Mobile Communication Equipment Research Articles

The Systematic Construction of Emergency Medical Security System in Long-Distance Walking Movement on Urban Paved Roads

Objective To explore the scope of building emergency medical security mechanism in urban paved road environment, and to provide reference, sample data and improvement suggestions for building emergency medical security mechanism in such specific environment. Methods The data of rescue personnel deployment, rescue materials allocation, rescue force monitoring, actual rescue situation, emergency plan and relevant regulations setting, training and other aspects of the emergency medical security mechanism in March and April 2023 were collected, and the data were analyzed. Results (1) The hiking distance was 40km and the road conditions were urban paved roads. There were 1150 official trekkers and 65 people were treated medically. (2) The most common symptoms of outdoor hiking included skeletal muscle injury (19.48%), foot skin and soft tissue injury (18.17%), fever (2.61%) and diarrhea (0.61%). (3) In March, 18.36% of the core medical team members and 20.41% of the first aid volunteers who underwent systematic training took up the task of supporting hiking activities. In April, the core medical team personnel who undertook the task of supporting hiking activities accounted for 1.23% of the total number of the security team, and the first aid volunteers who underwent systematic training accounted for 37.04%. (4) According to local conditions, the multi-vehicle rescue and transport mode was adopted, which was combined with the modified commercial rescue vehicle (42.86%) with the on-board emergency medical unit (EMU) and the ordinary ambulance (28.57%). (5) More than 700 pieces of 34 kinds of medical materials and 40 sets of mobile communication equipment, which were put into use after the feasibility study of the expert group and the technical group, guaranteed the competition from the hardware level. Conclusion The construction of emergency medical support mechanism in outdoor walking sports needs to pay attention to environmental characteristics, operation mode of support team, personnel and adaptability training, equipment and deployment of medical support materials, deployment and cooperation of communication and transport capacity, reasonable support plan and other factors. Medical volunteers who have been systematically trained can undertake part of outdoor medical rescue work. Pre-activity training and regular re-training of medical volunteers can ensure the safety of outdoor activities.

Experimental Investigation of Characteristics and Development of Nonlinearity Models for FR1-Range Radio-Frequency Amplifiers

Experimental studies of nonlinear properties of low-power radio-frequency amplifiers similar to those used in 4G/5G mobile communication equipment of the FR1 frequency range are carried out. The measurements of the characteristics of the amplifiers are performed by using the double-frequency testing technique at frequencies of the n7 band (2500–2570 / 2620–2690 MHz), which is allocated in Belarus for 4G mobile communication systems, and the n78 band (3300–3800 MHz), which is planned to be used in Belarus for 5G mobile communications. Based on the results of the measurements of double-frequency characteristics of the amplifiers, their single-tone amplitude characteristics, as well as two-tone characteristics and values of the dynamic range of 3-, 5-, 7-, and 9th order intermodulation in the first harmonic zone, high-order polynomial models of transfer characteristics of the investigated amplifiers are synthesized. The synthesized models are suitable for use in a wide dynamic range of input signals in case of simultaneous modeling of nonlinear effects of all kinds that pose a danger to radio reception in a complex electromagnetic environment created in the frequency bands of mobile (cellular) communications: both “subtle” effects (intermodulation) and “rough” effects (desensitization, cross-modulation). When using the technology of discrete nonlinear analysis of the behavior of radio equipment in a complex electromagnetic environment, the obtained models provide high efficiency of simulation and quantitative analysis of nonlinear processes and radio interference occurring in 4G/5G/6G radio equipment and networks in a complex electromagnetic environment.

ANALYSIS OF DEVELOPMENT TRENDS IN MODERN BUSINESS COMMUNICATIONS

Advanced communication techniques are used to organize fixed-user access to corporate communication network (CCNs) resources, with the ability to quickly change the encoding speed during network overloads. Estimating the probability of a denial of service caused by a lack of free channel resources at Access Network was one of the research's aims. IP based network enable the delivery of different services. Primary determinants of users' subjective quality evaluation of communication: data transmission: fast, without errors or failures; video communication: high-quality images, no delays; audio communication: no voice distortion, no call failures. Important to network operators to make effective use of their own resources while maintaining transmission quality standards. Control over metrics such packet loss ratio, delay variations, and latency is crucial. For certain corporate networks, the implementation of 5G mobile communication equipment holds great potential, especially in terms of enabling remote access for staff members. Simultaneously, concerns over unauthorized access to information and the risk of packet loss during transmission have become increasingly pressing. This paper discusses the effectiveness of Low-Density Parity Check (LDPC) codes and polar codes in variable length packet transmission in a 5G system. The modeling results of 5G communication system operation at a fixed value of packet loss are discussed.

