Current Communication Systems Research Articles

Computer‐aided experimental studies for adaptive beamforming algorithms and array processing in engineering education

AbstractSmart antenna and digital antenna systems are considered as a crucial technology for current and future communication systems supporting 5G/6G and nonterrestrial‐networks communications. Based on the information of the received signal/s, smart antenna systems toward the radiation pattern to the desired direction/s. This technique is known as adaptive beamforming. The theories and the applications of adaptive beamforming are taught in engineering educational courses. This paper proposes a set of real‐time interactive experiments for adaptive beamforming algorithms in antenna array processing subject. The proposed experiments can be performed with the computer‐aided experimental studies tool prepared in the MATLAB® environment. The users can easily make comparisons and can perform trade‐offs between different types of adaptive beamforming algorithms, scenarios, and antenna architecture. This is used as a teaching tool for a graduate course on adaptive beamforming algorithms.

Enhancing Data Protection through Advanced Encryption or Improving Data Security with Advanced Encryption

The protection of information content is becoming a key concern with the recent exponential growth of digital data interchange over computer networks. Numerous security vulnerabilities can readily jeopardize the information sent over a network. An enhanced modification for the Advanced Encryption Standard (AES) algorithm is proposed and implemented using an additional key that generated using a linear feedback shift register (LFSR), which provides an efficient technique to pseudo random number generation and also reduces the number of rounds. Cryptography plays a crucial role in ensuring the security of digital data transmission over these unsafe networks. When compared to the original AES algorithm result, the suggested technique produces the expected results for several data types, including text, images, It is more important than ever to strengthen data protection procedures in an era of rising cyber dangers and growing reliance on digital data. A thorough framework for "Enhancing Data Protection through Advanced Encryption" (EDPAE) is introduced in this study. The project's goal is to protect sensitive data by utilizing state-of-the-art encryption techniques in response to the ever-changing cyber security scenario. In addition, the project places a strong emphasis on how to seamlessly incorporate advanced encryption into current data storage and communication systems in order to minimize interference with user operations and greatly improve overall security posture. In order to guarantee the secure creation, distribution, and storage of encryption keys and to reduce potential risks related to key compromise, key management features are addressed.

A broadband transparent antenna applied in indoor mobile communication system

AbstractThis paper proposes a broadband optical transparent antenna using a transparent conductor film on a transparent polyethylene terephthalate (PET) substrate. The planar wide‐slot antenna coupling fed by microstrip has a wide impedance bandwidth, so it is selected to design the transparent antenna. The upper surface of the PET substrate is a microstrip line with a fork‐shaped tuning branch, and the lower surface is a wide slot. They were made of transparent conductor film. Finally, a new capacitive coupling method is used to feed the transparent antenna. The transparent conductor film used in the antenna is metal mesh, which was developed by 3M company. The metal mesh with an open area greater than 80% to achieve high transmittance. The measured results show that the impedance bandwidth is 177% (0.30–5.0 GHz), and the gain of the antenna varies from 5.06 to 7.8 dBi over the entire frequency band. Therefore, it can be well applied to the current indoor mobile communication system.

Introduction of a bleepless intern on-call era

BackgroundThe current bleep communication system between nurses and interns on-call in most Irish hospitals has been linked with interruption in patient care, disruption to workflow, inefficiency, increased burden and stress to the on-call health staff. A new electronic system was introduced in a University Hospital to replace and eliminate bleep usage during on-call hours. MethodsAn Intern on-call task electronic template was generated using Microsoft Excel Spreadsheet. This electronic system enabled users to review and respond to requests placed by nursing healthcare staff. This project initially underwent a trial process in three wards for a period of two weeks in June 2023. Interns and nurses were asked to fill a survey before and after introduction of the system. The project was implemented across all wards in August 2023 and a secondary survey was obtained. In addition, the spreadsheets were analysed retrospectively. ResultsDuring the trial, twenty-six interns and twenty nurses were surveyed before and after implementation of the electronic system. Interns satisfaction rate was 73% and stress was reported to be reduced by 65%. Notably, 57% of interns reported a reduction in workload and the number of bleeps was reported to be as <10 by 42%. Nurses reported a decrease in the number of bleeps they needed to send overall by 65% and by 55% for repeated jobs. Workload was reported to be increased by 15% by nurses. However, exactly half of the nurses were unhappy with the new system and stress levels were unchanged. ConclusionThis project has shown promising results, efficient and clear communication was noted with an overall positive feedback and satisfaction rate by doctors. However, as evident, from a nursing perspective further work is needed to further progress into a system that can benefit both parties involved.

