Communication Coverage Research Articles

Traffic Optimized Content Precaching Scheme Based on Tolerable Delay Time in Content-Centric Vehicular Networks

The development of smart vehicles such as self-driving cars has resulted in an increased demand for content consumption in vehicles. This demand for content, coupled with the improved quality of the content and the expanding resolution of the display, leads to a significant increase in mobile data traffics with larger sizes in content-centric vehicular networks (CCVNs). Since a single RSU cannot fully provide the larger size contents in its communication coverage due to its limited transmission rate, many studies on precaching contents have been actively conducted. By considering only delay-sensitive contents, previous precaching schemes immediately precache contents in the next continuous RSUs on trajectories of vehicles through paying lots of traffics for reducing delays. However, every application content in CCVNs might generally have a tolerable delay time to vehicles according to its characteristics related to service satisfaction. By considering the tolerable delay time, the already stored content on RSUs reached by vehicles within the tolerable delay time can be exploited to download the content without precaching. As a result, precaching of contents can be reduced and thus the traffics can be also reduced. To address this issue, we thus propose a Traffic Optimized Content Precaching (TOCP) scheme based on the tolerable delay time in CCVNs, which minimizes traffics consumed for delay-tolerant contents and decreases delays for delay-sensitive contents. To do this, we first provide a numerical model to judge the precaching necessity by calculating the content provision possibility. Next, we build a Delay-tolerant content Management Module (DMM) for managing the updated information and design new packet formats for reducing the movements of the large-size contents to achieve the optimization purpose of TOCP. Then, we select Optimal Precaching RSUs (OPRs) by solving our optimization problem by using ILP. Last, we provide a process for allowing only OPRs to participate in the content provision. Through simulation results conducted in various environments, we demonstrate that TOCP minimizes the traffic and caching burden while maintaining high reliability in comparison with the previous schemes.

The representation of animal communication and language evolution in introductory linguistics textbooks

AbstractThe last three decades have brought a wealth of new empirical data and methods that have transformed investigations of language evolution into a fast-growing field of scientific research. In this paper, we investigate how the results of this research are represented in the content of the most popular introductory linguistic textbooks. We carried out a comprehensive computer-assisted qualitative study, in which we inspected eighteen English-language textbooks for all content related to the evolutionary emergence of language and its uniqueness in nature, in order to evaluate its thematic scope, selection of topics, theories covered, researchers cited, structural soundness, currency, and factual accuracy. Overall, we found that the content of interest lacks a defined canonical representation across the textbooks. The coverage of animal communication was relatively broad, with some recurring classic examples, such as vervet monkeys or honeybees; this content was mostly structured around the ‘design features’ approach. In contrast, the coverage of topics related to language origins and evolution was much less extensive and systematic, and tended to include a relatively large the proportion of content of historical value (i.e. creation myths, ‘bow-wow’ theories). We conclude by making recommendations for future editions of textbooks, in particular, a better representation of important frameworks such as signalling theory, and of current research results in this fast-paced field.

PARTISIPASI ELEMEN MASYARAKAT FILM TERHADAP PERSOALAN LINGKUNGAN HIDUP

Environmental issues are very complex things that require the participation of various elements of society. The film community is one element of society that is expected to contribute to participation in environmental management. The film produced by the community is one of the cultural artifacts, environmental communication is also inseparable from culture as its context. Film is also a participatory media that is used for the important role of community participation in creating special appropriate media content. With a qualitative descriptive method, this study aims to determine the strategy of the film community in conveying environmental messages. The results showed that the two selected communities had an equally important concern for environmental sustainability. Both use social media for communication coverage through films by choosing advocating narratives to provide a space for dialogue between the general public and interested parties, in this case the government and contributors to environmental problems.

