Long-distance Signal Transmission Research Articles

Photonic architecture for remote multi-parameter measurement and transmission of microwave signals

Photonic architecture for remote multi-parameter measurement and transmission of microwave signals

5G NB-IoT System Integrated with High-Performance Fiber Sensor Inspired by Cirrus and Spider Structures.

Real-time telemedicine detection can solve the problem of the shortage of public medical resources caused by the coming aging society. However, the development of such an integrated monitoring system is hampered by the need for high-performance sensors and the strict-requirement of long-distance signal transmission and reproduction. Here, a bionic crack-spring fiber sensor (CSFS) inspired by spider leg and cirrus whiskers for stretchable and weavable electronics is reported. Trans-scale conductive percolation networks of multilayer graphene around the surface of outer spring-like Polyethylene terephthalate (PET) fibers and printing Ag enable a high sensitivity of 28475.6 and broad sensing range over 250%. The electromechanical changes in different stretching stages are simulated by Comsol to explain the response mechanism. The CSFS is incorporated into the fabric and realized the human-machine interactions (HMIs) for robot control. Furthermore, the 5G Narrowband Internet of Things (NB-IoT) system is developed for human healthcare data collection, transmission, and reproduction together with the integration of the CSFS, illustrating the huge potential of the approach in human-machine communication interfaces and intelligent telemedicine rehabilitation and diagnosis monitoring.

Ca2+/calmodulin-mediated desensitization of glutamate receptors shapes plant systemic wound signalling and anti-herbivore defence.

Plants rely on systemic signalling mechanisms to establish whole-body defence in response to insect and nematode attacks. GLUTAMATE RECEPTOR-LIKE (GLR) genes have been implicated in long-distance transmission of wound signals to initiate the accumulation of the defence hormone jasmonate (JA) at undamaged distal sites. The systemic signalling entails the activation of Ca2+-permeable GLR channels by wound-released glutamate, triggering membrane depolarization and cytosolic Ca2+ influx throughout the whole plant. The systemic electrical and calcium signals rapidly dissipate to restore the resting state, partially due to desensitization of the GLR channels. Here we report the discovery of calmodulin-mediated, Ca2+-dependent desensitization of GLR channels, revealing a negative feedback loop in the orchestration of plant systemic wound responses. A CRISPR-engineered GLR3.3 allele with impaired desensitization showed prolonged systemic electrical signalling and Ca2+ waves, leading to enhanced plant defence against herbivores. Moreover, this Ca2+/calmodulin-mediated desensitization of GLR channels is a highly conserved mechanism in plants, providing a potential target for engineering anti-herbivore defence in crops.

NTIMP1—A Fast Pulse Readout Chip With 1.2 V Power Supply Applied to the Diamond Detector in HIAF

A very fast pulse readout ASIC, NTIMP1, with 1.2 V power supply is presented in this work. It is going to be used as front-end electronics (FEE) for reading out the diamond detector signals in the TOF (Time of Flight) wall of RIBLL2 experiment of the High Intensity Heavy Ion Accelerator Facility (HIAF), China. So that an 8-channel fast front-edge readout chip named as NTIMP1 is proposed in this work. Each channel of NTIMP1 has a high-bandwidth preamplifier (with adjustable thresholds) dealing with differential current input, a fast hysteresis discriminator, and a LVDS (Low-Voltage Differential Signaling) module ensuring long-distance signal transmission. Fabricated with 0.13 μm standard CMOS Technology, NTIMP1 can get an input ranging from 2 fC to 2000 fC and the input impedance of the preamplifier can be adjusted externally with an off-chip resistor, so as to match with the electrode impedance of diamond detector. The bandwidth of the preamplifier is 495.5 MHz, which allows a very short signal peaking time of no more than 1 ns. The jitter of the leading edge is lower than 15 ps with 100 fC input charge suggesting that NTIMP1 is suitable for high-resolution TOF measurement as well as time-slewing correction.

5G Communication: High Gain Array Antenna Operating at 3.5GHz

—5G technology is leverages advanced antenna technology and wider bandwidth to improve the potential of wireless communication that enables a significant increase in the amount of information that can be transmitted through the wireless system. With its ability to deliver higher data rates and lower latency, 5G promises to support a wide range of applications, from immersive virtual reality to autonomous vehicles.However, 5G communication systems are characterized by poor radiation features, which limit their usefulness in wider operational ranges. To overcome these issues, this project will focus on designing a high-gain array antenna operating at 3.5GHz specifically for 5G communication. A directional patch antenna will be designed for a specific base station to provide high radiation network connectivity and superior communication quality. Moreover, the high-gain array antenna at 3.5GHz will be optimized for long-distance point-to-point connections. In this project, a 4x4 patch antenna will be designed and fabricated using FR4 epoxy material to achieve high gain for long-distance signal transmission.

