Communication Base Station Research Articles

Design of Wireless Communication Base Station Monitoring System Based on Artificial Intelligence and Network Security

With the rapid popularization of the network, under the increasingly complex network security situation and the increasingly prominent network security problems, network security occupies an important field in the wireless communication base station monitoring system, and has become a hot research direction. It is to design a wireless communication base station monitoring system based on artificial intelligence and network security. In the experiment, using the supervised machine learning algorithm, the program of the wireless communication base station monitoring system is designed by setting the working frequency of the GSM-based wireless communication system to the wireless communication base station monitoring system.

Clustering Optimized Genetic Algorithm-Based 5G Communication base Station Site Selection

To minimize the negative impact of the base station construction, and at the same time make the base station cover as many users as possible, the Genetic Algorithm optimized Density-Based Spatial Clustering of Applications with Noise (DBSCAN) method is proposed. Initially, the number of points is fixed and encoded into a gene sequence with 4 different features at each point. After that, the process of the DBSCAN is stated and then it constructs the cluster adaptation function. Then, with the combination of the cluster adaptation function and the coverage function, it can select the individual, cross the gene sequence, and change the slight value of the sequence. Ultimately, by iteration, it can output the optimal point location and the result shows that the optimal coverage is 95%.

Influence of Spatial Selectivity of Radiation of Mobile Communication Base Stations on the Level of Electromagnetic Background Introduced by them

Radio frequency electromagnetic radiation from base stations is the main source of electromagnetic background generated by mobile (cellular) communication systems in residential areas; its intensity makes a significant contribution to the level of electromagnetic pollution of the habitat and determines the level of electromagnetic safety of the population. The previously proposed technique for estimating the average intensity of this background, based on the analysis of the territorial intensity of mobile traffic, takes into account the spatial selectivity of base station radiation in a simplified form by introducing the radiation directivity parameter U, equal to the inverse of the number of base station service sectors, assuming that the width of the main lobe of the radiation pattern is equal to the width of this sector and without taking into account the radiation directivity in the vertical plane, which determines the pessimistic nature of these estimates. The paper presents a refined analysis of the values of the parameter U for a two-level models of antenna radiation patterns, which reflects the real values of the width of their main lobes in horizontal and vertical planes, the relative levels of side lobes and the ratio of radiation power of the main and side lobes. The analysis was performed both for stationary sector antennas of cellular communication systems and for adaptive phased antenna arrays of 4G/5G systems capable of providing service using narrow beams. The analysis showed that the value of the U parameter of sector antennas is 5–15 dB less than the inverse of the number of sectors of base stations, and for narrow beams of adaptive antenna arrays, this difference reaches 20 dB. If tilt angles of main lobes of antenna radiation patterns with respect to the horizon are less than 30°, then at estimation of the average electromagnetic background intensity the inverse of their antenna gain in the main lobe can be used as the U parameter value of the spatial selectivity (directivity) of base stations radiations.

Research on infrared small target segmentation algorithm based on improved mask R-CNN

The task of segmenting small infrared targets, which have few pixels and weak features, has been a difficult problem in the field of small target image processing. Small targets not only exist in general images, but also widely exist in drone cameras, communication base station cameras, rescue cameras, and vehicle cameras. Research on small target segmentation algorithm is very important for analyzing and utilizing these images, and it also has important application value in security, traffic, and rescue. Traditional small target segmentation algorithms are able to segment objects with simple target contour edges and large differences in signal strength. The traditional algorithm often has a high false detection rate and missed detection rate when facing several targets with weak signal strength. It does not perform well in complex scenes. In this paper, we introduce an infrared small target segmentation scheme facing multiple types and numbers of targets. This paper also produces an infrared UAV and pedestrian dataset for validation. Experiments show that the optimized algorithm has a better detection effect on targets in complex scenes.

