Transmission Speed Research Articles

Warunki koegzystencji ludzi z infrastrukturą elektromagnetycznych technologii radiokomunikacyjnych w wybranych mikrośrodowiskach

This is a study of how people coexisting with the infrastructure of electromagnetic mobile communication technologies emitting radio waves in the work and living environment: (i) in passenger trains, (ii) in shopping centres and (iii) in passenger cars. It revealed significantly different trends, over the last five years (2018-2023), in the structure of exposure to radio waves, with slight changes in the level of total exposure in analysed environments used by workers and the public. The observed changes are related to the spread of mobile access to fast data transfer and increased speed of transmission from personal devices (terminals such as smartphones or tablets). The results from shopping centres showed dominant downlink-components of exposure (from base stations) and a broadening of their frequency band (due to the spread of LTE subscription services using the 2100 and 2600 MHz bands) in 2023, along with reduced uplink-components (from terminals) and components related to local hotspots of non-subscription networks (Wi-Fi). A broadening of the frequency band was also observed in measurements from passenger trains, but with the dominant uplink-components of exposure, regardless of the availability of local hotspots. In passenger cars, exposure to external radio waves (downlink components) also broadened in the frequency band (in the LTE 800 and 2600 MHz bands). A reduction in exposure fluctuations over time was found in all the studied microenvironments. This implies that different measures are necessary to reduce workers’ exposure, along with different methods of identifying and assessing the parameters there.

Nitrogen-Doped CoP with optimized d-Band center as bidirectional electrocatalyst for high areal capacity of Li-S battery

Lithium polysulfide (LiPSs) shuttle effect and difficulties with Li2S oxidation are hinder the marketization of lithium-sulfur batteries. We suggest using a bidirectional catalyst in the sulfur host to solve these problems. We produced a nitrogen-doped cobalt phosphide (N-CoP@NC) as a sulfur carrier in this work. The introduction of nitrogen into cobalt phosphide enhances the electron transmission speed and forms shorter Co-N bonds. As a result, new defect energy levels are introduced, leading to an increase in the charge number of Co central atoms, which abate the Li-S and SS bonds in Li2S and Li2S4, thereby promoting the oxidation of Li2S during charging, as well as the alteration process of LiPSs during charge and discharge. Additionally, the crystal flaws that result in increased Co-S bond formation help to boost polysulfides' adsorption ability. The Li-S batteries shows outstanding cyclability when paired with this electrocatalyst, demonstrating a minimal capacity degradation rate of only 0.07 % per cycle over 500 cycles at a rate of 0.5C. As a result, incorporating anion doping in the host emerges as a promising method for crafting materials tailored for Li-S batteries.

Light transmission speed of different hybrid pump cascade structures in Er3+ doped fiber

In this paper, the general theory of generating fast light and slow light in erbium-doped fiber by hybrid pump cascade structure based on coherent population oscillation effect is given. Through numerical simulation, the effects of pump optical power ratio ([Formula: see text]) on gain, group-induced refractive index [Formula: see text], time delay and fractional delay of pumping structure (1480 and 980[Formula: see text]nm) and pumping structure (980 and 1480[Formula: see text]nm) are studied and analyzed. The effects of pumping structure and pumping direction on time delay, fractional delay and fast/slow light conversion are discussed. In addition, the effects of different pump optical power ratios ([Formula: see text]) on time delay and fractional delay are also discussed. Compared with previous methods such as changing the interaction length and doping ion density, a more suitable optical transmission speed can be obtained by adjusting pump composition, pump direction and pump ratio ([Formula: see text]). This may lead to the optimization of optical communication systems.

The Practical Research on the Red Film and Television Culture Helping the Ideological Education of College Students

Film and television culture has been favored by college students for its artistic comprehensiveness, rapid transmission speed, large amount of information, simple way, wide radiation range and market-oriented content. The values it spreads have a subtle influence on the ideological and political orientation of young students and the quality of college cultural education. This paper tries to study the influence and practical path of red film and television culture on the value orientation of contemporary college students from the perspective of socialist core values.