Construction and Application of On-Line Roof Separation Monitoring System Based on High-Precision FBG Indicator

Aiming at the existing problems of low efficiency, lagging monitoring results, and poor reliability and accuracy in the present roadway roof separation monitoring system, a high-precision Fiber Bragg Grating (FBG) separation indicator is designed through theoretical analysis, numerical simulation, and laboratory tests—according to the fiber grating sensing principle. Based on the Microsoft. Net platform, C# programming language, and VS2010 integrated development tools, the corresponding on-line monitoring software is developed. On this basis, a real-time on-line roof separation monitoring system is proposed. The high-precision FBG separator was calibrated and tested in the laboratory and results suggested that both the left and right arm demonstrate good sensitivity and linearity with linear fitting coefficient values of 0.9981 and 0.9979, respectively. The monitoring system was successfully applied to roof separation monitoring of the #14301 rail roadway in the Shaqu coal mine. The monitoring results showed that the on-line roof separation monitoring system based on the high-precision FBG separation indicator has the advantages of high precision, good stability, and long-distance signal transmission, which can achieve real-time dynamic monitoring and provides an effective method for long-term on-line monitoring of roadway roof separation.

Full-Distance A-RoF Transmission Experiment Utilizing Frequency-Optimized FM Conversion

Advances in the long-distance transmission of wideband A-RoF signals are critical. The world’s longest-class transmission using a practical A-RoF system is currently just over 300 km. In this system, CATV/BS/CS video signals are frequency-multiplexed with a bandwidth of 2.1 GHz and transmitted from broadcaster buildings to houses scattered throughout the country. In recent years, there is a demand to extend this bandwidth to 3.2 GHz in order to multiplex 8K/4K ultra-high-definition video. However, A-RoF transmission over 300 km in the 3.2-GHz bandwidth is difficult and no one has been achieved. Our solution is a new transmitter that improves transmission characteristics by changing the FM center frequency and suppressing harmonics. Our experiments clarified the existence of an optimum FM center frequency that is less affected by self-phase modulation, chromatic dispersion, and residual FM signal degradation. The proposed transmitter achieved the target distance and bandwidth for the first time in the world.

Precision Design and Fabrication of Noise-free High-Frequency Amplifier Board for Enhanced Signal Processing

An optical signal processing system is widely used for long-distance signal transmission with high speed and low attenuation. It plays a fundamental role in optical communication systems that involves transmitting, receiving, amplifying, and manipulating optical signals which are high-frequency signals. This paper portrays the design of a high-frequency amplifier to amplify the low-amplitude high-frequency, electrical signal procured from the optical signal. A four-stage high frequency amplifier has been designed using an AD8009 high-frequency Op-amp for the highest frequency of 1GHz, and for the fastest rise time of 0.35 nanoseconds. This amplifier board incorporates the high-frequency PCB design rules related to the characteristic impedance, impedance matching, signal crosstalk, the propagation delay of the transmission lines, transmission techniques for the ground plane, and termination of transmission lines for the effective use of high-frequency signals. It has also counted on the issues of electromagnetic interference, power supply decoupling, noise, and high-speed operational amplifier. The proposed system resulted in suitable amplification of low amplitude high-frequency electrical signal, having no signal cross-talks, electromagnetic interference, signal ringing, signal reflections, and posed larger bandwidth. The improved quality of high frequency processed signals with good signal integrity and moderate circuit oscillations achieved by this system will benefit the optical communication system.

Elements of a Fiber Optic Communication System

Fiber optic connection is the best option for data transmission at gigabit and above rates. Voice, video, telemetry, and data are all transmitted using this method of communication over great distances and over computer networks or local area networks. By converting electronic signals into light, a fibre optic communication system uses light-wave technology to transfer data via fiber. Large bandwidth, smaller diameter, lightweight, long-distance signal transmission, low attenuation, transmission security, and other outstanding characteristics of this type of communication system make it a key component of any telecommunications infrastructure. The characteristic traits, fundamental components, and other aspects of fibre optic communication systems are highlighted in the information that follows.