Electric field characteristics of shared towers and electric field distribution characteristics near 5G base stations

With the continuous promotion of domestic 4G network construction and the gradual arrival of 5G networks, the requirements of mobile communication networks on capacity and coverage are constantly improving, and the number of communication base stations is also increasing. Therefore, the “shared tower” with the function of a communication base station added to the existing high-voltage transmission line tower is becoming a new resource-sharing mode. There is no systematic study on the installation location of the shared tower base station on the high-voltage tower, which is not conducive to the application and promotion of “shared tower”. In this paper, the finite element simulation model of the tower installed with the base station is built. The electric field distribution near the tower with the base station, the electric field distribution characteristics under different base station installation quantities and different positions of the base station are mainly studied, and the electric field distribution near the surface of the base station is obtained. Combined with the electrical safety distance limit of communication equipment and iron tower, the influence of the installation location and quantity of the base station on the electric field near the base station is evaluated.

Analysis and research on the resonance of mobile phone shielding cabinet

In order to cut off the connection between the mobile terminal and mobile communication base stations or Wi-Fi, it is necessary to improve the electromagnetic shielding efficiency of the mobile phone shielding cabinet. This paper analyzes the resonant characteristics of mobile phone shielding cabinets. The test method of electromagnetic shielding has been introduced. Through Maxwell wave equation and boundary conditions, the cavity resonant frequency of every small drawer on the mobile phone shielding cabinet has been derived, and the rectangular cavity research model was established. Using the high-frequency finite element method (FEM) simulation to calculate the cut-off frequency of the first 10-order high-order mode in the cavity, the resonant standing wave field distribution of every small drawer on the mobile phone shielding cabinet has been analyzed. This paper can offer a theory instruction for the product design of mobile phone shielding.

Treatment and Disposal of Other Medical Wastes based on Bluetooth and LoRa Wireless IoT

With the maturity of the Internet of Things technology, medical institutions have established a positioning and sensing wireless IoT platform for the entire medical institution by using technologies such as Bluetooth positioning beacons, LoRa communication base stations, positioning and map engines. The intelligent medical waste collection and transfer vehicle integrates the wireless Internet of Things platform in the hospital based on 4G/5G modules, Bluetooth positioning terminals, electronic weighing and other technologies. An information-based, intelligent, and visualized "smart medical waste" management system covering all aspects of medical waste generation, collection, temporary storage, transfer, and disposal has been established in medical institutions. This set of solutions can greatly reduce the number of communication base stations deployed in hospital indoor buildings, the number of weak current construction and access switches in hospitals, save a lot of unnecessary costs for weak current construction and access switches and meet the real-time needs of intelligent medical waste collection and transfer vehicles such as real-time positioning, real-time tracking, video linkage, trajectory playback, and transfer route deviation alarms, which have certain reference significance in the practice of intelligent medical waste construction technology in hospitals based on smart IoT. The article describes one case of implementation of the technology in a university Hospital.

Highway Vehicle Route Reconstruction Using Sparse and Noisy Communication Base Station Fingerprints

The current application of highway toll system generally uses the Dijkstra algorithm to calculate the shortest path of vehicles from the entrance to the exit to charge. This means that managers have no way of knowing the exact route of vehicles. Also, different routes of highways are often funded and operated by different investors. To address this problem, this article presents a new algorithm to reconstruct trajectories from sparse and noisy fingerprint signals from communication base stations identifications (CBSIDs), with practical application in a high-speed toll collection system in Hubei Province, China. In this solution, we use an inexpensive device that collects signal fingerprint identification numbers from CBSIDs at a low sampling rate. These CBSIDs are then matched with a special CBSID-anchor radiomap, converting the sequence of CBSIDs into a sequence of candidate anchors (toll stations and intersections on highways). Finally, a route mapping algorithm is run to process these candidate anchors and to generate the complete driving route. In the experiment on both simulated and field routes, results show that the proposed algorithm can effectively reconstruct the driving routes of vehicles. The upgraded toll collection system meets the needs of efficient motorway investment, maintenance, and management.