Optimized Two-Tier Caching with Hybrid Millimeter-Wave and Microwave Communications for 6G Networks

Data caching is a promising technique to alleviate the data traffic burden from the backhaul and minimize data access delay. However, the cache capacity constraint poses a significant challenge to obtaining content through the cache resource that degrades the caching performance. In this paper, we propose a novel two-tier caching mechanism for data caching on mobile user equipment (UE) and the small base station (SBS) level in ultra-dense 6G heterogeneous networks for reducing data access failure via cache resources. The two-tier caching enables users to retrieve their desired content from cache resources through device-to-device (D2D) communications from neighboring users or the serving SBS. The cache-enabled UE exploits millimeter-wave (mmWave)-based D2D communications, utilizing line-of-sight (LoS) links for high-speed data transmission to content-demanding mobile UE within a limited connection time. In the event of D2D communication failures, a dual-mode hybrid system, combining mmWave and microwave μWave technologies, is utilized to ensure effective data transmission between the SBS and UE to fulfill users’ data demands. In the proposed framework. the data transmission speed is optimized through mmWave signals in line-of-sight (LoS) conditions. In non-LoS scenarios, the system switches to μWave mode for obstacle-penetrating signal transmission. Subsequently, we propose a reinforcement learning (RL) approach to optimize cache decisions through the approximation of the Q action-value function. The proposed technique undergoes iterative learning, adapting to dynamic network conditions to enhance the content placement policy and minimize delay. Extensive simulations demonstrate the efficiency of our proposed approach in significantly reducing network delay compared with benchmark schemes.

The application of the internet of things technology in the smart grid

The development of electric power and the energy industry is an important guarantee for national economic development. With the explosion of population and the development of science and technology, the power system needs to be more intelligent and networked to facilitate management and optimization. In recent years, the Internet of Things (IoT) technology has continued to develop through the combination of Internet technology and sensor technology, and the fast network transmission speed as well as the miniaturization and refinement of sensing can help the construction of the smart grid. This paper analyzes the application of IoT technology in the smart grid, including different types of smart grid architecture and the practical application of the IoT technology in the whole process of power transmission. Besides, the paper also discusses different application links and network levels. At present, the IoT technology has been applied to the smart grid information collection, transmission, and processing process, participating in information management in the power station, power transmission, substation, and other links. However, due to the complexity of processing the massive data of the power grid and the multiple network connections during the transmission process, ensuring the security of information and networks has become a challenge. While realizing high-speed communication, it is necessary to ensure the security of users as well as the information communication and networks.

Design of High-Gain Antenna Arrays for Terahertz Applications.

A terahertz band (0.1-10 THz) has the characteristics of rich spectrum resources, high transmission speed, strong penetration, and clear directionality. However, the terahertz signal will suffer serious attenuation and absorption during transmission. Therefore, a terahertz antenna with high gain, high efficiency, and wide bandwidth is an indispensable key component of terahertz wireless systems and has become a research hotspot in the field of antennas. In this paper, a high-gain broadband antenna is presented for terahertz applications. The antenna is a three-layer structure, fed by a grounded coplanar waveguide (GCPW), using polytetrafluoroethylene (PTFE) material as the dielectric substrate, and the metal through-hole of the dielectric substrate forms a substrate-integrated waveguide (SIW) structure. The metal fence structure is introduced to reduce the coupling effect between the radiation patches and increase the radiation bandwidth and gain. The center frequency is 0.6366 THz, the operating bandwidth is 0.61-0.68 THz, the minimum value of the voltage standing wave ratio (VSWR) is 1.00158, and the peak gain is 13.14 dBi. In addition, the performance of the designed antenna with a different isolation structure, the length of the connection line, the height of the substrate, the radius of the through-hole, and the thickness of the patch is also studied.

A library of electrophysiological responses in plants - a model of transversal education and open science

ABSTRACT Electrophysiology in plants is understudied, and, moreover, an ideal model for student inclusion at all levels of education. Here, we report on an investigation in open science, whereby scientists worked with high school students, faculty, and undergraduates from Chile, Germany, Serbia, South Korea, and the USA. The students recorded the electrophysiological signals of >15 plant species in response to a flame or tactile stimulus applied to the leaves. We observed that approximately 60% of the plants studied showed an electrophysiological response, with a delay of ~ 3-6 s after stimulus presentation. In preliminary conduction velocity experiments, we verified that observed signals are indeed biological in origin, with information transmission speeds of ~ 2–9 mm/s. Such easily replicable experiments can serve to include more investigators and students in contributing to our understanding of plant electrophysiology.