Male gopher tortoise (Gopherus polyphemus) concentration-dependent social responses to diluted mental gland pheromones

In complex terrestrial environments, chemical signals can be the most important sensory modality for locating conspecifics for potential mating opportunities, especially in spatially segregated populations or habitats. Organisms must evolve chemical signals to maximize the efficacy of conveying information, particularly in creating trails or mate-choice cues. Long-distance transmission of chemical signals may be an increasingly important management concern for small and fractured populations or potentially threatened species, such as gopher tortoises in the southeastern U.S. Mental gland secretions have been shown to have pheromonal function in gopher tortoises, suggesting a potential role as trail or marking pheromones, allowing males to track females or other males to find females. In this study, male gopher tortoises were given paired presentations of a negative control (distilled water) with serial dilutions (1:4, 1:20, 1:100, and 1:500) of male mental gland secretions. Male tortoises were able to discern treatment differences up to 1:20 diluted secretions, responding with an array of social behaviors (e.g. for the 1:20 dilution trial, carapace alignment and head bobbing occurred more frequently for the mental gland secretion relative to the control; p < 0.01). Multivariate principal components analysis yielded PC1 (including, approach, carapace alignment, head bobbing, tasting air, sniffing, and doubleback) that differed by treatment (p = 0.0007) and also was higher for the 1:20 diluted presentation relative to the 1:500 diluted presentation (p = 0.04). This study provides insight into gopher tortoise ecology, mate-choice, and the utility of environmentally diluted mental gland secretions in the external environment when seeking mating opportunities.

Photonics-Aided Terahertz-Wave Wireless Communication

To meet the upcoming 6G communications challenges, terahertz-wave (THz-wave) wireless data transmission over 100 Gb/s is urgently needed in the short term. However, advanced digital signal processing (DSP) technologies suitable for millimeter-wave (mm-wave) bands cannot satisfy the requirements; increasing the carrier frequencies for more spectra is essential. Photonics-aided THz-wave generation (PTG) technology has become a valid way to solve the bandwidth bottleneck. New progress has been made in PTG by using optical frequency combs and optical modulators. The application of DSP technology for heterodyne detection can not only overcome the nonlinear effect in photoelectric devices but also enhance the receiver sensitivity and spectral efficiency. Multidimensional multiplexing technology can reduce the baud rate of each subchannel to realize the long-distance transmission of THz-wave signals. In this tutorial, we introduce the key technologies and principles of ultrahigh speed and large capacity THz-wave signal transmission. These technologies can effectively improve the transmission capacity and distance and reduce the bandwidth required by optical and electronic equipment.

A Split-Type FMICW-Based Guided Wave Radar With Multisegmental Probe for Liquid Level Measurement

In this paper, a specially designed guided wave radar device for measuring the liquid level in the nuclear industry is proposed. A split-type design is introduced to adapt to a strong radiation environment. An L-band frequency modulated interrupted continuous wave (FMICW) radar is designed to ensure the signal-to-noise ratio of echo signal after long-distance signal transmission, which provides the isolation between transmitter and receiver of more than 60 dB using the gating technology. To overcome the shortcomings of limited installation and maintenance space, a novel coaxial waveguide probe with a multi-segmental structure is proposed and simulated. An adaptive signal processing algorithm is developed to remove false echoes and eliminate measurement fluctuations. A prototype of the proposed measurement system is fabricated and evaluated. Static and dynamic liquid level experiments are performed in an outdoor environment to assess performance and verify the effectiveness of the proposed radar. The results show that the standard deviation measurement error of the proposed radar is within 0.4 cm. The proposed system is expected to have a high potential for applications in liquid level measurement under complex conditions.

Low-cross-talk and multi-channel heterogeneous 13-core four-LP mode fiber with a high refractive index ring and a trench

We propose a heterogeneous 13-core few-mode fiber, which is characterized by the combination of a high refractive index ring and a trench. All cores of the optical fiber can stably transmit L P 01 , L P 11 , L P 21 , and L P 02 modes in the C + L band through structural optimization and numerical analysis. The effective refractive index difference of the L P 21 and L P 02 modes reaches 2 × 10 − 3 , which is conducive to the independent transmission of modes. The trench can effectively suppress the inter-core cross talk below − 50 d B / k m at 1550 nm. The proposed few-mode multi-core fiber is conducive to solving the long-distance signal transmission problem of large capacity and low cross talk in future optical communication systems.