Miniaturized Lens Antenna with Enhanced Gain and Dual-Focusing for Millimeter-Wave Radar System.

This paper presents a waveguide Lens antenna at the W-band adopting dual-focusing Lens to improve the performance. The Lens antenna consisted of a waveguide slotted structure and lenses processed using NOA73 meet the demands of miniaturization for current communication systems. The antenna radome fabricated using NOA73 not only protects the antenna structure but also improves the gain of the antenna by about 9.5 dBi via electromagnetic wave dual-focusing. A prototype is fabricated using novel UV-LIGA technology. Measured results are compared with simulated values. Measured results confirmed the fabricated antenna operated in the W-band with a 10 dB fractional bandwidth (FBW) of 6.5% from 97.5 to 104 GHz and a peak gain of 22 dBi at 100 GHz in the direction perpendicular to the plane of the feed waveguide. A good agreement between simulation and measurement is obtained, demonstrating efficient radiations in the operating band.

A Novel Wideband Splitter for a Four-Element Antenna Array

In the paper, a novel design of a wideband power splitter for a four-element antenna array using two RF antiphase segments is proposed. Based on a detailed analysis of the power splitter circuit, an analytical model was set up in the MATLAB environment. The derived analytical model allows the development of a design of the described structure for any operating frequency and estimates the properties of the designed structure. In addition to the RF electrical part, the copper cover is also considered in this study. The copper cover serves as both a support and shielding part of the proposed structure. The electrical part consists of two sections of transmission lines. The first transmission line is symmetrical, while the second transmission line is asymmetrical. The given transmission lines can be realized using any technology (microstrip, coaxial, etc.). A prototype of the proposed wideband splitter operating at 650 MHz with a fractional bandwidth of 84.3% was designed and tested in real-world conditions to prove the concept. The board of the manufactured prototype has dimensions of 25 × 152 mm. A double-sided FR4 material with a substrate height of 1.48 mm, copper thickness of 50μm, and ϵr ≅ 4.3, with a dielectric loss tangent of 0.021 was used to manufacture the prototype. The prototype was tested and its parameters were verified in practical conditions as a part of the current radio communication system for the 5G band. Under these conditions, verification measurements of the proposed splitter with a four-element antenna array were carried out.

A Review of Over-the-Air Testing Methods for Performance Measurement of Antennas and Devices in Communication Systems

With the fast development of communication techniques, over-the-air testing has developed into the main testing method for current communication systems due to its advantages including no cable connection, high measurement efficiency, and independence from environment. OTA testing has become almost the only solution for 5G system testing especially after the popularity of 5G massive multiple-input-multiple-output. In this paper, we summarize the three main methods of OTA testing including the reverberation chamber-based method, the radiation two-step method, and the multiprobe anechoic chamber- (MPAC-) based method, among which we focus on the MPAC method systematically. In the MPAC method, there are two main channel synthesis techniques that have been heavily studied, namely, prefaded signal synthesis and plane wave synthesis. We summarize the current main research based on these two techniques including probe configurations, probe selection algorithms, and probe design based on the PFS technique and the design of plane wave generators based on PWS technique. The main comparisons are made for the performance of different probe selection algorithms and the performance of different plane wave generators as well as the latest advances.