GEODETIC RESEARCH OF THE SMOKESTACK TILT OF THE BOILER HOUSE ON KARNAUKHOVA STREET IN RIVNE

Smokestackеs are extraordinary and technologically important construction structures. Their safe operation is a prerequisite for long-term and trouble-free operation of a boiler house and the provision of heat to entire city districts. The purpose of this paper is to study the smokestack tilt of a boiler house using geodetic methods. The relevance of this research is in the fact that the smokestack tilt a dangerous factor that can lead to its destruction due to loss of stability or due to the force exceeding the maximum resistance. The destruction of such a structure can cause significant economic or even human losses.
 A preliminary calculation of the accuracy of geodetic work to determine the smokestack's tilt on M. Karnaukhova Street was performed. Based on the calculation results, an electronic total station Leica TCR 1205 was selected. A modified coordinate method was used to determine the position of a large number of points on the outer surface of the smokestack for each horizontal section. The measurement results are balanced by the parametric method of the least squares method. This method is implemented in the "Kren" software module developed by the authors.
 Three measurement cycles were performed in 2021, 2022, and 2023. The value of the tilt (about 200 mm) is quite noticeable for this smokestack with a bottom section diameter of 3.65 m. The smokestack is tilted in the direction from which the mobile communication equipment is installed. The balanced tilt value differs from the value calculated from the outermost observation points from the station. Tilt monitoring data should be considered as an integral part of the chimney building information system (BIM).

Административное противодействие поступлению запрещенных предметов на территории учреждений УИС

The article is devoted to administrative counteraction to the receipt of prohibited items on the territory of institutions of the penal system. The author notes that one of the important problems of ensuring the established order of serving a sentence is the transfer or attempt to transfer prohibited items, including mobile communications equipment, to the institutions of the penal system. The main directions of prevention of the admission of prohibited items on the territory of the institutions of the penal system are considered. The measures of administrative counteraction to the penetration of prohibited items to persons held in correctional institutions are proposed, taking into account the positive experience of individual GUFSIN (UFSIN) of Russia.

The Effect of Instant Messaging Social Media Platform Characteristics on Consumers’ Purchase Intention: An Empirical Study of WeChat

With the rapid development of mobile communication equipment, the significant role of social media platforms is realized in social media marketing. To determine the effect of instant messaging social media platform characteristics on consumers’ purchase intention, we collected WeChat user data and designed an empirical model based on the technology acceptance theory. Analysis of 388 qualified surveys revealed significant positive effects of instant messaging social media platform characteristics, such as social presence, media richness, immediacy of communication, privacy protection, and entertainment on customers’ purchase intention. This study aims to extend the scope of technology acceptance theory, providing practical ideas for firms and highlighting the prominent role of instant messaging social media platforms in marketing activities.

Excellent Terahertz shielding performance of ultrathin flexible Cu/graphene nanolayered composites with high stability

Electromagnetic interference (EMI) shielding at Terahertz (THz) frequency range attracts increasing attention due to the rapid development of THz science and technologies. EMI shielding materials with small thickness, high shielding effectiveness (SE), good flexibility and stability are highly desirable. Herein, an ultrathin flexible copper/graphene (Cu/Gr) nanolayered composite are prepared, which can reach the average EMI SE of 60.95 dB at 0.1–1.0 THz with a thickness of only 160 nm, indicating that more than 99.9999% of the THz wave power can be shielded. Furthermore, the Cu/Gr nanolayered composite also exhibits excellent oxidation resistance, with a 93.09% maintenance rate for EMI SE value after heating at 120 °C for 3 h in air, far higher than that of the bare Cu film (62.15%). Besides, the Cu/Gr nanolayered composite exhibits good mechanical flexibility and flexural fatigue resistance. The EMI SE value of the Cu/Gr nanolayered composite shows a maintenance rate of 98.87% even after 1500 times bending cycles, obviously higher than that of multilayer Cu film (93.07%). These results demonstrate that the ultrathin flexible Cu/Gr nanolayered composites with excellent shielding performance and good stability have a broad application prospect in THz shielding for wearable devices and next generation mobile communication equipment.

