Communication Operations Research Articles

Distributed computing in special purpose wireless telecommunication systems: performance and prospects

The study is devoted to the analysis of the application of distributed computing technologies in wireless telecommunication systems. The paper considers the concept of cloud radio access networks (C-RAN) and their use to improve productivity and reduce costs of communication operators. The logical relationship of mobile devices, cloud wireless network and internal servers is considered, as well as the role of split-TCP-proxy in the distribution of connections and maintenance of constant communication between the user and the internal server of the cloud. It is noted that the dynamic operations of the wireless network cloud, such as topology configuration and data rate distribution, provide better service at the upper layer. The importance of knowing the state of the wireless channel for the successful implementation of operations in C-RAN is emphasized. It is noted that the use of distributed computing in wireless systems can reduce deployment and maintenance costs, providing efficient data transmission and improved performance. The obtained results indicate the possibility of successful use of distributed computing technologies in wireless telecommunication systems. This opens prospects for communication operators to reduce costs and improve the quality of service. The research is relevant in the context of the continuous development of wireless technologies and has the potential for further research and improvement of wireless telecommunication systems. Future work may focus on expanding the scope of research, including a wider range of technologies and algorithms that can be used to optimize the performance of cloud radio access networks. In addition, the impact of using distributed computing technologies on other aspects of wireless systems, such as security, resource management, and scalability, can be considered. Research may also focus on the use of other protocols and algorithms to distribute computing tasks and optimize data transmission.

Method for detecting the source of radio interference affecting train radio communication in the band of 2.13 and 2.15 MHz

There are many factors that infl uence the process of organising train movements, quality radio communication being one of the most important. The intelligibility of the dispatcher’s commands to the driver is important in deciding what action to take, and in informing the dispatcher of the train situation on a particular section of the track. Sources of radio interference that have an interfering effect on the quality of the train radio signal are natural and artifi cial interference. The sources are mainly low-frequency interference. One of the constant sources of high-frequency emissions that affect stable operation of train radio communications refers to discharges generated in the high-voltage insulation of power lines, including discharges generated in the insulation of overhead wires. Spark discharges, the source of radio interference, occur both on the surface of the insulator (usually called surface partial discharges (SPD)) and inside the insulation (such discharges are called partial discharges (PD)). In the operation of high voltage insulation, those insulators that contain PD and PPD are called defective insulators. PD and PD diagnostics are carried out twice a year by means of a laboratory car. Discharge registration is performed in the visible and ultraviolet range. There are acoustic methods for registering PD and SPD. It is proposed to register discharges in the electromagnetic frequency range. For prompt detection radio interference, it is recommended to place antennas on the laboratory car, and combine measurements with current diagnostics of high-voltage insulation, that will allow increasing reliability of the results received in the course of diagnostics. To increase the accuracy of radio interference source detection, two antennas are considered to be placed on the laboratory car.

Low-complexity frequency-domain nonlinear equalizer with absolute operation for underwater wireless optical communications.

A low-complexity 3rd-order frequency-domain nonlinear equalizer (FD-NLE) with absolute operation is proposed and experimentally demonstrated for underwater wireless optical communications (UWOC). In the proposed FD-NLE scheme, absolute operation and fast Fourier transform (FFT) with multiplication operations are utilized instead of the square and convolution operations used in conventional polynomial nonlinear equalizers (PNLEs), respectively. Therefore, complexity reductions by over 77.3% and 66.9% can be achieved compared with those of PNLE and PNLE with absolute operation, respectively, with a memory length larger than 8. A UWOC system using orthogonal frequency division multiplexing (OFDM) signals with adaptive bit and power loading is also demonstrated to evaluate the performance of the proposed scheme. Experimental results show that data rate increments by ∼ 5.6% and ∼ 5.7% at BER below 7% hard-decision forward error correction (HD-FEC) limit of 3.8 × 10-3, compared with PNLE and PNLE with absolute operation, respectively, are realized using the proposed scheme. Meanwhile, the proposed scheme has an up to 14.7% complexity reduction compared with conventional frequency-domain PNLE (FD-PNLE), while maintaining similar equalization performance.

