Long-range Communication Research Articles

Optimizations of Double Titanium Nitride Thermo-Optic Phase-Shifter Heaters Using SOI Technology.

A commercial thermo-optic phase shifter (TOPS) is an efficient solution to the imbalance problem in the fabrication process of Mach-Zehnder modulator (MZM) arms. The TOPS consumes electrical power and transforms it into thermal energy, which changes the real part of the effective refractive index at the waveguide and adjusts the MZM transfer function to work in the linear region. The common model being used today is constructed with only one heater; however, this solution requires more electrical power, which can increase the transmitter system cost. To reduce the system energy cost, we propose a pioneering optimal double titanium nitride heater model under forward biasing at 1550 nm wavelength using the standard silicon-on-insulator technology. Numerical investigations were carried out on the key relative geometrical parameters, heat distribution at the silicon layer, thermal crosstalk, and laser wavelength drift. Results show that the optimal TOPS design can function with a low electrical power of 19.1 mW to achieve a π-phase shift, with a low thermal crosstalk of 0.404 and very low optical losses over 1 mm length. Thus, the proposed device can be used for improving the imbalance problem in MZMs with low electrical power consumption and low losses. This functionality can be utilized to obtain better performances in transmitter systems for data centers and long-range optical communication system applications.

Interpreting phase shifts of basin-scale arrivals observed in the North Pacific

The 75 Hz Kauai Beacon is well situated for observing the North Pacific Ocean acoustically. Somewhat conveniently, three ocean observing networks, with acoustic receivers located within the deep sound channel: two observatories 4 mm to the East (RCO: Regional Cabled Observatory and MARS: Monterey Accelerated Research System), and the International Monitoring Station at Wake Island 3.5mm to the West. During April–June of 2023, the Beacon transmitted a 37.5 Hz bandwidth m-sequence signal several times a day every 4 days. Upon processing, a persistent arrival structure is identified, which for which each arrival exhibits a unique, yet relatively steady phase over the course of a 20-min transmission. Leveraging acoustic propagation models to better understand the effect of the fluctuating ocean environment, we address the stability of the arrivals over the 20-min transmissions, from hour to hour, and over the course of the 3-month study. This includes examination of potential causes for the slow-phase shifts observed at all of the stations, and how it relates to Doppler. This talk concludes with a discussion on the future utility and research topics of interest, including long-range geo-positioning (underwater GPS), communications, thermometry, and tomography.

FEMTOSAT-Based Air Quality Monitoring: Leveraging Satellite Data and LoRa Communication for Improved AQI Predictions

The exponential growth of the global population has given rise to an alarming surge in air pollution levels, casting profound repercussions on economies, ecosystems, and human well-being. The predominant method for assessing air quality involves the deployment of sensors atop buildings at regular intervals. However, this approach faces significant drawbacks, including heightened energy consumption associated with each building's sensor infrastructure and its inapplicability in sparsely populated rural areas. Addressing these limitations, the utilization of FEMTOSAT technology emerges as a solution, capitalizing on satellite data for autonomous air pollution monitoring, analysis, and mitigation. Amidst the evolving scientific landscape, the integration of Low Power Wide Area Network (LoRa) technology assumes a pivotal role within the Internet of Things (IoT), facilitating long-range data communication with minimal power consumption. In this context, LoRa communication serves as the conduit for transmitting and receiving data from satellites via RF signals. The satellite-derived environmental data, thus collected, serves as the foundation for computing the Air Quality Index (AQI) at specific locations, a critical metric that informs us about air quality conditions, whether pristine or contaminated. The AQI computation factors in various pollutants, including NO2, CO, O3, PM2.5, SO2, and PM10, all of which significantly influence air quality. This study employs a range of machine learning (ML) techniques, including time series analysis, linear regression, Support Vector Machines (SVM), and logistic regression, to predict and forecast AQI values. These models amalgamate AQI data from diverse sources, yielding robust and dependable AQI prediction models. Notably, modern sensor technology simplifies and enhances data collection accuracy. In the realm of environmental data analysis, only ML algorithms can grapple with the complexity of processing vast datasets to generate precise and trustworthy predictions. The incorporation of integrated sensors as payload in the Femto Sat mission epitomizes the mission's objectives. This system is characterized by its cost-effectiveness, lightweight design, durability, redundancy, and user-friendly interface, requiring minimal power consumption for operation.

Ebola Virus Uses Tunneling Nanotubes as an Alternate Route of Dissemination.