ACCOUNTANTS AND ICT: BEYOND THE FIGURES FOR SOCIO-ECONOMIC CHANGE

This paper fosters the importance and need of international cooperation for use & promotion of Information and Communication Technologies for economic change in Nigeria among professional accountants. The concept of “Information Society” has made it imperative that no country can develop without involving and focusing on regional and global development perspectives. Collaboration has become the key word. When we talk of integrated socio-economic change, it takes into account many areas which can benefit from faster access and enhanced productivities by using ICT. Some case studies on use of ICT for different initiatives within Nigeria are reviewed and conclusions drawn on how it does support the socio-economic change and development, which may be similar and bear lessons for other developing countries. The supply side of ICTs has increased substantially in Kenya. For example, the number of mobile phone subscribers has more than tripled over the past five years, while FM radio stations have proliferated all over the country. There has been a lot of enthusiasm on internet usage with the landing of three undersea fibre optic cables in Lagos and their subsequent operationalization. Marxs of mobile phone service providers and communication equipment now dot both the rural and urban landscapes, and advertisements for some form of ICTs are common on billboards along major highways and roads.

Beidou-GPS dual mode positioning of mobile communication equipment based on Android platform

With the rapid development of science and technology, positioning technology has been widely used in people’s daily lives and related scientific research activities. However, the traditional positioning system mostly uses GPS for positioning, and then transmits the positioning information to the remote server through GPRS / GSM, but it is not applicable in remote mountain areas where some base station signals cannot reach. Moreover, the accuracy of single GPS positioning is difficult to be guaranteed. This paper mainly studies the design of Beidou-GPS dual-mode positioning system based on Android platform mobile communication equipment. First, analyse the composition of the satellite positioning system and design the overall architecture of the Beidou-GPS dual-mode positioning system for mobile communication equipment. Then, it analyses the most important star selection algorithm in dual-mode positioning technology, and proposes an improved star selection algorithm based on azimuth. Second, build the overall architecture of the Android platform for mobile communication devices based on dual-mode positioning. Finally, by comparing with the traditional star selection algorithm, the proposed improved positioning algorithm is experimentally verified. Simulation experiment results show that the proposed dual-mode positioning algorithm has high accuracy and can meet the real-time requirements of the system.

Research on Intelligent Networking Automotive Technology and Information Security Based on CAN Bus

With the advancement of information technology, the role of vehicles in people’s lives is no longer just a means of transportation. It is also a carrier of mobile communication equipment. The emergence of the Internet has provided a new direction for the development and upgrading of automobiles. Modern information technology and Internet technology are combined with traditional vehicles to realize the intelligent advancement of automobiles. The ultimate goal of developing smart cars is to achieve driverless driving. With the research and development of intelligent networked vehicles, the problems in vehicle information security are gradually increasing. Based on CAN bus, this paper studies intelligent networking automotive technology and vehicle information security issues, and contributes to the development of intelligent networked vehicles.

Heterogeneous mobile network access control technology based on mutual trust mechanism

With the popularization of mobile communication equipment, the application scope of heterogeneous mobile networks is expanding. The diversity of network types and access methods of heterogeneous mobile networks also increases the number of security problems that exist in the network. In order to ensure the security of the heterogeneous mobile network, it is necessary to perform effective authentication and status monitoring on the mobile communication device requesting access to the heterogeneous mobile network. To this end, this paper proposes a heterogeneous mobile network access control technology based on mutual trust mechanism. Firstly, this technology designs a network system model based on mutual trust system. In this network structure, the mobile communication node needs to pass the verification of the security service system before access the network, which guarantees the security of the heterogeneous mobile network to a certain extent. In order to meet the network service quality requirements of mobile communication nodes, this paper adopts a naive Bayesian-based machine learning method to select the optimal access network in heterogeneous networks for mobile communication nodes. In order to prevent malicious nodes in abnormal state from destroying network security, this paper adopts the hidden node detection method based on hidden Markov model. The security service system is suspended to provide a trust service for the detected abnormal node, to make the security service system stop providing trust services for exception nodes and the exception nodes unable to continue using network services. In the simulation experiment, the security analysis of the algorithm and the effectiveness evaluation of the performance were carried out.