Lightning Hazard Assessment in Hainan Island Based on Hierarchical Analysis Model

According to the lightning monitoring data of Hainan Province from 2011 to 2020,eight cities in Hainan Province were selected as the evaluation units.Combined with the statistics of population, lightning weather, economic characteristics and land area of each city, the population density, GDP value, thunderstorm days, illiteracy level and lightning frequency (density) of each city were selected as risk assessment indicators, and the evaluation model was established by AHP. Get the weight of each index and calculate the lightning risk disaster index of each city according to the numerical value of each index of each city. After consulting relevant materials, it is found that the construction of communication base stations will also induce lightning disaster accidents, and the evaluation results of each city will also be affected by the number of communication base stations in the region, so the correctness of the results also indicates the rationality of the evaluation method.

Miniaturized Broadband Dual-Polarized Dipole Antenna Based on Multiple Resonances and its Array for Base-Station Applications

A novel bandwidth enhancement method using loading multiple parasitic structures to realize broadband miniaturized antenna is proposed. Based on the proposed strategies, one miniaturized wideband dual-polarized dipole antenna covering LTE/CDMA/GSM bands (690–960 MHz) for base-station application is designed. The antenna consists of two folded bowtie-shaped dipoles fed with a pair of crossed baluns, and is further loaded on a ceramic block with high permittivity ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\varepsilon$ </tex-math></inline-formula> ) for miniaturization. A parasitical square loop is loaded for bandwidth enhancement at a lower frequency. In addition, four split rings with a small square loop are firstly adopted for antenna resonance tuning, the impedance bandwidth is thus improved effectively. The antenna size is only <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.18\,\times \,0.18\,\times \, 0.22\,\,\lambda _{0}$ </tex-math></inline-formula> at the center frequency. The measured result of the fabricated prototype exhibits a relatively large operation bandwidth of 32.73% (VSWR < 1.6) with stable radiation patterns and relatively flat broadside gains. Moreover, to verify the feasibility of the proposed miniaturized antenna element in the base-station application, an array of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$2\,\times \, 4$ </tex-math></inline-formula> is further designed. The measured results of the array indicate isolation over 20 dB with an impedance bandwidth of 32%. Due to the good performance and compact feature, the proposed miniaturized broadband antenna element can find large application potential in multiband wireless communication base stations.

Environmental-economic analysis of the secondary use of electric vehicle batteries in the load shifting of communication base stations: A case study in China

Frequent electricity shortages undermine economic activities and social well-being, thus the development of sustainable energy storage systems (ESSs) becomes a center of attention. This study examines the environmental and economic feasibility of using repurposed spent electric vehicle (EV) lithium-ion batteries (LIBs) in the ESS of communication base stations (CBS) for load shifting. Methodologically, life cycle assessment (LCA) and net present value (NPV) are used to evaluate the environmental and economic performance of such system, respectively. Comparing with the conventional system without load shifting and the use of new LIBs in CBS, our analysis indicates that the proposed system is economically appealing, saving 17.6 % of life cycle cost. Nonetheless, the environmental performance of our system is almost identical to the conventional one, due to the relatively low round-trip efficiency of spent EV LIBs. Sensitivity analysis suggests that the differences of peak and valley electricity prices determine the economic potential of this system, and cleaner energy sources such as nuclear power could largely improve its overall environmental performance. By highlighting the importance of improving round-trip efficiency and using clean energy resources, our work offers implications for stakeholders like policymakers and researchers.

A 3‐D ‐printed Luneburg lens antenna with consistent multibeams based on quasi‐pyramid structure

A wide-scanning dual-polarized Luneburg lens antenna based on the quasi-pyramid structure is proposed. To achieve beam consistency, 18 identical quasi-pyramid sections are employed to approximate a spherical lens antenna, and each section is divided into 12 layers. The 6-stepped gradient permittivity index is achieved by the diced ring-type periodic unit cells in accordance with the Effective Medium Theory. Each quasi-pyramid is incorporated with the same connecting structure to form an integrity. And a dielectric rod is penetrated parallelly to the center axis of the lens, thus improving the robustness of the overall structure. The radius of the whole lens is merely 0.88λ0. The spherical Luneberg lens antenna is fabricated and measured, with an impedance bandwidth of 45.5%, a measured peak gain of 15.4/15.1 dBi and a cross-polarization level of higher than 17/17.5 dB. Placing the feed antenna at different locations during the measurement, results attest that those beams possess an excellent consistency. The multibeams are able to achieve an ultra-wide beam coverage of 165°, promising it a serviceable candidate for mobile communication base stations and wireless networking.