Nonlinear mathematical modeling in the model of village cultural industry

Abstract To solve the problem that the current forecasting methods cannot describe the long-term correlation of traffic, which leads to low prediction accuracy, the author proposes a mathematical modeling, forecasting and analysis method for village nonlinear traffic. The original nonlinear traffic data collected from the village comes from each base station, the information contained is uneven, pre-processing the collected data, eliminating abnormal values and duplicate data, and supplementing the missing data. Nonlinear traffic contains limited information, so a random forest algorithm is used to extract traffic characteristics and reduce data processing dimensions. The nonlinear traffic characteristics of the village are convolved, and the cross entropy function is used as the loss function, the feature vector of the input prediction model is deeply learned, and the communication traffic prediction results are obtained. Taking the traffic data of the communication operation enterprise’s base station as the test data, the experiment results show that, in the test with 1 million pieces of data, the decision coefficient of the mathematical modeling, prediction and analysis method of village nonlinear flow designed by the author is 0.9599, which is 0.1267 and 0.1431 higher than the prediction and analysis method based on genetic algorithm and fuzzy clustering algorithm respectively. In the modeling and prediction of nonlinear flow, the determination coefficient of the method proposed by the author is closer to 1, the fitting degree of this method is better than that of the contrast method, and it is adaptive in the real scene with a large amount of data. It is proved that the mathematical modeling and prediction analysis method designed in this design can reduce NRMSE and MAPE, improve the determination coefficient of prediction results, and provide the basis for village analysis.

Data Management in IoT: A Detailed Survey

This paper surveys the current state of data management in the Internet of Things (IoT). It begins by outlining the challenges and opportunities that data management in IoT presents. Firstly, data management deals with the technical challenges and solutions related to data management in IoT, including data acquisition, storage, and integration. The paper concludes with a set of recommendations for the development of effective data management strategies in the context of IoT. Secondly, the requirement of IoT for data management extends offline storage, query processing, and transaction management activities into online-offline communication and storage dual operations, and the idea of data management is broadened. This is accomplished by IPv6, as well as IoT-specific capabilities and protocols including CoAP, HTTP, and WebSocket. Users may track, monitor, and manage devices with Internet of Things (IoT) device management, ensuring that they operate effectively and securely after deployment. Finally, the paper discusses the various applications of IoT based on the concept of data management in IoT. Numerous more objects, including wearables, medical equipment, houses, cities, farms, industries, and workplaces, are being interacted with by billions of sensors. The IoT platforms assist in establishing and maintaining criteria to enhance and preserve data appropriately. The paper concludes with a set of recommendations for the development of effective data management strategies in the context of IoT. Smart gadgets automate processes so we may save time by controlling the environment. The most valuable data is protected by edge devices for data management, which also lowers bandwidth costs. These also offer excellent performance, data ownership, and cheap maintenance costs.

Tkachenko Methodology for building radio relay lines based on the use of geospatial information

When planning and organizing communication using modern military digital radios, a crucial and relevant task is to ensure the maximum possible communication range while providing the necessary speed and quality of information transmission. The main factors determining the possible communication range of modern military digital radios, in addition to their characteristics, are the terrain relief, buildings, and vegetation. Additionally, existing height objects in the area, such as communication operator towers, can be used to organize radio relay communication. An analysis showed that existing methods and specialized software can be used for certain calculations of signal levels, but they do not always take into account all necessary technical parameters of radio equipment and additional geospatial information. Moreover, the existing software is not designed to construct multi-interval radio relay lines while considering additional geospatial data. In constructing radio relay lines, there is often a situation where one interval cannot provide communication with the required quality. This situation calls for planning a radio relay line using relay stations. The choice of the location of relay stations depends on many factors, including the possibility of establishing communication, minimizing the number of relays, geospatial information regarding the terrain relief, and the presence of the necessary infrastructure (buildings, power supply, anchor points, towers, etc.) in the area. The article proposes a methodology for constructing radio relay communication lines based on calculations of signal levels while considering geospatial data. This methodology allows analyzing individual radio relay intervals for constructing multi-interval radio relay lines. The software implementation of the developed methodology allows creating software for calculating radio relay lines with the necessary input data and geospatial information regarding the terrain.