Ebola virus (EBOV) disease is marked by rapid virus replication and spread. EBOV enters the cell by macropinocytosis and replicates in the cytoplasm, and nascent virions egress from the cell surface to infect neighboring cells. Here, we show that EBOV uses an alternate route to disseminate: tunneling nanotubes (TNTs). TNTs, an actin-based long-range intercellular communication system, allows for direct exchange of cytosolic constituents between cells. Using live, scanning electron, and high-resolution quantitative 3-dimensional microscopy, we show that EBOV infection of primary human cells results in the enhanced formation of TNTs containing viral nucleocapsids. TNTs promote the intercellular transfer of nucleocapsids in the absence of live virus, and virus could replicate in cells devoid of entry factors after initial stall. Our studies suggest an alternate model of EBOV dissemination within the host, laying the groundwork for further investigations into the pathogenesis of filoviruses and, importantly, stimulating new areas of antiviral design.

When the connectivity is lost: infrastructural uncertainty and reaction to it amongst the tundra nomads of the Yamalo-Nenets Autonomous Okrug

The present paper contributes to the study of ‘infrastructural failures’ as one of the rapidly developing in re-cent times areas of the anthropology of infrastructure. In the focus of the research is a ‘failure’ of the satellite tele-phone communications in Russian Arctic, which occurred as a result of the decision of one of the providers, Globalstar inc., to withdraw from the Russian market in March 2022. This provider was particularly popular amongst the groups of the native population of Russian Arctic due to low prices for the service and equipment. In the paper, the ethnographic data collected during a fieldwork amongst reindeer herding nomads of Nadym District of the Yamalo-Nenets Autonomous Okrug, Russia, are used, on the basis of which the study is carried out on how the tundra nomads were adapting to the failure and overcoming its consequences. The paper starts with a short historical review of the development of long-range communications in tundra and the social norms, strategies, and behavioural patterns formed at different times amongst the reindeer herders in respect to these communications. This review, the materials for which comprised published literature and fieldwork records of the author collected in the late 1990s — early 2000s, demonstrates that up until the arrival of mobile and satellite telephones in tundra during the second decade of the 21st century, radiocommunications of the reindeer herders were, firstly, public and, secondly, relied in messaging on the social networks and mutual obligations of the nomadic groups with regard to transferring information. The review is followed by the description and analysis of the field data collected by the author during the fieldwork in August 2022. It is shown that the loss of the satellite connectivity in the spring of that year disturbed the reindeer herders very much and even caused a change in the movement routes of some of their groups. However, the herders soon managed to adapt to the new conditions. For that, the mobile phones, which were working on a part of the migration territory of the herders, were employed, as well as, impor-tantly, there were restored the social networks and obligations with respect to the information transfer that allowed reliable and relatively fast communications with the locations where the mobile connectivity was lacking. As the result, the communications once again became public, but the serious problems, which might have been caused by the interruption of the satellite connectivity, were able to be avoided. Meanwhile, the acute feeling of uncer-tainty that the herders were experiencing after the failure of the satellite connectivity, shows that the role of the long-range radiocommunications in their lives has increased significantly over the last two decades. The results of the study are also discussed in the context of the recent hypothesis on the “societies of the failure normality”.

Modeling and Optimization of LoRa Networks under Multiple Constraints.

With the access of massive terminals of the Internet of Things (IoT), the low-power wide-area networks (LPWAN) applications represented by Long Range Radio (LoRa) will grow extensively in the future. The specific Long Range Wide Area Network (LoRaWAN) protocol within the LoRa network considers both low power consumption and long-range communication. It can optimize data transmission to achieve low communication latency, ensuring a responsive system and a favorable user experience. However, due to the limited resources in LoRa networks, if certain terminals have heavy traffic loads, it may result in unfair impacts on other terminals, leading to increased data transmission latency and disrupted operations for other terminals. Therefore, effectively optimizing resource allocation in LoRa networks has become a key issue in enhancing LoRa transmission performance. In this paper, a Mixed Integer Linear Programming (MILP) model is proposed to minimize network energy consumption under the maximization of user fairness as the optimization goal, which considers the constraints in the system to achieve adaptive resource allocation for spreading factor and transmission power. In addition, an efficient algorithm is proposed to solve this optimization problem by combining the Gurobi mathematical solver and heuristic genetic algorithm. The numerical results show that the proposed algorithm can significantly reduce the number of packet collisions, effectively minimize network energy consumption, as well as offering favorable fairness among terminals.

