Station Communication Research Articles

Implementation and analysis of MultiCode MultiCarrier Code Division Multiple Access (MC–MC CDMA) in IEEE 802.11ah for UAV Swarm communication

Utilization of flying platforms like Unmanned Aerial Vehicles (UAVs) is progressively increasing in our daily lives. Key characteristics such as flexibility, mobility and adaptive altitude, make UAVs particularly suitable for application in areas such as crop management, goods delivery, public safety and real-time video surveillance of public places to assist in terrestrial networks. IEEE 802.11ah is a WiFi brand Internet of Things (IoT) technology, with properties of suitable data rates, flexibility in channelization, Multi Input Multi Output (MIMO) capability and low power consumption etc. Compared to the existing wireless technologies, IEEE 802.11ah is a suitable choice in terms of data rate and performance. In this research, MultiCode (MC) MultiCarrier (MC) Code Division Multiple Access (CDMA) is incorporated in the Physical (PHY) layer of IEEE 802.11ah to meet the differential requirements of range and throughput of UAV to UAV and UAV to Ground Control Station (GCS) communication links for UAV swarm. Depending upon the nature of data transmitted between the UAVs and GCS, suitable Modulation and Coding Schemes (MCS) are selected for multiple bandwidths. Performance analysis of MC–MC CDMA in IEEE 802.11ah has been performed in Additive White Gaussian Noise (AWGN). It has been observed that an increase/decrease in the modulation order directly affects data rate, with a compromised performance at higher modulation order.

Automatic wireless Monitoring and Controlling of Greenhouse using multiple sensors

Many parameters like temperature, soil moisture, light intensity, Humidity, Carbon dioxide (CO2) leads to the healthy growth of plants in greenhouse environment. Observing only few of those leads to improper growth of plants and minimize the yields. Every grower cannot visit the field and observe the parameters continuously. In order to monitor the parameters and give the approximate control to the greenhouse, we proposed this system. This system continuously monitors the plants and communicate the information to the grower through wireless Sensor Network (WSN), thus reducing the risk of staying at the field. The proposed system has three stations - Transmitter Station (TS), Control Station (CS), and Communication Station (CMS). The ZigBee plays a major role by enabling communication between the three stations. This implementation supports the farmers to simplify the management and to increase the crop production. The overall system has shown the benefits in price, volume, and strength.

Choosing Words Wisely: Residents' Use of Rhetorical Appeals in Conversations About Unnecessary Tests.

To characterize how residents employ rhetorical appeals (i.e., the strategic use of communication to achieve specifiable goals) when discussing unnecessary diagnostic tests with patients. In 2015, senior hematology residents from 10 Canadian universities participating in a national formative objective structured clinical examination (OSCE) completed a resource stewardship communication station. In this communication scenario, a standardized patient (SP) portrayed a patient requesting unnecessary thrombophilia testing following early pregnancy loss. The authors performed a thematic analysis of audio transcripts using a qualitative description approach to identify residents' rhetorical appeals to logic (rational appeals), credibility, and emotion. For persuasive communication, residents (n = 27) relied primarily on rational appeals that fit into 3 categories (with themes) focused on medical evidence (poor utility, professional guidelines and recommendations), avoidance of harm (insurance implications, unnecessary or potentially harmful interventions, patient anxiety), and reassurance to patient (normalizing, clinical pretest probability, criteria for reconsidering testing). Appeals to credibility and emotion were rarely used. In an OSCE setting, residents relied predominantly on rational appeals when engaging SPs in conversations about unnecessary tests. These observations yield insights into how recent emphasis within residency education on appropriate test utilization may manifest when residents put recommendations into practice in conversations with patients. This study's framework of rational appeals may be helpful in designing communication curricula about unnecessary testing. Future studies should explore rhetoric about unnecessary testing in the clinical environment, strategies to teach and coach residents leading these conversations, and patients' preferences and responses to different appeals.

Efficiency Evaluations Based on Artificial Intelligence for 5G Massive MIMO Communication Systems on High-Altitude Platform Stations

The key technologies for applying fifth generation in high-altitude platform station (HAPS) communication systems have many outstanding advantages, especially large-scale antenna array technology. HAPS communication systems have inherent advantages that can perfectly complement large-scale array antenna technology and solve the problems of many existing ground communication systems. The chances of long-packet data users and short-packet data users being serviced are different due to the differing data length of each user's packet. According to the user's channel environment and data length, the user with the smallest delay is selected for transmission. Dynamic and interdependent characteristics between systems and the evaluation of the efficiency of wireless resources are studied in this article. Game theory is applied to the evaluation of the wireless resource efficiency of the system, and an efficiency evaluation model is constructed. In addition, the efficiency of this preliminary work is verified by simulation.