Intelligent monitoring system for smart road environment

Abstract The article considers the results of research received by the authors in the process of developing and implementing the components of an intelligent monitoring system. The system is designed to collect and process big data on road incidents from photo-radar complexes. Monitoring system is the main part of the Smart Road Environment. The authors propose a convergent model for processing big sensor data, which includes three layers using fog, cloud and mobile computing technologies. Within the framework of the convergent model, the multi-agent approach for data processing is implemented. In the process of working on the project, software agents that perform data collecting, cleaning, clustering, comparing time series, retrieving data for visualization, preparing charts and reports, performing spatial analysis, etc. Big sensor data and other heterogeneous information from other sources (weather stations, video surveillance systems, mobile communication equipment, built-in car navigation equipment etc.) are collected. The results of data processing mining are presented. The comparison of time series of traffic accidents and time series of meteorological factors is established, that the presence of factors to become determinants for an abnormal change in the traffic situation in controlled areas.

Software Testing Method Based Mobile Communication Equipment of Maritime Satellite

Focusing on the different performance of communication links between satellite and mobile terminals, this paper creates an adaptive channel model for satellite mobile communication, which can accurately reflect the multipath, shadowing and other problems in signal propagation and effectively forecast and evaluate the modulation, demodulation, coding and constellation distribution of satellite mobile communication systems. Then, the author put forward a software testing method for mobile communication equipment of maritime satellite. The proposed method achieves comprehensive verification and evaluation from the aspects of equipment applicability, reliability, durability, etc. The research findings provide a software test approach and the evaluation basis for improving the performance of communication equipment.

Nonlinear Three-Port Representation of PAs for Embedded Self-Calibration of Envelope-Dependent Dynamic Biasing Implementations

This paper proposes a three-port power amplifier (PA) representation based on distinct sets of nonlinear complex polynomials that describe a combiner, a nonlinear baseband-to-RF converter and a nonlinear RF amplifying function, for processing the PA's input modulated signal and any envelope-dependent dynamic biasing signal. This novel representation of PA nonlinearities simplifies computation and renders possible analytical formulations to describe a 3-port PA system. It allows accurate prediction of the PA's output distortion components as a function of an input multi-tone excitation and a multi-tone dynamic biasing signal. The representation is intended for a context proposed, to the best of the authors' knowledge for the first time, and envisioned as promising for future mobile communication equipment - the automatic optimization of linearity performance in Radio Frequency Integrated Circuit (RFIC) PAs under any modulated excitation and employing envelope-dependent biasing, through implementation of embedded self-calibration within the transmitter front-ends. In this context, the representation introduced here compares favorably in terms of accuracy with respect to Volterra-based approaches and allows a simpler characterization, while the literature often points to the complexity inherent to Volterra-based approaches. The proposed representation allows the optimization of the PA's dynamic biasing for linearity improvement from one mobile unit to another through embedded self-calibration starting from quasi-static measurements alone of the PA's input/output power. Its applicability is highlighted through benchmarking against experimental results demonstrating accurate PA characterization for multiple PA platforms under different dynamic biasing techniques. In one implementation using an industry-designed GaAs PA, it accurately predicts the dynamic biasing adjustments to achieve more than 4dB reduction in the output intermodulation distortion (IMD3). In another implementation using the recently introduced positive envelope feedback linearization scheme, the proposed representation allows, for the first time, analytically predicting the condition of closed-loop stability and the requirements for the feedback components with experimental verification.

An Effective Data Transmission Algorithm Based on Social Relationships in Opportunistic Mobile Social Networks

With the popularization of mobile communication equipment, human activities have an increasing impact on the structure of networks, and so the social characteristics of opportunistic networks become increasingly obvious. Opportunistic networks are increasingly used in social situations. However, existing routing algorithms are not suitable for opportunistic social networks, because traditional opportunistic network routing does not consider participation in human activities, which usually causes a high ratio of transmission delay and routing overhead. Therefore, this research proposes an effective data transmission algorithm based on social relationships (ESR), which considers the community characteristics of opportunistic mobile social networks. This work uses the idea of the faction to divide the nodes in the network into communities, reduces the number of inefficient nodes in the community, and performs another contraction of the structure. Simulation results show that the ESR algorithm, through community transmission, is not only faster and safer, but also has lower transmission delay and routing overhead compared with the spray and wait algorithm, SCR algorithm and the EMIST algorithm.