Integrated Operation and Maintenance of Power System Communication Based on the Markov Model

Abstract Based on the Markov model, a fault warning system for power grid operation is proposed. Its main objective is to improve the execution effect of alarm commands. Firstly, the power grid operation reliability evaluation model based on the Markov model is established. According to the set critical value to judge the change of power grid operation state. Develop abnormal alarm commands for power grid operation. Strange events are described in detail using natural language technology, and corresponding instructions are completed in the system. After the comparative test, the new alarm improved more remarkably than the traditional intelligent alarm mode.

Technology Diffusion System Model of China's Communication Industry

This paper hopes to describe the technology diffusion of 5G in China's communication industry at a point in time almost two years after the commercialization, and to explore and verify the factors affecting its diffusion. Based on the data published by the Ministry of Industry and Information Technology of China, the model is established by using STELLA as a tool. Simulations are conducted by profiling the system from both the Chinese government and communication operators' perspectives to predict the change in the number of 5G adopters over time. The results show that two factors, namely the Chinese government increasing the construction of communication infrastructure, and the operators increasing the types of 5G technology services, have a more significant effect on increasing the rate of 5G user adoption in China during the early stage of 5G technology into the individual consumer market.

Ultraviolet random access collaborative networking protocol based on time division multiple access

The ultraviolet network, with its advantages of high security, non-line-of-sight communication, and all-weather operation, has broad military application potential. This study proposes an ultraviolet random access collaborative networking protocol based on time division multiple access that combines the benefits of synchronous and asynchronous media access control protocols. Considering the physical layer characteristics, the frame structure of the protocol is constructed based on a cross-layer design. Compared with the time division multiple access protocol, the proposed protocol can achieve higher throughput with a lower delay and packet loss rate by the dynamic timeslot allocation mechanism. Then, the effects of maximum cache capacity and burst traffic on network performance are investigated. Finally, the conducted network experiments prove the cooperative forwarding and random access capabilities of the ultraviolet random access collaborative networking protocol. The proposed protocol provides a reliable and effective method for independent and flexible ultraviolet networks.

Inside Back Cover

The picture shows an artificial DNA reaction network to mimic the operation and function of synaptic communication via strand‐displacement reaction. DNA is used as simple artificial analogs to schematize structures and transmit information. The proposed network enables core functions of synaptic communication, such as the long‐term potential. More details are discussed in the article by Wu et al. on page 1313–1318.image

Quantum Genetic Algorithm for the Design of Miniaturized and Reconfigurable IoT Antennas

This paper leverages an automated quantum genetic algorithm (QGA) to design miniaturized antennas for Internet of Things (IoT) devices. The QGA implemented in this work automates the design process and enables the antenna designer to generate static or reconfigurable miniaturized microstrip folded antenna topologies. The QGA is also implemented to generate a pixelation pattern within the antenna radiating surface to optimally tune the antenna operation for IoT communication needs as well as for Wi-Fi operation. In this paper, we also present a QGA-optimized folded miniaturized antenna in both static and reconfigurable topologies. The reconfiguration is achieved through a single RF MEMS whose location is optimized through the automated process. The automated design process achieves 87% antenna size reduction at 868 MHz compared to a typical patch antenna operating at the same frequency. As a result, the static and reconfigurable antenna prototypes achieve good radiation efficiencies in comparison to their miniature size with acceptable gains thus satisfying the IoT physical and operational constraints. Both antennas are fabricated and tested, where excellent agreement is noticed between simulated and measured results.

A Joint Radar and Communication Approach for 5G NR using Reinforcement Learning

Radar operation partly overlaps and thus interferes with 5G spectrum bands. Examples are vehicular radar, long-range air traffic control, terminal air traffic control, marine radar, airport surveillance, or also operations in the mmWave band. We propose a mechanism to efficiently share the spectrum resources for communication and radar operation using a Reinforcement Learning (RL)-based approach. Unlike the state-of-the-art, our approach enables both systems to keep their own waveforms. Compared to the use of a single waveform for joint radar and communication, this results in less complex signal processing and improved sensing resolution. Our approach is compatible with existing radar systems and requires software modification only for the communication system. We demonstrate how both systems can work simultaneously, thereby eliminating the need for time sharing. The effectiveness of the approach is studied through a comprehensive set of experiments implemented in an open source simulation environment. It is shown that in the presence of interference, the radars can still achieve a high accuracy for range and velocity estimation of targets. The system achieves high spectrum utilization and is on-demand adjustable to realize any desired level of trade-off between communication and sensing.