Genetic Algorithm Based BER Aware Channel Selection Using Break Point Technique For Next Generation Milli-Meter (mm) Wave Communication Systems

Due to exponential increase in communication speed when shifting from 4th Generation 4G to 5G networks, there is a requirement to redesign equipment to support spectrum ranges from 450 MHz to 52.6 GHz, which makes them operate at very high speeds. In order to maintain good communication performance while operating at this bandwidth, millimeter waves (mmWaves) are used. As communication radius increases, the BER also increases linearly, which limits range of these equipment’s, thereby incurring higher deployment costs. In order to reduce these costs, and design mmWave communication components to work for larger areas, this text proposes a Genetic optimization architecture that uses intelligent channel modelling and selection. The architecture is designed in order to reduce BER during communication when threshold breakpoint occurs, thereby improving communication speed, and overall throughput. It exploits long-ranged loopback communications in order to automatically tune internal transmission parameters for supporting larger areas with minimum packet loss. The underlying model is tested on various channel types, different network scenarios, and under different noise conditions. It is observed that the proposed model outperforms original mmWave communication models in terms of BER reduction by 8% and in terms of communication coverage by 6%, thereby making it applicable for wider geographical areas. This results in reduced deployment costs, and better communication quality of service (QoS), thereby assisting in better network design.

Spectrum Sharing in the Sky and Space: A Survey

In order to achieve the vision of seamless wireless communication coverage, a space-air-ground integrated network is proposed as a key component of the sixth-generation (6G) mobile communication system. However, the spectrum used by aerial networks has become gradually crowded with the increase in wireless devices. Space networks are also in dire need of developing new bands to address spectrum shortages. As an effective way to solve the spectrum shortage problem, spectrum sharing between aerial/space networks and ground networks has been extensively studied. This article summarizes state-of-the-art studies on spectrum sharing between aerial/space networks and ground networks. First, this article provides an overview of aerial networks and space networks and introduces the main application scenarios of aerial networks and space networks. Then, this article summarizes the spectrum sharing techniques between aerial/space networks and ground networks, including existing spectrum utilization rules, spectrum sharing modes and key technologies. Finally, we summarize the challenges of spectrum sharing between aerial/space networks and ground networks. This article provides guidance for spectrum allocation and spectrum sharing of space-air-ground integrated networks.

Optically Transparent Antennas: A Review of the State-of-the-Art, Innovative Solutions and Future Trends

The requirement of mounting several access points and base stations is increasing tremendously due to recent advancements and the need for high-data-rate communication services of 5G and 6G wireless communication systems. In the near future, the enormous number of these access points might cause a mess. In such cases, an optically transparent antenna (OTA) is the best option for making the environment more appealing and pleasant. OTAs provide the possible solution as these maintain the device aesthetics to achieve transparency as well as fulfill the basic coverage and bandwidth requirements. Various attempts have been made to design OTAs to provide coverage for wireless communication, particularly for the dead zones. These antennas can be installed on building windows, car windscreens, towers, trees, and smart windows, which enables network access for vehicles and people passing by those locations. Several transparent materials and techniques are used for transparent antenna design. Thin-film and mesh-grid techniques are very popular to transform metallic parts of the antenna into a transparent material. In this article, a comprehensive review of both the techniques used for the design of OTAs is presented. The performance comparison of OTAs on the basis of bandwidth, gain, transparency, transmittance, and efficiency is also presented. An OTA is the best choice in these situations to improve the aesthetics and comfort of the surroundings with high antenna performance.

Adaptive blind receiving for deep VLC coverage innon-uniform LED systems.

Recently, visible light communication (VLC) has become a promising technology for reliable communication in the industrial Internet of Things. In VLC, light sources with non-uniform parameters make uncontrollable signal blind zones and aliases. The unknown parameters also lead to the problem of channel estimation. Hence, deep coverage of VLC is challenging. In this paper, we design a dual-sensor elongated receiver. The receiver expands the signal receiving area by increasing the distance between photon detectors and realizes aliased signal recovery without channel estimation. Cooperatively, an adaptive blind receiving scheme is proposed. The scheme separates aliased signals by parameter estimation of a Gaussian mixture model without knowing transmitter parameters. It unifies the aliased and blind receiving cases by an adaptive signal combining method. Finally, the simulation results demonstrate that our scheme achieves better reliability and deeper communication coverage in the given system.

