide coverage area of the WiFi network to serve the UTs. With considerations of the access point heterogeneity and UTs’ quality of experience (QoE) demands for data rate, we then formulate the LB issue as a mixed-integer non-linear programming problem with the aim of maximizing the system throughput under proportional fairness constraints, and propose a distributed optimal algorithm and a simplified suboptimal sequential algorithm to solve it. Simulation results demonstrate that using the presented QoE-driving LB scheme, more UTs are served with higher QoE while maintaining high system throughput and proportional fairness.