Recent advances of metal–organic frameworks‐based proton exchange membranes in fuel cell applications

AbstractIn recent years, proton exchange membrane (PEM) fuel cell (FC; PEMFC) has been widely studied and gradually applied to vehicle power supply, portable supply, communication base station backup, emergency power supply, and so on. Especially in new energy vehicles, PEMFC has absolute advantages and a broad market. PEM, which is the core component of PEMFC, has a close correlation between its property and the performance of FC. Therefore, developing excellent PEMs is the focus of researchers. Metal–organic frameworks (MOFs) composed of metal ions/clusters and organic ligands have attracted extensive attention in the field of proton conduction. The hybrid membranes formed by MOFs and polymers show excellent performances and design concepts, which have great prospects in commercial application. This paper summarizes the research progress of MOFs‐based hybrid membranes as PEMs applied in hydrogen–oxygen FCs and direct methanol FCs, in which the different polymers used as substrates are also summed up.

Segmentation of the communication tower and its accessory equipment based on geometrical shape context from 3D point cloud

ABSTRACT Communication tower (CT) and its accessory equipment (AE) such as radio frequency equipment (RFE) and antenna, are essential in providing highspeed and stable mobile network services. It is necessary to routinely monitor the security and stability of CT and AE for seamless communication. There is limited research on fine segmentation of communication base station objects. This paper proposes a method for accurately segmenting the point cloud of the CT and AE from Terrestrial Laser Scanning (TLS) data. At first, the CT point cloud is accurately segmented based on region growing and Random Sample Consensus (RANSAC). Then, the point cloud of pole-shaped apart is extended to a certain distance to obtain the buffer point cloud containing AE. Normal Differential (ND) clustering is employed to obtain several groups of clusters containing planes, and calculate each plane's filling rate and size. Finally, the cluster type (such as antenna, RFE, or other) is distinguished. The experimental results demonstrate that the point-based average F1-score of CTs is 98. 70%, the point-based and object-based average F1-scores of antennas are 96. 09% and 97. 93%, and the corresponding values for the RFE are 89. 89% and 90. 00%, respectively, indicating the optimal performance of the proposed method.

Exploration of the Common Problems and Suggestions in the Construction Management of Wireless Communication Base Station Project

Exploration of the Common Problems and Suggestions in the Construction Management of Wireless Communication Base Station Project

Simplified Gate Driver Design Technique for Multi-MHz Switching GaN FETs in Three-Level Buck-Based 4G/5G Envelope Tracking

Multi-MHz switching frequency converter-based envelope tracking dc power supplies are widely adopted in modern 4G/5G communication base stations to improve the efficiency of radio frequency power transmitters. The switching loss of buck converter at MHz switching frequency increases with the input dc voltage. To obtain higher output voltage range without much compromise on the efficiency, multilevel converters with discrete low voltage gallium nitride (GaN) field-effect transistors (FETs), switching at multi-MHz frequency, are used. However, the gate driving circuit and PCB layout of a multilevel buck converter are complex and occupy major portion of the board when compared with the power GaN FETs. This article proposes a simplified gate driving technique in a cascaded bootstrapping architecture for a three-level buck converter with reduced number of components that can support up to 40 MHz switching frequency. The converter can reproduce any reference envelope signal with a maximum bandwidth of 8 MHz and output voltage variation from 6 to 42 V. Hardware prototype is developed, and experimental results are presented to validate the concept.