Vehicle-cluster-based opportunistic relays for data collection in intelligent transportation systems

Intelligent transportation system (ITS) is envisioned to greatly improve traffic and enhance safety on roads. ITS relies on a huge amount of data generated from roadside sensor devices to make decisions. Due to the limited channel resources, the base station (BS) that connects with an ITS server can only collect data from parts of sensor devices at a time. To improve the number of device associations, we regard vehicle clusters as relays to collect data, which can avoid high capital expenditure and operating expenses from dedicated relays. Due to the frequently varying channel interference and the limited communication coverage of a vehicle cluster relay (VCR), it is challenging to guarantee the transmission rates and the fairness of sensor devices, which will affect the decisions of ITS. For this reason, we propose a Movement- and Fairness-Aware Heuristic (MFAH) algorithm to tackle the above challenges. MFAH sequentially conducts two novel channel allocation schemes, i.e., exclusive channel allocation scheme and compatible channel allocation scheme, to fast allocate channels and improve the channel utilization, which increases the number of device associations while guaranteeing the transmission rates. Regarding the fairness of each device’s associations, we propose a device association scheme based on the cumulative number of device associations and the distance from the target VCR to select appropriate sensor devices to upload data. We theoretically analyze the lower bound of the obtained network utility. Extensive simulations show that compared with benchmarks, the proposed MFAH algorithm converges fast and effectively improves the network utility (i.e., increasing the number of device associations while guaranteeing the fairness of device associations).

SECURITY OF AUTONOMOUS VEHICLES: 5G IOV (INTERNET OF VEHICLES) ENVIRONMENT

Abstract. An autonomous vehicle is designed to move partially or totally without the intervention of the driver. It is a system equipped with sensors, communication and processing units that make it able to monitor and analyse traffic information in real time to improve road safety. In addition, Internet of Vehicles is the latest technology dedicated to autonomous vehicles, the integration of this technology with 5G serves as a platform to interconnect sensors, vehicles, infrastructure, pedestrian, and network. Hence, the 5G Internet of Vehicles environment provides significant benefits, including increased security, high reliability, wide communication coverage and low service latency. On the other hand, due to the ubiquity of network connectivity, it also presents serious confidentiality, integrity, and availability issues for autonomous vehicles. This paper provides an overview of the autonomous vehicle concept by highlighting its technologies and the 5G IoV environment, presenting some susceptible attacks that can touch the security of this environment, and some good practices to ensure the autonomous vehicle security.

Reinforcement Learning Assisted Bandwidth Aware Virtual Network Resource Allocation

Space-air-ground integration to support seamless coverage of ground, satellite, airborne, and marine communications, is likely to be a key trend in the 6G era. One of several key challenges in such space-air-ground integration networks (SAGINs) is to design efficient scheduling approaches for multi-dimension network resources. Due to the inherent heterogeneity characteristics, we demonstrate how can transform the network resource allocation problem in SAGINs into a multi-domain virtual network resource allocation problem, as well as proposing a reinforcement learning assisted bandwidth aware virtual network resource allocation algorithm (RL-BA-VNA). Specifically, RL-BA-VNA leverages reinforcement learning and uses a policy network as an agent to perform the node embedding. In order to support users’ exacting bandwidth requirements, we prefer to select virtual network requests with large bandwidth for embedding. Experiment findings show that the proposed algorithm RL-BA-VNA outperforms respectively the other three conventional virtual network resource allocation algorithms RL, DRL and BASELINE by an average of 2.06%, 4.93%, 11.07% in terms of long-term average reward, acceptance rate, and long term reward/cost.