High-speed data transmission based on mode-locked optical frequency comb

&lt;sec&gt;With the rapid development of emerging technologies such as multimedia services, live broadcasting, video conferencing, and high-definition television, traditional radio frequency communication is unable to meet people 's growing demand for communication capacity and transmission rate. In recent years, optical communication has received extensive attention from the industrial and scientific communities due to its advantages of large bandwidth, high speed, low power consumption, light weight, and strong anti-interference ability. As an emerging light source, the optical frequency comb (OFC) has a wide spectral range, multi-wavelength, high stability, and good phase coherence, providing a new idea for studying microwave signals with simple system structure, strong tunability and high frequency stability. At the same time, the multi-optical mode characteristics of OFC are compatible with the current communication system based on wavelength division multiplexing technology. Hundreds of laser arrays in a traditional communication system can be replaced by only one laser, which greatly reduces the power consumption of the system.&lt;/sec&gt;&lt;sec&gt;Combining the above advantages, in this paper, a large-scale parallel high-speed optical communication system based on mode-locked OFC is proposed. The linewidth of the OFC locked to the rubidium atomic clock can reach 1 Hz, which is sufficient to support the transmission of high-order modulation signals. The electro-optic modulators are used to adjust the amplitude and phase of each optical mode of the mode-locked OFC and self-coherently map to the RF domain. The high-speed high-order modulation signal with coded information is obtained by frequency screening through a narrow-band filter. The communication capability of the microwave photonic modulation signal in the 16 quadrature amplitude modulation (QAM) format is verified by simulation. The 16QAM communication with the rate of 2, 6, and 14 Gbit/s is realized by using the photonic microwave signal on the 100 m space optical link, and the bit error rate (BER) is less than 10&lt;sup&gt;–6&lt;/sup&gt;. The proposed large-scale parallel optical communication system based on mode-locked OFC can achieve high-speed information transmission with a compact system structure, which is suitable for inter-satellite communication, emergency communication, military communication and other fields.&lt;/sec&gt;

Optimized Design of an Ultrasonic-Based High-Efficiency Wireless Passive Monitoring System for Sealed Metal Compartments.

The condition monitoring (CM) of sealed metal compartments (SMCs) is an urgently required restructure. Ultrasound penetrates SMCs to power and communicate with built-in sensors, enabling the CM of SMCs. However, current ultrasonic wireless power transfer and data communication (UWPTADC) systems are large and complex, and limited by the efficiency of energy transfer and data reliability. In this paper, an optimized design of a high-efficiency wireless passive monitoring system using UWPTADC techniques is proposed for SMC. The circuit model of the system is developed and analyzed to achieve an optimal design for efficient wireless power transfer and effective data communication coupling. A test system was constructed using a steel wall of 11 mm thickness as a validation object. At the ultrasonic carrier frequency of 1.045 MHz, the system has an energy transfer efficiency of 60%, and a communication rate of 50 kbps. In addition, the system realizes temperature and humidity monitoring inside a 13 mm thick cylindrical SMC, simulating the process of ultrasonic CM of an actual engine compartment. The system provides a wiring-free and battery-free solution for CM in SMCs, advancing CM in aerospace, marine and other fields.

Novel Optical Kerr Switching Photonic Device Based on Nonlinear Carbon Material.

In the context of current communication systems, there is an urgent demand for more efficient and higher-speed optical signal processing technologies. Researchers are actively exploring new materials and devices to harness nonlinear optical phenomena, seeking advancements in this field. Nonlinear carbon materials, especially promising 2D materials, have garnered attention for their potential interaction with light and have become integral to the development of all-optical signal processing devices. This study focuses on utilizing a photonic device based on a nonlinear Au/CB composite material for optical Kerr switching. The application of Au/CB as a nonlinear material in the Kerr switch represents a noteworthy advancement, demonstrating its capability to modulate optical signals. By appropriately applying a pump light, the study achieves optical Kerr switching with an extinction ratio of approximately 15 dB in the fully off state of the signal light carrying a 10 GHz analog signal, marking a pioneering achievement in the field to the best of our knowledge. The experimental results, encompassing extinction ratios, signal control, and stability, not only validate the feasibility of this technology but also underscore its potential applicability within optical communication systems. The successful modulation and control of a 10 GHz analog signal showcase the practicality and effectiveness of the Au/CB-based optical Kerr switch. This progress contributes to the continuous evolution of optical Kerr switching, a crucial component in modern optical communication systems. Therefore, we believe that the Au/CB-based optical Kerr switch is an exceptionally promising and stable all-optical signal processing device. As the contemporary communication landscape evolves, the integration of this technology holds the potential to enhance the efficiency and speed of optical signal processing.