Mobile Communication Network Site Planning Research Based on Simulated Annealing Algorithm Optimization Model

With the development of 5G network, it becomes a hot topic to reasonably plan the siting of communication base stations in the weak coverage area of 5G network. In this paper, we take improving the coverage of service volume and reducing the cost of building base stations in the weak coverage area as the target of siting, and select base station sites among 2500×2500 points in a given area under ideal conditions and actual conditions, respectively, and use the less time-complex clustering method to cluster all weak coverage points. In order to improve the feasibility of the model in practical applications, we try to develop the base station site selection scheme that benefits the most for the 5G construction company by setting up a multi-objective planning model based on multiple constraints. On this basis, the conditions of the multi-objective planning model are changed and optimized to obtain a new multi-objective planning model based on the requirement that the communication coverage of base stations is fan-shaped in real life, and the simulated annealing optimization algorithm based on greedy thinking is used to optimize and solve the listed multi-objective planning model to obtain a new station site plan.

Optimization Algorithm of Communication Resource Allocation in a Complex Network Based on an Improved Neural Network

The traditional optimization algorithm of communication resource allocation in a complex network has the disadvantage of weak antijamming ability, and the communication quality decreases obviously when the number of users is large. In China’s large urban network applications, mobile phones and other networks can have problems such as reduced network efficiency when there are more access users at some communication base stations, thus affecting user network usage. An optimization algorithm of communication resource allocation in the complex network based on an improved neural network is proposed. Increase inertia improves the traditional BP neural network algorithm, using the average path length, clustering coefficient, and connectivity distribution index analysis of the complex network; the improved Hopfield neural network is utilized to confirm each user volume size; it is concluded that their users are able to get the number of subchannels, through the instantaneous channel coarse pair gain dynamic channel allocation, calculating bit load matrix at the same time, minimize transmission power, and achieve bit loading and power allocation and communication resource allocation optimization. Experimental results show that the proposed method has better application performance by introducing the improved neural network and suppressing the external interference on the basis of enhancing the communication effect.

Secure PD-NOMA with Multi-User Cooperation and User Clustering in Both Uplink and Downlink PD-NOMA

The power domain non-orthogonal multiple access (PD-NOMA) scheme has gained tremendous interest with the multiple access behavior for fifth-generation (5G) wireless communication. Although the overall performance is improved through accurate power distribution among users’ signals, it depends on the user clustering strategy. Moreover, the PD-NOMA communication is not completely secured due to its broadcast nature, which is still a major problem. This paper presents a novel low-complexity short code-based technique utilized by the registered users and the 5G base station (gNodeB) for communication. By doing so, the PD-NOMA scheme is made secure from unregistered users or eavesdroppers. We proposed a three-step user clustering strategy that selects the best cluster among all the possible clusters to improve the overall performance. The proposed clustering strategy achieves a low outage probability in PD-NOMA systems. Moreover, it uses a multi-user decode and forward cooperative relaying scheme with PD-NOMA (Cop-PD-NOMA) to increase the coverage range of the gNodeB. In the multi-user Cop-PD-NOMA, the strong users (near users) are used as relay stations to aid the weak users (far users) by the decode and forward (D&amp;F) technique. The proposed work provides a secure PD-NOMA network and the most effective user clustering approach during validation. The bit-error-rate (BER) comparisons demonstrate that multi-user cooperation outperforms single-user cooperation in Cop-PD-NOMA communication.

Polarization-Flexible and Frequency-Scanning Leaky-Wave HMSIW Antenna for Vehicular Applications

To achieve multifunctional communication and safe driving of a vehicle, a half-mode substrate-integrated waveguide (HMSIW) leaky-wave frequency-scanning antenna with flexible polarization is proposed in this article. It includes two linearly polarized interdigital slot antennas, a compact directional coupler, and microstrip transition lines. It can generate either linear polarization (LP) for base station communication or circular polarization (CP) for satellite navigation by configuring the means of excitation. Its radiation beam can be continuously steered with varying frequency in either the LP or the CP state, which is of benefit to safe vehicular driving. In addition, the use of the HMSIW structure reduces the size of the antenna by almost one-half in comparison with the full SIW structure. Measurements were performed on antenna scattering parameters, radiation patterns, gain, and axial ratio (for CP states); the results show good agreement with the simulated results. With its low profile, low weight, low cost, and capability for continuous frequency scanning and variable polarization states, the multifunctional antenna could be extensively used for adapting to changes in environmental conditions or system requirements.