An Innovative Infrastructure Based on Shape-Adaptive RIS for Smart Industrial IoTs

Industrial Internet of Things (IoTs) applications will have higher demands in terms of system capacity and wireless transmission performance in the future. Reconfigurable intelligent surfaces (RIS) for the wireless transmission environment reconstruction is currently a research hotspot in the field of wireless communication. In this paper, RIS is applied to industrial IoTs scenarios, and an innovative infrastructure based on shape-adaptive RIS suitable for smart industrial IoTs is proposed. Based on the many advantages of RIS, the proposed infrastructure can meet the significant demands of industrial IoTs in terms of network coverage, system capacity, transmission rate, and communication security. Further, in order to achieve flexible RIS phase adjustment in wider ranges, in this paper, a shape-adaptive RIS mechanism is proposed to regulate RIS-reflected waves in the shape domain, which can be achieved by scalable RIS unit sizes and macroscopically changeable physical shapes. This mechanism can reduce the requirements for RIS-controller and artificial-unit design and expand the spatial distribution of reflected beams, whereas this is difficult to achieve by conventional regulations in the spatial, time, and frequency domains. The simulation results show that, in terms of system-coverage probability, the system performance of RIS is better than that of general communication systems, and the performance of the deformable RIS-based system is the best. In terms of channel gain, the performance of the deformable RIS is related to its surface size. Moreover, the path loss caused by the long-distance transmission of wireless signals can be compensated for by increasing the RIS surface area.

Ultra-low-latency 8K-video-transmission System Utilizing Whitebox Transponder with Disaggregation Configuration

The demand for low-latency transmission of large-capacity video, such as 4K and 8K, is increasing for various applications such as live-broadcast program production, sports viewing, and medical care. In the broadcast industry, low-latency video transmission is required in remote production, an emerging workflow for outside broadcasting. For ideal remote production, long-distance transmission of uncompressed 8K60p video signals, ultra-low latency less than 16.7 ms, and PTP synchronization through network are required; however, no existing video-transmission system fully satisfy these requirements. We focused on optical transport technologies capable of long-distance and large-capacity communication, which were previously used only in telecommunication-carrier networks. To fully utilize optical transport technologies, we propose the first-ever video-transmission system architecture capable of sending and receiving uncompressed 8K video directly through large-capacity optical paths. A transmission timing control in seamless protection switching is also proposed to improve the tolerance to network impairment. As a means of implementation, we focused on whitebox transponder, an emerging type of optical transponder with a disaggregation configuration. The disaggregation configuration enables flexible configuration changes, additional implementations, and cost reduction by separating various functions of optical transponders and controlling them with a standardized interface. We implemented the ultra-low-latency video-transmission system utilizing whitebox transponder Galileo. We developed a hardware plug-in unit for video transmission (VideoPIU), and software to control the VideoPIU. In the video-transmission experiments with 120-km optical fiber, we confirmed that it was capable of transmitting uncompressed 8K60p video stably in 1.3 ms latency and highly accurate PTP synchronization through the optical network, which was required in the ideal remote production. In addition, the application to immersive sports viewing is also presented. Consequently, excellent potential to support the unprecedented applications is demonstrated.

Signaling and transport processes related to the carnivorous lifestyle of plants living on nutrient-poor soil.

In Eukaryotes, long-distance and rapid signal transmission is required in order to be able to react fast and flexibly to external stimuli. This long-distance signal transmission cannot take place by diffusion of signal molecules from the site of perception to the target tissue, as their speed is insufficient. Therefore, for adequate stimulus transmission, plants as well as animals make use of electrical signal transmission, as this can quickly cover long distances. This update summarises the most important advances in plant electrical signal transduction with a focus on the carnivorous Venus flytrap. It highlights the different types of electrical signals, examines their underlying ion fluxes and summarises the carnivorous processes downstream of the electrical signals.