Frequency-reconfigurable variode enabled metasurface reflector loaded antenna

A compact high gain frequency reconfigurable metasurface reflector (MSR) loaded antenna using a varactor diode is proposed in this paper. In comparison to a traditional antenna, a metamaterial (MTM) loaded with CSRR is used to achieve a size reduction up to 70%. The ground plane of the proposed slotted decagon antenna has been loaded with a complementary split-ring resonator (CSRR). With dimensions of 0.24 λ × 0.24 λ × 0.013 λ (λ represents the center frequency at 2.40 GHz) the antenna is extremely compact. The antenna is designed on an FR4 substrate with εr = 4.4 & 1.6 mm of thickness. The investigation shows that utilization of the MSR structure has significantly increased gain compared to the decagon antenna without MSR. The MSR-loaded antenna dimension is 0.48 λ × 0.47λ × 0.013 λ (λ represents the center frequency at 2.40 GHz). Frequency reconfigurability is introduced by placing a varactor diode on the patch’s upper side. Changing the varactor’s DC reverse bias voltage from 0 to 10 V causes its resonance frequency to shift from 2420 to 2550 MHz, giving it a tuning ratio of 1.35. The proposed antenna offers efficiency ranges from 70%–80% over the operating bands. Except for a small deviation, there is a fair match between measured and simulated values. The antenna can be used in a variety of current and future communication systems.

Review on filtering antenna technology for 5G mobile system

In recent years, people’s increased demand for wireless communication technology fuels the development of 5G communication technology growth. Electronic equipment in the current wireless communication system is developing in the direction of low power consumption, multi-function, miniaturization, and integration, which also puts higher technical standards for RF front-end. In recent years, the wireless communication industry is building lighter, thinner, and smaller products with multifunction. The integration of filter and antenna is one of the important ways for the miniaturization of electronic systems. The antenna and filter are integrated to form a filtering antenna, which can effectively reduce the size and weight of the RF front end while realizing the function of radiation and filtering. This paper first introduces the research background and significance of this topic according to the background of mobile communication technology, and the main challenges faced by 5G communication. Then, the working principle of filtering antenna and multiple-input multiple-output technology (MIMO) are introduced, and finally the development and research status of 5G filtering antenna are summarized, and some relevant personal views are put forward.

Assessment of Security KPIs for 5G Network Slices for Special Groups of Subscribers

It is clear that 5G networks have already become integral to our present. However, a significant issue lies in the fact that current 5G communication systems are incapable of fully ensuring the required quality of service and the security of transmitted data, especially in government networks that operate in the context of the Internet of Things, hostilities, hybrid warfare, and cyberwarfare. The use of 5G extends to critical infrastructure operators and special users such as law enforcement, governments, and the military. Adapting modern cellular networks to meet the specific needs of these special users is not only feasible but also necessary. In doing so, these networks must meet additional stringent requirements for reliability, performance, and, most importantly, data security. This scientific paper is dedicated to addressing the challenges associated with ensuring cybersecurity in this context. To effectively improve or ensure a sufficient level of cybersecurity, it is essential to measure the primary indicators of the effectiveness of the security system. At the moment, there are no comprehensive lists of these key indicators that require priority monitoring. Therefore, this article first analyzed the existing similar indicators and presented a list of them, which will make it possible to continuously monitor the state of cybersecurity systems of 5G cellular networks with the aim of using them for groups of special users. Based on this list of cybersecurity KPIs, as a result, this article presents a model to identify and evaluate these indicators. To develop this model, we comprehensively analyzed potential groups of performance indicators, selected the most relevant ones, and introduced a mathematical framework for their quantitative assessment. Furthermore, as part of our research efforts, we proposed enhancements to the core of the 4G/5G network. These enhancements enable data collection and statistical analysis through specialized sensors and existing servers, contributing to improved cybersecurity within these networks. Thus, the approach proposed in the article opens up an opportunity for continuous monitoring and, accordingly, improving the performance indicators of cybersecurity systems, which in turn makes it possible to use them for the maintenance of critical infrastructure and other users whose service presents increased requirements for cybersecurity systems.