A Systematic Review on Non-Orthogonal Multiple Access (NOMA) Based on Visible Light Communication for Intelligent Transportation Systems

Non-Orthogonal Multiple Access (NOMA) is a cutting-edge technology that permits several users to use the same frequency resources and transfer data at once. Visible light communication also known as VLC, is an innovative technology that offers access to an unoccupied spectrum, enables fast data transmission speeds, thereby making it a complementary addition to current radio frequency technology. Although VLC has its advantages, it also comes with some downsides. One major issue is the modulation bandwidth of LEDs, which can be quite challenging when creating high speed VLC systems. Non-orthogonal multiple access (NOMA), particularly power-domain NOMA (PD-NOMA), has become a viable multiple access approach, ensuring sufficient bandwidth allocation for VLC systems. This study delves into multiple access techniques in VLC systems, in particular NOMA, and discusses its fundamental principles, key ideas and practical implementations like vehicular communication. It also addresses the associated hurdles, such as ensuring equitable distribution of optical power among users, leveraging MIMO technology, and grappling with LED nonlinearity issues. In summary, we underscore the significance of utilizing NOMA-VLC technology to enhance wireless communication systems and optimize spectral efficiency.

The application of Internet of Things technology in intelligent fire protection

The uncertainty of fire and the difficulty of accurate prevention greatly increase the difficulty of fire prevention and control. Therefore, it is necessary to actively introduce modern science and technology, adopt fire Internet of Things (IoT) technology, realize remote dynamic monitoring, and accurately obtain fire prevention and control data information. This paper carries out an in-depth analysis on fire prevention and control, focusing on the application of fire IoT in the field of fire prevention and control. In addition, it specifically introduces the key technologies of intelligent fire protection, Radio Frequency ID, and the construction of fire safety models. At the same time, it describes the problems faced by the IoT in intelligent fire protection, that is, the quality of transmitted information is not strong, the speed of message transmission needs to be improved, and the application platform that is more conducive to the transmission of information needs to be built. By overcoming these issues, the future intelligent fire control system will be more intelligent and bring more convenience to people.

COVID-19: An overview on possible transmission ways, sampling matrices and diagnosis.

COVID-19 is an RNA virus belonging to the SARS family of viruses and includes a wide range of symptoms along with effects on other body organs in addition to the respiratory system. The high speed of transmission, severe complications, and high death rate caused scientists to focus on this disease. Today, many different investigation types are performed on COVID-19 from various points of view in the literature. This review summarizes most of them to provide a useful guideline for researchers in this field. After a general introduction, this review is divided into three parts. In the first one, various transmission ways COVID-19 are classified and explained in detail. The second part reviews the used biological samples for the detection of virus and the final section describes the various methods reported for the diagnosis of COVID-19 in various biological matrices.

Dynamics of neural fields with exponential temporal kernel.

We consider the standard neural field equation with an exponential temporal kernel. We analyze the time-independent (static) and time-dependent (dynamic) bifurcations of the equilibrium solution and the emerging spatiotemporal wave patterns. We show that an exponential temporal kernel does not allow static bifurcations such as saddle-node, pitchfork, and in particular, static Turing bifurcations. However, the exponential temporal kernel possesses the important property that it takes into account the finite memory of past activities of neurons, which Green's function does not. Through a dynamic bifurcation analysis, we give explicit bifurcation conditions. Hopf bifurcations lead to temporally non-constant, but spatially constant solutions, but Turing-Hopf bifurcations generate spatially and temporally non-constant solutions, in particular, traveling waves. Bifurcation parameters are the coefficient of the exponential temporal kernel, the transmission speed of neural signals, the time delay rate of synapses, and the ratio of excitatory to inhibitory synaptic weights.

Edge Computing Security of Mobile Communication System Based on Computer Algorithms

With the progress of information technology recently, mobile communication system edge computing (EC) has been widely used in all walks of life, but the traditional mobile communication system EC mode has security problems such as privacy disclosure, malicious tampering, and virus attacks. Computer algorithms has brought new vitality to EC in mobile communication systems. This paper analyzed the application of computer algorithm in EC mode of mobile communication system, and selected 20 users as the research object. This paper adopted traditional computing mode (such as cloud computing) and computer algorithm-based mobile communication system EC security research. This text compared the effects of two modes on security performance, data transmission efficiency, energy consumption, cost savings, and user satisfaction. The experimental results in this paper showed that the average security of EC mode of mobile communication system based on computer algorithm was 84%, and the average data transmission time was 4.8[Formula: see text]s. The energy consumption was 40%, and the cost savings and user satisfaction were 432,000 yuan and 13 points, respectively. Both were superior to the traditional edge counting mode. The EC mode of mobile communication system using computer algorithms can significantly improve the security of mobile communication, data transmission speed, cost savings, user satisfaction, and reduce energy consumption. This model has important significance and value for social development.