Recognizing Automatic Link Establishment Behaviors of a Short-Wave Radio Station by an Improved Unidimensional DenseNet

It is difficult to recognize Automatic Link Establishment (ALE) behaviors of a short-wave radio station, if we do not acquire the radio station's communication protocol standard. A method is proposed to recognize different ALE behaviors by using an improved unidimensional DenseNet. In this work, we directly recognize ALE signals in physical layer without the radio station's communication protocol standard. Hence, we can avoid difficulties in demodulation, decryption and so on. Actually, the original DenseNet is used extensively in the field of computer vision, so the original DenseNet is firstly adapted for the unidimensional input. And then, two parallel dense blocks are used in our improved unidimensional DenseNet, which could improve the capability of network to extract ALE signals' deep features. The experimental results show that the proposed method is able to recognize different ALE behaviors of a short-wave radio station. And improved DenseNet has better recognition performance than simple DenseNet. The simple DenseNet only contains one dense block. Finally, the results of comparison experiments also show that some classic networks have worse performance in ALE behaviors recognition, such as LeNet-5, ResNet-34, and DenseNet-121.

Methodology for calculating the average time of entry into synchronism of stations of the system of quantum key distribution with sequential polling of fiber-optic line sections with decreasing length by the graphic-analytical method

A method is proposed for calculating the average time of entry into synchronism of stations of the system of quantum key distribution (QKD) with sequential polling of sections of a fiber-optic communication line (FOCL) with decreasing length. A diagram of states and transitions for a sequential search for a photon pulse is constructed. Analytical expressions are obtained for finding the probability of detecting a photon pulse, the average number of steps for entry into synchronism of stations, the variance of the number of steps and the average time for entry into connection. It is noted that when the FOCL is divided into sections with decreasing length, the level of dark current pulses (DCP) significantly decreases from section to section. The latter allows to reduce the probability of false alarms of the photodetector. The analysis of the results obtained showed that the time of entry into synchronism for the proposed algorithm is 3 times less than the time required for entry into communication of stations in the case of an algorithm-analogue. The results obtained indicate the possibility of increasing the length of the FOCL while ensuring the value of the synchronization error probability at the level of 0.01.

SIMULATION IN ASSESSING PATIENT COMMUNICATION SKILLS IN ACCREDITATION OF MEDICAL SPECIALISTS: APPROACHES, PROBLEMS, SOLUTIONS

Implementation of the Communication station at the practice-oriented stage of accreditation of medical specialists from the standpoint of the organization and scientific and methodological study of the assessment of communication skills with a standardized patient in simulated conditions of the practice-oriented stage of accreditation of medical specialists.

Fuzzy Relation Bilevel Optimization Model in the Wireless Communication Station System

Fuzzy Relation Bilevel Optimization Model in the Wireless Communication Station System

Method for Determining the Parameters of Interference Affecting the Input of the Repeater Trunk

Military satellite communication networks operate under the influence of enemy radio suppression systems. To suppress the network, it is necessary to put a deliberate interference either at the entrance of the trunk of the communication repeater, or at the entrance of satellite communication stations operating in this network. Taking into account the peculiarities of building a satellite communication network, the most likely effect is the radio-electronic suppression complex at the entrance of the repeater trunk. The article presents a method for determining the parameters of interference affecting the input of the repeater trunk

Methods for solving incorrect tasks of electrodynamic analysis of radiating structures based on chiral metamaterials

This article is devoted to the development of correct methods for electrodynamic analysis of single and multi-element radiating structures with substrates of chiral metamaterials. An approach to the electrodynamic analysis of such antennas based on the method of singular integral representations of the field and the method of surface impedances is proposed. A system of singular integral equations with respect to unknown distribution functions of current density over emitters is obtained. The proposed method was tested using the example of solving a test problem using the Feko software package. The prospects of using such ICs in MIMO systems are shown, which make it possible to increase their efficiency, in particular, to increase throughput. The effect of azimuthal scattering of electromagnetic waves is also presented, which can be used to create low-profile antennas of subscriber radio communication stations installed on mobile objects.