Problems and prospects of digitalization of agriculture in the Republic of Tyva

The problems and prospects of development of digital technologies in the agricultural sector of the Tyva Republic were studied. The use of digital technology remains extremely low in Tyva. The region significantly lags behind Russia as a whole and the Siberian Federal District in the development of digitalization processes. Challenges hindering the development of the information society in the Republic of Tyva are the presence of hard-to-reach settlements with complex geographical features; infrastructure restrictions in terms of registration (approval) of necessary documents and interaction with network organizations in the conclusion of contracts for technological connection to the power grid; lack of coverage and uncertain reception of mobile radio telephone communications in remote rural settlements of the Tyva Republic; lack of qualified specialists in information and telecommunication technologies, poor development of scientific and innovation potential; low skills in using information technologies; import dependence on imported software, technologies and equipment; digital inequality between municipalities. To improve the efficiency of agriculture in the region, it is necessary to introduce digital technologies into agricultural production: collecting data on sown areas and pastures, making digital maps of agricultural land, using remote-controlled sensors to monitor the quality of crops, the movement of agricultural vehicles and animals, etc. The use of digital technologies will promote the products of agricultural producers to the consumer, which will expand access to financial resources and markets due to the coordinated action of all parts of agricultural production. The main directions of digitalization of the industry were outlined and promising digital technologies for application in the agricultural sector of the Tyva Republic were specified.

Investigation of Radio Frequency Signal Propagation of Wireless Services in Oyo, Oyo State, South Western Nigeria

This study reported the investigation of the Radio Frequency (RF) signal propagation of Global System for Mobile Communications (GSM) coverage in Emmanuel Alayande College of Education (EACOED), Oyo, Oyo State, Nigeria. The study aims at amplifying the quality of service and augment end users' sensitivity of the wireless services operation. The drive test method is adopted with estimation of coverage level and received signal strength. The Network Cell Info Lite application installed in three INFINIX GSM mobile phones was employed to take the measurement of the signal strength received from the transmitting stations of different mobile networks. The results of the study revealed that MTN has the maximum signal strength with a mean value of - 68.33 dBm, directly followed by Globacom (-80.41 dBm) and Airtel with -83.13 dBm. The Airtel signal has a conspicuously invariable poor performance with coverage level of 41.66 %. Conversely, the MTN and Globacom signal reception are observed to surpass the Airtel network within the college premises with 83.33 % and 60.41 % coverage level respectively. This implies that the signal quality for MTN and Globacom networks were comparatively disseminated within the college with inconsequential fluctuations in quality while Airtel signal is subsided and weaken. The poor performance in some areas was due to the presence of physical impediments and far distances location of base station antennas in the promulgation locations. This study therefore suggested that Airtel and Globacom Base Transceiver Stations (BTS) should be positioned within the college to improve good network reportage level.

Joint Transmit Power and Trajectory Optimization for Two-Way Multihop UAV Relaying Networks

Unmanned aerial vehicle (UAV) has been more and more widely used in military and civilian, with its unique advantages of flexibility, convenience, and wide coverage. As flying stations, UAVs can quickly set up relay communication links for different missions, to enhance the receiving signal power, increase the system capacity, and expand the communication coverage. In this article, we investigate a two-way multihop UAV relaying network, where there are two ground users as sources and multiple UAVs as relays to help the two ground sources exchange information. For the purpose of enhancing the efficiency of the investigated UAV-assisted relaying, we come up with a productive two-way multihop UAV relaying pattern, which can achieve a data rate of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$({1}/{2})$ </tex-math></inline-formula> data packets per time slot with the decode-and-forward protocol. Then, we further formulate a joint transmit power and trajectory optimization problem for the UAVs in this two-way multihop relaying scenario. The formulated problem is nonconvex which makes it difficult to solve directly; hence, we propose an iterative algorithm to obtain an approximate optimal solution based on block coordinate descent and successive convex optimization techniques. Numerical results demonstrate that our proposed two-way multihop UAV relaying network achieves significant throughput gains compared with other benchmark schemes.