Multiple‐frequency digital phase‐locked loop based on multiphase clock divider with constant pulse interval

AbstractIn the mobile communication equipment, the clock generator for driving each system is required to have a fast pull‐in time, multiple signals of constant pulse interval, synchronization range, low output jitter, and wide lock‐in range characteristics. In this paper, multiple‐frequency multiphase clock digital‐controlled phased‐locked loop (MC‐DCPLL) is proposed. In this loop, the pulse width error of the multiplied output signal is a time within one phase difference of the multiphase clock regardless of the multiplication ratio. The output jitter in the steady state is always within one phase difference of the multiphase clock. Since it is a control method by dividing ratio changeable type, the lock‐in range is extremely wide. Also, the initial pull‐in time is always completed in one cycle of the input signal without being influenced by the multiplication ratio. It is clarified by theory and simulation that these characteristics can be obtained. From the above, the versatility of the proposed multiple‐frequency MC‐DCPLL is extremely high, and it can be expected to be used for clock sources, and so on, in various mobile communication equipment systems.

Multiple Frequency Digital Phase-Locked Loop Based on Multi-Phase Clock Divider with Constant Pulse Interval

In the mobile communication equipment, the clock generator for driving each system is required to have a fast pull-in time, multiple signal of constant pulse interval, synchronization range, low output jitter, and wide lock-in range characteristics.

GPS Positioning of Mobile Communication Equipment Based on Android Platform

With the rapid development of computer technology and network communication technology, the demand for convenient and quick access to location information is becoming stronger. The GPS positioning system of mobile communication equipment of Android platform has been favored by most users due to its unique convenience and rapidness as well as the superior system stability. Through the research and analysis of the application of Android platform to build the GPS positioning system on mobile communication equipment, this paper makes details description on how to improve the precision of the GPS positioning data and foresees the broad development prospect of the GPS positioning system. GPS positioning technology provides users with the initial location information, making it better for users to experience the location-based services such as AutoNavi, Baidu map, car navigation, etc., which greatly facilitate people's lives.

Certificateless searchable public key encryption scheme for mobile healthcare system

As mobile communication technology develops, mobile healthcare system (MHS) is becoming a hot topic in academia and healthcare industry. MHS refers to providing medical services through mobile communication equipments. However, it faces many challenges, such as the finite storage, computing power and communication capabilities of MHS devices. To address this problem, the concept of cloud-based MHS has been proposed recently. Meanwhile, healthcare data outsourcing to cloud raises privacy and confidentiality concerns. In order to protect data security, we present an efficient certificateless public key encryption with keyword search (CLPEKS). Security analysis indicates that our scheme is secure resist chosen keyword and keyword guessing attacks in random oracle model. The computation costs of KeyGen, CLPEKS, Trapdoor and Test phases decreased by 84.68%, 55.04%, 36.1% and 28.73%, respectively, compared with Peng et al.’s scheme.

Output Power Levels of 4G User Equipment and Implications on Realistic RF EMF Exposure Assessments

The aim of this paper is to present results on output power level distributions of 4G user equipment (UE) using data applications based on a very large number of samples collected over seven days in a long-term evolution (LTE) operating network. The output power data have been obtained through network-based measurements conducted for about 7000 UE connected to 41 LTE radio base stations located in rural, suburban, urban, and indoor environments in Sweden. More than 300 000 power samples were collected. In rural environments, the 95th percentile time-averaged output power values were found to be 2.2% of the maximum available power for LTE UE, while the corresponding values were less than 1% in other environments. The mean output powers in all the environments were found to be less than 1% of the maximum available output power. These values are in line with results obtained for 3G UE despite an almost tenfold increase in the achievable peak data throughput. The findings show that knowledge on realistic power levels is important for accurate assessments of the radio frequency electromagnetic field exposure from mobile communication equipment.