MIMO waveform design combined with constellation mapping for the integrated system of radar and communication

In this paper, we propose a novel technique to integrate the dual functions of radar and communication in a single platform, sharing the same frequency spectrum. The proposed technique utilizes the constellation mapping method to embed information symbols in the communication direction via transmit beamforming. By minimizing the integrated sidelobe level (ISL) for transmit beamforming, the system can achieve lower sidelobe level (SLL) for radar detection. The transmit level in the communication direction is controlled to ensure dependable communication transmission, taking into account the communication channel between the integrated platform and the communication station (i.e. communication distance and channel fading). We also investigate the communication performance in bit error rate (BER) with respect to angular error in transmit beamforming and resulting pointing error towards communication station. It is shown that our proposed method has better performance in BER and lower probability of interception (LPI) for communication transmission. Simulation results are presented to verify the theoretical derivations.

Multi-beam coverage and beamforming technology for high altitude platform station communication system

Multi-beam antenna technology can effectively mitigate the impact of deep fading caused by multipath propagation on communication quality through spatial diversity and increase the reliability of wireless mobile communication systems. At the same time, the multi-beam antenna with beamforming algorithm as the key technology can realize spatial division multiple access (SDMA) by automatically adapting the weight vector of the antenna array, enhance the expected value, and suppress the interference. A novel beamforming technology increases the inner circle beam width and reduces the outer ring beam width to minimize the difference between the internal and external cell link SNR. This study considers reducing the number of cells by reasonably allocating beams, which satisfies both the requirements of coverage link quality and the difficulty of forming antenna beams. This research subject applies the scheme and strategy of improving multi-beam antenna technology in the same system. Under the requirement of cell coverage and partitioning, the related technologies and strategies combining multi-beamforming technology and space-time block code technology can obtain high coding gain and diversity gain without sacrificing bandwidth and effectivelyx improve the wireless systematic capacity.

A multi-experiment approach to ascertain electromagnetic precursors of Nepal earthquakes

The experimental data obtained from three different techniques such as (i) subsurface VLF electric field measured with the help of a borehole antenna (ii) total electron content (TEC) of the ionosphere measured with a GPS receiver and (iii) VLF amplitude of subionospheric fixed frequency (f = 19.8 kHz) NWC (Naval Communication Station) transmitter signals monitored with SoftPAL receiver are analysed in relation to two major Nepal earthquakes occurred on 25 April (M = 7.8) and 12 May (M = 7.3), 2015. The VLF electric field data and fixed frequency VLF transmitter signal data are taken from Mathura and Agra stations in India whereas TEC data are taken from three IGS stations, one of which Lucknow (Lck3) is located in India and others Lhasa (Lhaz) and Wuhan (Wuhan) are located in China, all within 800 km from epicenters of two earthquakes except Wuhan which is located at about 2865 km. The results of the analysis indicate that while borehole and TEC data show anomalies in normal variations within 8–15 days prior to the earthquake of 25 April, the same occur within 5–7 days prior to the earthquake of 12 May. The subionospheric variations of VLF amplitude also show an anomaly 4 days before the later earthquake. Occurrence of these anomalies is examined critically in the light of local lightning and magnetic storms. However, these factors are not found to influence the data. A brief description of generation and propagation mechanisms of seismogenic emissions is also presented.

3D‐MIMO beamforming realised by AQPSO algorithm for cylindrical conformal phased array

Three-dimensional (3D)-MIMO beamforming realised by adaptive quantum particle swarm optimisation (AQPSO) algorithm for the 36-element cylindrical conformal phased array is proposed in this study. The cylindrical conformal phased array consists of 36 circularly polarised microstrip antenna elements with ultra-wideband and high gain characteristics. The conformal array is divided into 12 subarrays using reconfigurable technology, and each subarray produces six beams to cover the corresponding spatial area. The 3D-MIMO beam is formed by AQPSO, and the active element pattern data of array elements is introduced to AQPSO to improve the accuracy of the algorithm. The simulated and measured results show that the cylindrical conformal phased array can achieve 3D-MIMO beam coverage from 0° to 360° in the azimuth plane and from 67.5° to 112.5° in the elevation plane. It can be applied for satellite communication and fifth-generation base station communication.

Local Search algorithm for two-stage problem of radio communication systems planning

The development of the Arctic territories is one of the priority strategies of the Russian Federation. In this regard, there is a large number of questions in various areas that need to be discussed. The article deals with the problem of improving radio communication in the region. One of the problems related to the location of communication stations is formulated. Its mathematical model is constructed, approximation algorithms of its decision are proposed, the first results of numerical experiments are discussed.