Unmanned Surface Vessel Assisted Maritime Wireless Communication Toward 6G: Opportunities and Challenges

Sixth generation (6G) mobile communication aims to construct an autonomous network architecture with human-like consciousness and intelligence. 6G mobile technology is expected to integrate space, air, ground, and sea networks to provide full-dimensional wireless and ubiquitous coverage. Compared to terrestrial communications, maritime wireless communications are still far behind expectations to satisfy 6G requirements for ubiquitous wireless connectivity and extensive coverage. Fortunately, the unmanned surface vessel (USV) with agile maneuverability and adaptive capability is a potential solution to enhance maritime communication coverage and performance. However, how to apply mobile USVs to maritime wireless communication is still an open issue. In this article, we provide an overview of USV-assisted maritime wireless communication by introducing three typical USV application scenarios, basic networking architecture, andvdesign considerations, as well as the main challenges. An example of USV-assisted mobile relaying is conducted to demonstrate the benefits provided by adopting USV in maritime wireless communication.

Communication-Constrained Routing and Traffic Control: A Framework for Infrastructure-Assisted Autonomous Vehicles

With the increasing demand for advanced autonomous driving, the available communication resources may become constrained over different geographic areas. In addition, due to dynamic channel variations and imperfect cell deployments, guaranteeing the required communication resources for data hungry and delay-sensitive applications in autonomous vehicles (AVs), along their entire trips, becomes challenging. To address these issues, the paper investigates the feasibility of a hybrid system-optimum and user-equilibrium AV traffic framework subject to communication constraints, as well as its performance gain. Within such a framework, the paper introduces the problems of communication-constrained routing (CCR) and traffic control (CCTC) in the context of infrastructure-assisted autonomous driving and presents respective solutions. For CCR, an efficient two-layered routing scheme is proposed which can provide optimal trip duration. Simulation results show that the routing scheme achieves a good balance between longer duration of communication coverage and acceptable source-to-destination travel time. For CCTC, it is shown that there exists an optimal AV speed on each road segment, as well as an optimal inter-AV distance and an optimal number of AVs in each cell, to maximize the road-network AV throughput within a single cell. Moreover, spectrum allocation is used to achieve Pareto-optimal road-network throughput across cells, and a new key performance index (KPI) is defined to evaluate the traffic control capability of cellular systems. Simulation results validate the improvement of AV throughput via the proposed CCTC solution.

“We Write to Dismantle Prejudices, Myths and Lies”: The Role of Journalists in the COVID-19 Vaccination Campaign in Romania

ABSTRACT In Romania, an important role in the dissemination of scientific information, decisive for increasing confidence in the vaccination against COVID-19, was played not only by official communication,, but also by media professionals who covered this subject extensively. The present research analyses the opinions of 33 Romanian journalists, from the national and local press, aiming to find out their professional attitude regarding the vaccination campaign. The opinions were collected through the structured interview, applied through electronic communication channels, between February 20, 2021 and March 1, 2021. Several research questions were the basis of this article: how professional journalists understand the role of the press in a pandemic crisis, in which disinformation, fake news, and deceptive information, decreased trust in vaccination; how journalists relate to the state of balance and what they consider to be the role of the journalistic act, also in relation to the authorities. The most important result of this study is that many of the interviewed journalists believe that, in the context of the national and global health crisis, the correct information is based on scientific evidence and the coverage of official communication, with the role of professional journalism being to combat misinformation, pseudoscience, conspiracies, and fake news.