Research Progress of High-Speed Data Transmission Technology for Lightweight and Small-Sized Unmanned Aerial Vehicle Platforms

With the continuous development of science and technology, UAV technology has been widely used in various fields. As an essential part, light and small UAV platforms have the advantages of being small, lightweight, and easy to operate and thus have been widely used in aerial photography, monitoring, rescue, and other fields. However, the traditional data transmission method can no longer meet the demand for the data transmission speed and stability of small and light UAV platforms. Wireless optical communication has the advantages of being high-speed and license-free, as well as having a large bandwidth strong anti-interference ability, and good confidentiality. Therefore, this paper aims to study high-speed data transmission technology for light and small UAV platforms to improve their transmission speed and stability. In this paper, the characteristics and advantages of UAV airborne laser communication are first elaborated to illustrate the advancements and importance of data transmission technology based on light and small UAV platforms. Then, the composition of a UAV airborne laser communication system is clarified to illustrate the feasibility of conducting airborne laser communication research. Then, the current domestic and international research status of people on light and small UAV airborne laser communication high-speed data transmission systems is reviewed, and its key technical features are analyzed. Finally, the prospects for its application and development trend are investigated.

High Speed Transmission Characteristics on Glass Based Interposers

Interposers for system in package will became more and more important for advanced electronic systems. As the industry moves toward HPC (High Performance Computing) for huge data transmission with low power consumption. The major engineering requirements for HPC application are highdensity, high speed data transmission, low loss, precision manufacturing and low cost. On the 2.5D heterogenous package structure, key technology is fine wiring connected with CPU chip and HBM chips. The fine wires needed high speed transmission. This paper presents the demonstration of Glass-based twin type interposers, Glass interposer with fine pitch metalized through via and RDL interposer with low loss dielectrics on Glass carrier. We compare twin types of Interposes fabrication process capability with panel size format 300x400mm. Finally, we compare the transmission characteristics using eye diagram for heterogenous integration application. Glass Interposer has low loss glass via, it is effective vertical interconnection. RDL interposer has low loss dielectric layers, excellent transmission characteristics obtained on fine pitch trace area.

Synthesis and Characterization of Hematite Fe2O3 Nanofiller for Enhanced Dielectric and Microwave-Absorbing Properties in PTFE Composites

This paper presents the synthesis of hematite Fe2O3 nanofiller from mill scales and its application in polytetrafluoroethylene (PTFE) composites for enhanced dielectric and microwave-absorbing properties. The nanofiller was obtained through 9 hours of high-energy ball milling, resulting in a particle size reduction 43.6 to 11.05 nm. The PTFE/Fe2O3 composites were fabricated by dispersing different concentration of Fe2O3 nanofillers using the dry powder processing technique. The structural and morphological characterization of the nanofiller and PTFE/Fe2O3 composites was carried out using X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM), respectively. The composites’ microwave absorption properties were analyzed utilizing vector network analyzer (VNA) measurements in the 8–12 GHz frequency range. Based on the findings from the results, as the percentage of filler increased from 5 to 15%wt, the composites' loss tangent and dielectric constant increased from 0.0272 to 0.0478 and 2.12 to 3.25, respectively, while their reduced signal transmission speed was between 2.21 and 2.07 x 108 m/s at 8 GHz and from 2.24 to 2.11 x 108 m/s at 12 GHz. These findings demonstrate that Fe2O3 nanoparticles are a suitable material for developing microwave-absorbing polymer composites within the 8–12 GHz frequency range.

Feature of the forward error correction constructions for optical transport networks