Dichromatic "Breather Molecules" in a Mode-Locked Fiber Laser.

Bound states of solitons ("molecules") occur in various settings, playing an important role in the operation of fiber lasers, optical emulation, encoding, and communications. Soliton interactions are generally related to breathing dynamics in nonlinear dissipative systems, and maintain potential applications in spectroscopy. In the present work, dichromatic breather molecules (DBMs) are created in a synchronized mode-locked fiber laser. Real-time delay-shifting interference spectra are measured to display the temporal evolution of the DBMs, that cannot be observed by means of the usual real-time spectroscopy. As a result, robust out-of-phase vibrations are found as a typical intrinsic mode of DBMs. The same bound states are produced numerically in the framework of a model combining equations for the population inversion in the mode-locked laser and cross-phase-modulation-coupled complex Ginzburg-Landau equations for amplitudes of the optical fields in the fiber segments of the laser cavity. The results demonstrate that the Q-switching instability induces the onset of breathing oscillations. The findings offer new possibilities for the design of various regimes of the operation of ultrafast lasers.

Design of Dual Band Microstrip Patch Antenna for 5G Communication Operating at 28 GHz and 46 GHz

Design of Dual Band Microstrip Patch Antenna for 5G Communication Operating at 28 GHz and 46 GHz

DESIGN AND ANALYSIS OF MULTI-BAND COMPACT MICROSTRIP ANTENNA IN GSM1900/WLAN/WiMAX/DSRC/X-BAND FREQUENCY BANDS FOR VEHICLE APPLICATIONS

This study focuses the design and analysis of a compact, multi-band microstrip patch antenna for wireless communications operations. The design antenna exhibits distinct quad resonance frequency bands I from 1.879 GHz to 1.986 GHz, II from 3.1 GHz to 3.87 GHz, and III from 4.97 GHz to 6.515 GHz, IV from 7.26 GHz to 8.6 GHz, which covers GSM 1.900 GHz, WLAN (5.2/5.8 GHz), DSRC 5.9 GHz and WiMAX (3.5/5.5 GHz) bands. In addition, it can also support the X-band from 7.26 to 8.6 GHz. The antenna is designed on an inexpensive substrate of FR4 with dimensions of 36(L) × 25(W) mm2 and consists of two branches of curved strips for a quad-band response. The antenna is designed and analyzed using electromagnetic 3D computer simulation software. The designed antenna can provide advantages in GSM/WLAN/WiMAX/DSRC/X-band satellite applications for vehicle communication with four resonant frequency bands, nearly omnidirectional radiation characteristics, and acceptable gain.

Prior Pharmacy Work Experience as a Predictor of Clinical and Didactic Performance for Admissions Committees

ObjectiveTo investigate prior pharmacy work experience (PPWE) in admissions to predict clinical and didactic performance. MethodsIn this retrospective study, data from 3 cohorts, classes of 2020–2022, were collected. Multivariate regressions were conducted to determine the impact of PPWE on performance in first-year pharmacy (P1) Community Introductory Pharmacy Practice Experience (IPPEs), second-year pharmacy (P2) institutional IPPEs, P2 & third-year pharmacy (P3) Observed Structured Clinical Examinations (OSCEs), Drug Information class and P1, P2, P3 grade point averages (GPAs). ResultsOf 329 students, those who had PPWE (n = 210) worked as pharmacy technicians (78%), clerks, cashiers, drivers (10%), or other (12%). The majority worked in community settings (86%) and worked an average of 24 h weekly. PPWE was not associated with any pharmacy school GPAs. Those with PPWE scored 2.17 out of 100% points higher in Drug Information than those who did not. They also scored higher on P1 IPPE performance in communication and pharmacy operations skills; however, these notable differences did not continue in P2 IPPEs or OSCEs. Total hours worked in higher quartiles were also associated with increased scores in P1 IPPE communications skills, P1 IPPE pharmacy operations skills, and Drug Information course scores. ConclusionPrior pharmacy work experience modestly improved pharmacy school performance in selected areas in the P1 year, but the effect did not continue in later years. Students who had PPWE performed better in Drug Information and P1 IPPE communication and pharmacy operations skills.