Exploring sociodemographic subgroup differences in multiple mini-interview (MMI) performance based on MMI station type and the implications for the predictive fairness of the Hamburg MMI

BackgroundSociodemographic subgroup differences in multiple mini-interview (MMI) performance have been extensively studied within the MMI research literature, but heterogeneous findings demand a closer look at how specific aspects of MMI design (such as station type) affect these differences. So far, it has not been investigated whether sociodemographic subgroup differences imply that an MMI is biased, particularly in terms of its predictive validity.MethodsBetween 2010 and 2017, the University Medical Centre Hamburg-Eppendorf (UKE) tested 1438 candidates in an MMI who also provided sociodemographic data and agreed to participate in this study. Out of these, 400 candidates were admitted and underwent a first objective structured clinical examination (OSCE) after one and a half years, including one station assessing communication skills. First, we analyzed the relationship between gender, age, native language and medical family background and MMI station performance including interaction terms with MMI station type (simulation, interview, and group) in a hierarchical linear model. Second, we tested whether the prediction of OSCE overall and communication station performance in particular differed depending on sociodemographic background by adding interaction terms between MMI performance and gender, age and medical family background in a linear regression model.ResultsYoung female candidates performed better than young male candidates both at interview and simulation stations. The gender difference was smaller (simulation) or non-significant (interview) in older candidates. There were no gender or age effects in MMI group station performance. All effects were very small, with the overall model explaining only 0.6% of the variance. MMI performance was not related to OSCE overall performance but significantly predicted OSCE communication station performance with no differences in the prediction for sociodemographic subgroups.ConclusionsThe Hamburg MMI is fair in its prediction of OSCE communication scores. Differences in MMI station performance for gender and age and their interaction with MMI station type can be related to the dimensions assessed at different station types and thus support the validity of the MMI. Rather than being threats to fairness, these differences could be useful for decisions relating to the design and use of an MMI.

Current Problems of Improving the Coordinate-Time Support of GLONASS and Promising Methods for Their Solution. 1. Alignment of Coordinate Systems Used by Various Information Technologies to Refine the Geocenter’s Position

The article considers the problem of improving the coordinate-time support of GLONASS, which implies refining the models of a wide range of stochastic error components caused by inaccurate knowledge of geodetic and geodynamic parameters, such as the position and displacement rate of the geocenter, Universal Time, pole shift, irregularities of the Earth’s rotation, precession, and nutation. It is shown that the problem can be solved only using a comprehensive measurement technique that includes the use of various information measurement “techniques,” namely, global navigation satellite systems, quantum-optical communication stations, Doppler velocity sensors, and very-long-baseline radio interferometers. The problem of aligning coordinate systems on which the application of a particular information technology is based that arises from using this approach is discussed. Mathematical models, algorithms, and the results of their development in the experiments on the alignment of coordinate systems used in global navigation satellite systems and quantum-optical communication stations are given. The presented results contain estimates of the misalignment between different coordinate systems, including misalignment by center position and misalignment due to difference in the scale factor and orientation with respect to the inertial coordinate system.

Tropospheric Effect on the Transmissivity of the Spacecraft–Ground Tracking Station Communication Line

Algorithms ensuring high-speed and reliable data transmission under lognormal amplitude fluctuations (described by Fraunhofer diffraction) in the spacecraft–ground tracking station line for coherent and incoherent reception of signals have been considered. An advantage of the coherent reception of millimeter-range signals with a random error-correcting code has been indicated.

The Standardization Design and Implementation of Voice Communication System of Large Enterprise Group

Communication means each order the necessary analysis of nuclear power plant, a stage through side regret, for nuclear power and multi pass liquid, means integration for more business, the cost of safety and convenience of system test, with the help of the multi Taiwan card speed to introduce multi communication system integration to solve the purple construction requirements and fusion methods, combined with the nuclear power plant on the point, from the value node angle in operation and operation in order dispatch station communication means fusion provides a new way with words hung off wrinkles.

Research on Nuclear Power Project Communication

With the development and progress of electric power industry, the demand for communication is more and more, this paper introduces the specific functions of each subsystem in the field communication system of nuclear power station of Technology, and discusses the application of each subsystem in nuclear power from the angle of field use demand. Through the detailed introduction of this article, let people deeply understand the Nuclear Power Station Communication System.