Deployment of UAV-BSs for on-demand full communication coverage

Unmanned Aerial Vehicle (UAV) mounted Base Stations (UAV-BSs) have been widely used to enhance communication coverage for ground user devices (UDs) due to their intrinsic nature of flying. In this paper, we study the deployment of UAV-BSs for on-demand full communication coverage problem. Firstly, we give the scenario model together with communication model and coverage model. Secondly, we formulate full communication coverage problem considering network robustness and QoS provided. Thirdly, to address this problem, we propose two UAV deployment algorithms to minimize the number of UAVs while achieving on-demand full coverage. Particularly, these two UAV deployment algorithms only differ in building/updating service connections. Finally, simulation results demonstrate the efficiency of our proposed algorithms.

Enhanced Artificial Gorilla Troops Optimizer Based Clustering Protocol for UAV-Assisted Intelligent Vehicular Network

The increasing demands of several emergent services brought new communication problems to vehicular networks (VNs). It is predicted that the transmission system assimilated with unmanned aerial vehicles (UAVs) fulfills the requirement of next-generation vehicular network. Because of its higher flexible mobility, the UAV-aided vehicular network brings transformative and far-reaching benefits with extremely high data rates; considerably improved security and reliability; massive and hyper-fast wireless access; much greener, smarter, and longer 3D communications coverage. The clustering technique in UAV-aided VN is a difficult process because of the limited energy of UAVs, higher mobility, unstable links, and dynamic topology. Therefore, this study introduced an Enhanced Artificial Gorilla Troops Optimizer–based Clustering Protocol for a UAV-Assisted Intelligent Vehicular Network (EAGTOC-UIVN). The goal of the EAGTOC-UIVN technique lies in the clustering of the nodes in UAV-based VN to achieve maximum lifetime and energy efficiency. In the presented EAGTOC-UIVN technique, the EAGTO algorithm was primarily designed by the use of the circle chaotic mapping technique. Moreover, the EAGTOC-UIVN technique computes a fitness function with the inclusion of multiple parameters. To depict the improved performance of the EAGTOC-UIVN technique, a widespread simulation analysis was performed. The comparison study demonstrated the enhancements of the EAGTOC-UIVN technique over other recent approaches.

A Three-Phase CDRT Strategy Based on Successive Relay for Smart Grid

In the vision of the future smart grid, the communication is often featured by wide range, massive connect, and low latency, which poses new requirements on the reachable distance and spectral efficiency of wireless communication. In this regard, this paper studies ergodic capacity enhancement by applying successive relay (SR) technology to a non-orthogonal multiple access (NOMA) based Coordinated Direct and Relay transmission (CDRT) system, where a base station (BS) communicates with a near user (NU) directly while communicating with a far user (FU) with the help of a group of relays. We design a novel three-phase CDRT strategy based on SR technology to overcome the half-duplex (HD) constrain without introducing additional noise. The proposed strategy can improve the spectral efficiency while expanding the communication coverage, which to some extent improves the communication quality of the edge users of the smart grid and reduces the communication delay. To analyze the performance of the proposed three-phase CDRT strategy, an exact and closed-form expression for ergodic capacity of the NU, the FU, and the whole system is derived. Finally, the numerical and simulation results validate the analysis results and show that the proposed strategy can improve the ergodic capacity of FU without reducing the capacity scaling of NU.

Terrain-aware communication coverage prediction for cooperative networked robots in unstructured environments

Networked robots will play an important role in lunar exploration. Communication is key to enable cooperation among robots for information sharing, and to remotely control robots with lower degree of autonomy from a lander or habitat. Operators and scientists must be able to make sound decisions on communication availability before or during sending robots to regions of interest for exploration. In this work we have a closer look at the communication coverage prediction for lunar exploration. We present an interdisciplinary and modular framework, which exploits terrain information to predict the data rate for exploring robots. Additionally, we create intuitively usable coverage maps for operators and scientists, and show how connectivity can be improved in unstructured environments by using a relay rover. This paper provides an overview of this framework, details on individual framework components, and simulation results for two exemplary exploration scenarios.