Fast UAV path planning in urban environments based on three-step experience buffer sampling DDPG

The path planning of Unmanned Aerial Vehicle (UAV) is a critical issue in emergency communication and rescue operations, especially in adversarial urban environments. Due to the continuity of the flying space, complex building obstacles, and the aircraft's high dynamics, traditional algorithms cannot find the optimal collision-free flying path between the UAV station and the destination. Accordingly, in this paper, we study the fast UAV path planning problem in a 3D urban environment from a source point to a target point and propose a Three-Step Experience Buffer Deep Deterministic Policy Gradient (TSEB-DDPG) algorithm. We first build the 3D model of a complex urban environment with buildings and project the 3D building surface into many 2D geometric shapes. After transformation, we propose the Hierarchical Learning Particle Swarm Optimization (HL-PSO) to obtain the empirical path. Then, to ensure the accuracy of the obtained paths, the empirical path, the collision information and fast transition information are stored in the three experience buffers of the TSEB-DDPG algorithm as dynamic guidance information. The sampling ratio of each buffer is dynamically adapted to the training stages. Moreover, we designed a reward mechanism to improve the convergence speed of the DDPG algorithm for UAV path planning. The proposed TSEB-DDPG algorithm has also been compared to three widely used competitors experimentally, and the results show that the TSEB-DDPG algorithm can archive the fastest convergence speed and the highest accuracy. We also conduct experiments in real scenarios and compare the real path planning obtained by the HL-PSO algorithm, DDPG algorithm, and TSEB-DDPG algorithm. The results show that the TSEB-DDPG algorithm can archive almost the best in terms of accuracy, the average time of actual path planning, and the success rate.

Some Attitudes of Professionals Towards the Agility of Their Educational Institution

Agility as a special way of thinking and acting was created by programmers and has spread to the pedagogical field. We are presenting the results of a survey among 184 professionals from various Slovenian educational institutions (EI) for the purpose of determining their attitudes towards the agility of EI. The results show that respondents agree the most with positive actions, positive emotions and care for children. They are most indecisive about simplifying issues and problems and highlighting mistakes. Based on multivariate hierarchic cluster analysis, we determined three clusters that, according to our research, define agile EI. We named them as follows: the individual and the operation of EI, positive mindset and adequate communication. All clusters relate to human resources and confirm the statement that the greatest challenge is to achieve change in people.

The Medium Is the Environment: Digital materialism, climate crisis and digital art as pedagogy

This article examines the environmental implications of ubiquitous information and communication technologies (ICT) manufacturing, operations and usage, using the theories of new materialism and digital materialism, and offers an interactive video installation as a case study for contemporary digital art’s pedagogical potential in response to such environmental issues. Contrary to the imageries of the cloud and the notion of immateriality as promoted by the tech industry, digital media systems are grounded in the material world and operate at the expense of the material substrate. Such a sociopolitical landscape warrants an exploration of potential counter tactics in the fields of digital art and art education. Being informed by digital materialism and hinged on the notion that encounters with contemporary art can cultivate critical and different ways of knowing, this article proposes that a focus on the material can function as an antithesis to the abstracting act of information/data and its purported immateriality.

Electromagnetic Band Gap Based Via-less Jeans Patch Antenna for 5.5GHz WiMAX Application

Wearable electronics have gained opportunities in recent years, and the last decade has been evidence of this growth in Wireless Body Area Networks (WBAN). They meet the criteria for personalizing healthcare, communication, patient monitoring, tracking, and rescue operations. The main challenge for the WBAN is to handle the radiator's coupling with the human body. An artificially generated Electromagnetic Band Gap (EBG) structure was designed and used in this work to improve the performance of a microstrip patch antenna. A jeans-based microstrip patch antenna with an EBG surface demonstrated to enhance the performance for 5.5 GHz WiMAX application. The use of an EBG surface increases return loss by 20%, with a reasonable bandwidth of 0.528 GHz (5.271 GHz to 5.749 GHz) at the resonance frequency of 5.5 GHz. The EBG surface improved the Voltage Standing Wave Ratio (VSWR) by 60%. A three-layered human body tissue model is also used for on-body measurements to determine the performance of an EBG-based antenna. The presence of human tissues generally reduces performance and shifts the resonance, but the shifting in this work with the simplified EBG structure and adequate gain and VSWR is only 2.6 percent.