Design analysis and optimization of chaotic systems for duration and carrier parallel index modulation

With the rapid advancement in communication technology, the demand for high speed and efficient transmission has increased significantly. Traditional communication systems are unable to meet these demands, and thus, this paper proposes a new correlated delay shift keying system for duration and carrier parallel index modulation (DCIM-CDSK) that employs duration and carrier parallel index modulation. The DCIM-CDSK system utilizes index mapping to transmit extra bits, while group mapping the timeslots on the carrier. By using spare timeslots in each group to transmit modulated information bits, the system achieves high-speed transmission with high efficiency. Additionally, the system introduces a noise reduction method to optimize the information-carrying signal to improve its noise immunity. The theoretical bit error rate (BER) equations is derived in the paper for the DCIM-CDSK system under Gaussian and Rayleigh fading channels, and compared them with practical simulations to validate the theoretical derivation. The paper also analyzes the BER of the system for a single longest timeslot length and mixed longest timeslot length, respectively. The simulation results show that the proposed DCIM-CDSK system has better noise immunity and higher transmission rates than other similar systems. In today's increasingly stringent requirements for communication systems, the DCIM-CDSK system, with its high spectral and energy efficiency, provides a feasible solution for the current communication system industry to realize large user group services and high bandwidth utilization efficiency. At the same time, because of the flexibility of the system between the transmission rate and BER performance, the communication system can get a better trade-off and balance between the two contradictions of effectiveness and reliability.

RIS-aided dynamically adaptive wide field-of-view receiver for visible light communication in industrial internet of things.

In the current visible light communication (VLC) system, a condenser lens is generally used in the front of receiver to achieve a higher data rate, making an extremely narrow field-of-view for the receiver. With the spread of Industrial Internet of Things (IIoT), the communication between mobile terminals is urgently required. A wide-range detecting method for VLC system in IIoT scenario is asked. In this paper, a novel self-adaptive wide-FoV receiver involving reconfigurable intelligent surfaces (RIS) is proposed. The effective detecting range of the receiver can be expanded by dynamically adjusting the incident light directions with the assistance of RIS. Based on the maximum arrived flux criterion, the mathematical model is established and the optimized RIS parameter tuning algorithm is presented. The feasibility and validity of the method are verified by simulation. The results show that the tolerable transceiver offset can be increased to 2∼4 times as the conventional receiver.

Design and analysis of frequency reconfigurable antenna in S-band

One of the biggest challenges in modern communication systems is to provide a single antenna for multiple applications. Existing antenna systems are limited to some applications. Therefore, it is important to design a single reconfigurable antenna for multiple applications in current communication systems. To overcome this problem, a single antenna with frequency reconfiguration capability has been developed in this work. In this work, four different frequency reconfigurable antenna layouts are investigated. To provide frequency reconfigurability, the proposed antenna comprises two P-intrinsic-N (PIN) diodes placed between the microstrip line and patch. The antenna can resonate in four states and operate at three distinct frequencies without affecting the size of the antenna by toggling the 'ON' and 'OFF' modes of the PIN diodes. The antenna can operate at three different frequency ranges, depending on the switching state of the PIN diode 2.1, 2.4 and 3.0 GHz. The voltage standing wave ratio (VSWR), gain, return loss (RL) and radiation patterns of the antennas were simulated and measured. It is clear that the proposed antenna works at different operating frequencies. The gain and RL for the corresponding frequencies are significantly improved and the radiation pattern is symmetrical.