433Mhz based Robot using PID (Proportional Integral Derivative) for Precise Facing Direction

This research endeavor aims to evaluate the effectiveness of the robot's direction control system by employing PID (Proportional Integral Derivative) output and utilizing wireless communication LoRa E32 433MHz. The experimental robot used in this study was a tank model robot equipped with 4 channels of control. LoRa was implemented in the robot control system, in conjunction with an Android control application, through serial data communication. The LoRa E32 module system was selected based on its established reliability in long-range communication applications. However, encountered challenges included the sluggishness of data transmission when using LoRa for transferring control data and the decreased performance of the robot under Non-Line of Sight conditions. To overcome these challenges, the PID method was employed to generate control data for the robot, thereby minimizing the error associated with controlling its movements. The PID system utilized feedback from a compass sensor (HMC5883L) to evaluate the setpoint data transmitted by the user, employing Kp, Ki, and Kd in calculations to enable smooth movements toward the setpoint. The findings of this study regarding the direct control of the robot using wireless LoRa E32 communication demonstrated an error range of 0.6% to 13.34%. A trial-and-error approach for control variables determined the optimal values for Kp, Ki, and Kd as 10, 0.1, and 1.5, respectively. Future investigations can integrate additional methodologies to precisely and accurately determine the PID constants (Kp, Ki, and Kd) mathematically.

Long-Range Underwater Acoustic Channel Estimation

Long-range underwater acoustic communication (LR-UWAC) is an essential technique for applications such as the control of unmanned underwater vehicles, gliders, or tactical submarines for long-term monitoring tasks. While techniques for estimating the channel impulse response (CIR) of short-range UWAC have been successfully applied, this is not the case for LR-UWAC. Here, the main challenge is to handle the diverse channel structure, which can be of a sparse or a non-sparse structure. In this paper, we propose a robust channel estimator for LR-UWAC. Our solution includes a switching mechanism to classify the channel as either sparse or non-sparse. In its sparse form, the LR-UWAC channel is characterized by a long time delay spread, time-invariant characteristics, and a block structure. Thus, we propose a non-trivial combination of the block subspace pursuit and the distributed subspace pursuit algorithms to exploit the channel’s block structure. For non-sparse LR-UWAC channel structures, we approximate the received signal as Gaussian, and derive a maximum-likelihood (ML) estimator to separate the non-resolvable multipath. Extensive numerical simulation and results from two long-range sea experiments demonstrate the efficiency of our approach in identifying the channel’s structure, and to accurately estimate the channel compared to state-of-the-art benchmarks.

Implementing and developing secure low-cost long-range system using speech signal processing

In the proposed work, we present a secure low-cost speech communication system for long-distance communication. The system utilizes long range (LoRa) technology to transmit speech signals. LoRa technology uses spread-spectrum modulation to enable long-range communication with low power consumption. LoRa modulation allows for data transfer at a slow speed, typically below 22 kbps, which makes it infeasible for transmitting speech. To address this limitation, we suggest a speech coding technique that reduces the overall data rate of speech signals to below 7.5 kbps. This lower rate is more compatible with the LoRa module and ideal for transmitting speech. Moreover, this technique can improve the LoRa transmission range. Additionally, we have developed an encryption-decryption method to ensure the privacy of the messages and prevent unauthorized access by third parties.

Long Range RF- Text based Communication System

Abstract: With the growth of the Internet of Things (IoT) and other wireless applications in recent years the need for long-range and low-power communication systems has increased. This issue can be resolved by application of LoRa (Long Range) technology, which offers a long-range, low-power, and dependable communication system. LoRa is a wireless modulation technique derived from Chirp Spread Spectrum (CSS) technology. It encodes information on radio waves using chirp pulses in a way similar to the communication principles used naturally by dolphins and bats. LoRa modulated transmission is robust against disturbances and can be received across large distances. In this paper a study on long-range RF text-based communication utilizing LoRa module is presented

STAJe−: A Supersonic Flight Program STAJe− 1 Payload Design and System Study

The STAJe− flight program is the latest implementation of a university-based supersonic and hypersonic flight-test program. In the first flight, which is the subject of this study, the focus is on evaluating the suitability of commercial off-the-shelf electronic hardware, additively manufactured internal payload structures, and a long-range communications technique in the challenging environment presented by flight at high supersonic Mach numbers. These items can significantly reduce the cost of a flight experiment, and thus lower the threshold for flight experimentation. The scientific objectives of this flight are to collect pressure and temperature data on the whole trajectory to compare to numerical models, to optically measure the temperature of composite fins mounted on the payload, and to eject the flight module from the rocket assembly and track its location for subsequent recovery. Design calculations for the tracking system are presented alongside experimental results from ground tests demonstrating the suitability of the system. Furthermore, a one-dimensional calculation of the external wall temperatures over the trajectory is presented, which shows that internal systems are sufficiently protected from the harsh environment. Although the materials are shown to be appropriate for the flight, a layer of cork will be added to parts of the payload to further reduce the chance of structural failure. In addition, it is shown that a pneumatic ejection system is suited to overcoming the drag forces on the front of the rocket to initiate separation.