Hybrid Sapphire Dual-Fabry—Perot-Cavities Sensor for High Temperature and Refractive Index Measurement

We presented a hybrid sapphire dual-Fabry—Perot- cavities sensor for high temperature and refractive index measurement. A double-sided polished sapphire solid wafer is connected in series with a double-sided parallel sapphire C-ring and a single-sided polished sapphire mirror to form the hybrid Fabry—Perot interferometer. The double-sided polished sapphire solid wafer acts as the first Fabry—Perot cavity for temperature sensing, and the sapphire hollow C-ring cavity constitutes the second Fabry—Perot cavity for measuring the refractive index of external environment medium. The single-sided polished sapphire mirror serves as the most distal reflector. Heterogeneous fiber splicing between sapphire fiber and multimode silica fiber is realized to achieve long-distance transmission of interference signals. A series of high temperature measurement experiments range of room temperature to 1080 °C in an air environment and refractive index measurement experiments in a liquid environment were carried out. Based on the changing rates of corresponding Fabry—Perot cavity optical path difference against refractive index and temperature, we calculated the sensitivities of the sensor. The refractive index and temperature sensitivities were 2.0659 × 105 nm/RIU in the RI range of 1.3330∼1.3741 and 7.837 nm/ °C at 1080 °C.

Tubuloglomerular Feedback Synchronization in Nephrovascular Networks.

To perform their functions, the kidneys maintain stable blood perfusion in the face of fluctuations in systemic BP. This is done through autoregulation of blood flow by the generic myogenic response and the kidney-specific tubuloglomerular feedback (TGF) mechanism. The central theme of this paper is that, to achieve autoregulation, nephrons do not work as single units to manage their individual blood flows, but rather communicate electrically over long distances to other nephrons via the vascular tree. Accordingly, we define the nephrovascular unit (NVU) to be a structure consisting of the nephron, glomerulus, afferent arteriole, and efferent arteriole. We discuss features that require and enable distributed autoregulation mediated by TGF across the kidney. These features include the highly variable topology of the renal vasculature which creates variability in circulation and the potential for mismatch between tubular oxygen demand and delivery; the self-sustained oscillations in each NVU arising from the autoregulatory mechanisms; and the presence of extensive gap junctions formed by connexins and their properties that enable long-distance transmission of TGF signals. The existence of TGF synchronization across the renal microvascular network enables an understanding of how NVUs optimize oxygenation-perfusion matching while preventing transmission of high systemic pressure to the glomeruli, which could lead to progressive glomerular and vascular injury.

Hi-speed USB signal long-distance communication and test scheme design based on Ethernet communication

The USB universal serial bus is widely used in host computer control and data information transmission due to its plug-and-play, hot-swap support, and flexible use. However, due to cable loss and USB protocol restrictions, high-speed USB signals can only support a transmission distance of 5 meters. In this paper, there shows an engineering application design of the signal transmission scheme based on the USB signal processing chip CH317. Convert hi-speed USB signal into optical Ethernet signal to achieve long-distance transmission of high-speed USB signals. Since there is no test standard at the application layer for hi-speed USB signal, in this paper design a complete test scheme for this transmission method at the hardware layer and application layer according to the existing test standards of hi-speed USB signal and Ethernet. It has certain reference significance for the application of hi-speed USB signal long-distance transmission in engineering.

Signal Transmission Capability Improvement of a Telemetry Drill String Using the Reflected Signal at the Transmission Line Termination

A telemetry drill string system consists of a string of wired drill pipes, and high-frequency signals pass the adjacent drill pipes through inductive couplers. Such a system is used to upload downhole information at high data transmission rates for measurements while drilling (MWD). Since the signal energy attenuates greatly in the system, many repeaters must be provided to ensure signal transmission. A reduction in the signal transmission in a telemetry drill string can extend the relay distance and improve the reliability of the transmission system. In this study, the transmission characteristic of the rod of the wired drill pipe is studied using transmission line theory, and the transmission characteristic of the inductive coupler is studied using high-frequency circuit theory. Using impedance matching between the transmission line of the rod and the inductive coupler, external impedance compensation elements, including a capacitor and a resistor, are recommended, and the electromagnetic parameters of the wired drill pipe are determined. Based on the determined electromagnetic parameters, certain changes in the external impedance compensation capacitance and resistance can lead to impedance mismatch between the transmission line and the inductive coupler. This will generate a reflected signal at the transmission line, and the vector superposes with the transmitted signal. The terminal reflection coefficient of the transmission line is controlled by increasing the compensation resistance value to enhance the signal amplitude, which can compensate the transmission loss when passing through the inductive coupler to a certain extent. Thus, the signal transmission capability of the telemetry drill string can be improved, allowing for long-distance signal transmission or drastically extending the relay distance, while maintaining a certain channel bandwidth.