Delay/Disruption-Tolerant Networking-based the Integrated Deep-Space Relay Network: State-of-the-Art

Communication with deep-space elements poses significant challenges due to vast distances, orbital motions, and harsh environmental conditions that restrict point-to-point or end-to-end communication. Disruption/Delay-Tolerant Networking (DTNs) is a special kind of computer network architecture, that overcomes the shortcomings of the TCP/IP suite in meeting deep-space networking requirements with intermittent end-to-end connectivity. In DTN, data transmission follows a store-carry-forward approach, where bundles (data) are transferred as custody between relay nodes. This necessitates more complex routing strategies involving additional route computations and network resource consumption but provides greater flexibility for unstable connectivity. This study is an updated literature review in the context of DTN-based deep-space communication. It covers the recent studies that address the architecture of current and future deep-space communication systems, the environmental challenges of deep-space communication, various implementations and demonstrations of DTN's architecture, and the validation of its related routing strategies over the Deep Space Relay network. Additionally, this review explores the integration of machine learning techniques into DTN routing strategies, along with ongoing research directions and open issues in DTN-based DSN. Examining the state-of-the-art literature reveals that developing an intelligent unified n-copy-based forwarding routing scheme holds promise for effectively integrating into deep space communications and achieving optimal networking among the diverse segments of the future unified Interplanetary Internet.

Depth from motion parallax: Deictic consistency, eye contact, and a serious problem with Zoom.

The dynamics of head and eye gaze between two or more individuals displayed during verbal and nonverbal face-to-face communication contains a wealth of information and is used for both volitionary and unconscious signaling. Current video communication systems convey visual signals about gaze behavior and other directional cues, but the information they carry is often spurious and potentially misleading. I discuss the consequences of this situation, identify the source of the problem as a more general lack of deictic consistency, and demonstrate that using display technologies that simulate motion parallax are both necessary and sufficient to alleviate it. I then devise an avatar-based remote communication solution that achieves deictic consistency and provides natural, dynamic eye contact for computer-mediated audiovisual communication.

A novel approach for screening standard anteroposterior pelvic radiographs in children.

The artificial intelligence-assisted method was more efficient and highly consistent with clinical experts. This method can be used for real-time validation of the quality of pelvic radiographs in current picture archiving and communications systems (PACS). • Nonstandard pediatric radiographs with pelvic malposition make the correct diagnosis of developmental dysplasia of the hip (DDH) challenging. • Traditional manual assessment remains the only method available for screening standard pediatric pelvic radiographs, which is relatively laborious and potentially erroneous. • This study proposed an artificial intelligence-assisted model to assess the quality of pediatric pelvic radiographs accurately and efficiently. • We recommend the integration of the model into current picture archiving and communications systems (PACS) for real-time screening of standard pediatric pelvic radiographs.

Utilizing Solar Power for Communication and Illumination in Disaster Zones

Abstract Natural disasters often occur on this earth, especially in Indonesia. There are several types of disasters that occur, namely: geological disasters, hydrometeorological disasters and others. This natural disaster caused quite a lot of casualties and not a few material. Good post-natural disaster management is necessary to minimize the number of victims of a disaster. One form of handling this natural disaster is by providing electrical energy that can be used to provide lighting and communication systems. The provision of electrical energy consists of several integrated systems to form a compact, simple and efficient unit. This tool consists of a Solar Power Generation system, GenSet system, inverter system, Change Over Switch system and Global Positioning System system. This tool is named SUNPO which stands for Sun Power or Solar Power. With this SUNPO, it can function as a power supply to power direct current loads and alternating current loads. If the solar power is not enough to charge the battery then the system can be operated with a GenSet. Meanwhile, to find out the position of SUNPO, a Global Positioning System is also installed.&#x0D; Highlights:&#x0D; &#x0D; &#x0D; Effective Disaster Response: Efficient post-disaster management is crucial to minimize casualties and damage caused by natural disasters, especially in Indonesia.&#x0D; &#x0D; &#x0D; SUNPO Tool Integration: The SUNPO (Sun Power) tool integrates solar power generation, GenSet backup, inverter, changeover switch, and GPS systems to provide a reliable and compact solution for electricity supply in disaster-stricken areas.&#x0D; &#x0D; &#x0D; Dual Power Source: SUNPO offers dual power sources - solar energy and GenSet - ensuring continuous electricity supply for both direct and alternating current loads, enhancing communication and lighting systems for affected communities.&#x0D; &#x0D; &#x0D; Keywords: Natural disasters, Post-disaster management, SUNPO, Solar Power, Global Positioning System.