Due to the rapid increase of network traffic in the last few years, many telecommunication operators have started transitions to 100G optical networks and beyond. However, high speed optical networks need more efficient Forward Error Correction (FEC) codes to deal with the optical impairments. Forward error correction is widely used in optical communications to improve error correction and extend optical transmission distance. It is also used to reduce optical transmitter power and system costs. In response to the rapid growth of optical communications, the ITU-T has started researching FEC coding and has recommended ITU-T G.709 and G.975.1. As optical transmission systems evolve towards longer transmission distance, greater capacity, and speeds of 100G and beyond a variety of unwanted effects are seriously affecting smooth evolution. In optical transport network, FEC is getting more and more important as spectral efficiency is increasing. As 100G system is commercialized, there are some trends in the evolution of FEC, for example overhead is increased from 7% to 20% or even more. High-performance FEC codes are therefore being developed so that higher net coding gain (NCG) and better error correction can be achieved. The Optical Internetworking Forum (OIF) suggests that soft-decision forward-error correction (SD-FEC) with a redundancy of 20% and beyond be used in a 100G DWDM coherent system. The use of advanced modulation formats is a promising solution for attaining such high data rates in optical networks. However, as a signal constellation grows in size, so does the optical signal to signal-to-noise ratio it requires to achieve a certain bit error rate (BER). This will degrade the error correction capability. Decoding is moving from hard to soft. Vendors are developing their own advanced codes instead of using codes recommended by ITU-T. Because different application systems have different decoding performance, latency, power and cost requirements, FEC systems with various transmission overhead, implementation complexity, burst-error correction ability and error floor are available in today’s market. Soft-decision FEC often uses turbo product codes and low density parity check (LDPC) codes. In research area, new codes such as LDPC codes and their different varieties are introduced into optical communication. Optimized codeword structure and decoding algorithm that provides low BER. LDPC codes can be very powerful, but their practical implementation for optical communications links at ultra-high data rates remains a challenge since the decoding of the code requires soft-decision bits about the received bits. A family of structured codes known as quasi-cyclic LDPC codes, whose common structural properties can be exploited by unified encoding and decoding architectures to reduce the complexity in implementation.

Use of the 433MHz band for underwater communications in controlled environments

This research aims to design and implement an underwater communication system using radio frequency modules and Arduino. Underwater wireless communication is challenging due to the attenuation of electromagnetic waves in water. However, radio frequency signals in the 433MHz range and the added antenna have shown successful data transfer. For this purpose, measurements are made at different distances, and data is collected in the aquatic environment and free space. A comparative analysis of the values of arrival powers and losses in the studied environment is carried out to verify the efficiency of this study in terms of range, transmission speed, and reliability.

Chinese expert consensus on the process of 5G+ helicopter aviation medical rescue (2024 edition)

To address the lagging status of aviation medical rescue in China compared to developed countries, the focus is on critical weaknesses such as the inadequate aviation rescue communication network and communication technology. The team has established an efficient network among rescue helicopters, emergency centers, and hospitals using 5G technology, achieving millisecond-level speed and real-time data transmission. The Professional Committee of Emergency Resuscitation and Disaster Medicine of Chinese Medical Doctor Association integrated emergency experts, medical institutions, and emergency rescue teams to jointly draft Chinese expert consensus on 5G+ helicopter aviation medical rescue (2024 edition). The consensus recommends the widespread application of 5G technology in aviation medical rescue, utilizing 5G technology for warning and dispatch during the initiation of aviation medical rescue, and using 5G technology for real-time transmission of vital signs and high-definition videos to emergency centers and receiving hospitals during rescue operations and flight. Successful cases fully demonstrate the potential of 5G technology in aviation medical rescue. The consensus aims to standardize and guide 5G+ helicopter medical rescue, ultimately achieving the goal of patients being "admitted upon boarding".

Neural-network-based carrier-less amplitude phase modulated signal generation and end-to-end optimization for fiber-terahertz integrated communication system.

In fiber-terahertz integrated communication systems, nonlinear distortion and inter-symbol interference (ISI) will degrade transmission performance. Pre-compensation is an efficient method to handle the channel distortion as it can avoid noise boosting during channel compensation and reduce receiver side signal processing algorithmic complexity at user-end (UE) considering the asymmetric access scenario. In this paper, we propose and experimentally demonstrate a neural-network (NN)-based carrier-less amplitude phase (CAP) modulated signal generation and end-to-end optimization method for a fiber-terahertz integrated communication system. The CAP signal is generated directly from quadrature amplitude modulation symbols and pre-compensated through a transmitter NN, which allows the receiver to demodulate the signal with simple linear digital signal process (DSP). In generating the CAP signal, the NN based transmitter learns a group of filters, which can generate, up-convert, and pre-compensate the signals. Based on the proposed method, a fiber-terahertz integration access system at 220 GHz is demonstrated and a sensitivity gain of 1.2 dB is achieved at a transmission speed of 50 Gbps and the forward error correction (FEC) bit error rate (BER) threshold of 1 × 10-2 compared with the baseline after 10-km fiber transmission and 1-m wireless delivering.