LoRa-Based Low-Cost Nanosatellite for Emerging Communication Networks in Complex Scenarios

Wireless broadband coverage has reached 95% worldwide. However, its trend is expected to stay the same in the following years, presenting challenges for scenarios such as remote villages and their surrounding environments. Inaccessibility to these areas for installing terrestrial base stations is the main challenge to bridge the connectivity gap. In addition, there are emergencies, for instance, earthquakes or war areas, that require a fast communication reaction by developing networks that are less susceptible to disruption. Therefore, we propose a low-cost, green-based nanosatellite system to provide complete coverage in hard-to-reach areas using long-range communication. The system comprises a pilot station, a base station, and a CubeSat with sensor data collector capabilities acting as a repeater. Our system can be built within hours with a 3D printer using common material, providing a flexible environment where components can be replaced freely according to user requirements, such as sensors and communication protocols. The experiments are performed in Spain by two test sets validating the communication among all components, with RSSI values below −148 dBm and the longest distance above 14 km. We highlight the reduction in the environmental impact of this proposal using a balloon-based launch platform that contributes to sustainable development.

Unveiling LoRa's Oceanic Reach: Assessing the Coverage of the Azores LoRaWAN Network from an Island.

In maritime settings, effective communication between vessels and land infrastructure is crucial, but existing technologies often prove impractical for energy-sensitive IoT applications, like deploying sensors at sea. In this study, we explore the viability of a low-power, cost-effective wireless communication solution for maritime sensing data. Specifically, we conduct an experimental assessment of the Azorean Long Range Wide Area Network (LoRaWAN) coverage. Our tests involve positioning the gateway at the island's highest point and installing end nodes on medium-sized fishing vessels. Through measurements of received signal strength indicator (RSSI), signal-to-noise ratio (SNR), and lines of sight (LOS), we showcase the potential of LoRaWAN transmissions to achieve communication distances exceeding 130 km in a LOS-free scenario over the ocean. These findings highlight the promising capabilities of LoRaWAN for reliable and long-range maritime communication of sensing data.

Frequency Shift Keying-Based Long-Range Underwater Communication for Consecutive Channel Estimation and Compensation Using Chirp Waveform Symbol Signals

Currently, the demand for long-range underwater communication (UWC) is increasing. Conventional long-range UWC studies utilize vertical line array (VLA) and equalization techniques such as TRM and DFE to mitigate the long multi-path delay. However, recently developed underwater platforms such as unmanned underwater vehicles (UUVs) utilize a single hydrophone, and it is hard to apply the conventional long-range UWC system to these platforms. This paper proposes frequency shifting-based modulation to overcome the large multi-path delay without any optimization or training symbol. Unlike FSK, the proposed modulation method transmits the data using linear frequency modulation (LFM). The proposed demodulation method estimates the multi-path delay using data-modulated LFM and utilizes the estimated multi-path to compensate for the subsequent data signal. Therefore, the proposed method has better BER performance than FSK, and it is demonstrated through a simulation and ocean experiment with a single hydrophone.

Intercellular crosstalk mediated by tunneling nanotubes between central nervous system cells. What we need to advance.

Long-range intercellular communication between Central Nervous System (CNS) cells is an essential process for preserving CNS homeostasis. Paracrine signaling, extracellular vesicles, neurotransmitters and synapses are well-known mechanisms involved. A new form of intercellular crosstalk mechanism based on Tunneling Nanotubes (TNTs), suggests a new way to understand how neural cells interact with each other in controlling CNS functions. TNTs are long intercellular bridges that allow the intercellular transfer of cargoes and signals from one cell to another contributing to the control of tissue functionality. CNS cells communicate with each other via TNTs, through which ions, organelles and other signals are exchanged. Unfortunately, almost all these results were obtained through 2D in-vitro models, and fundamental mechanisms underlying TNTs-formation still remain elusive. Consequently, many questions remain open, and TNTs role in CNS remains largely unknown. In this review, we briefly discuss the state of the art regarding TNTs identification and function. We highlight the gaps in the knowledge of TNTs and discuss what is needed to accelerate TNTs-research in CNS-physiology. To this end, it is necessary to: 1) Develop an ad-hoc TNTs-imaging and software-assisted processing tool to improve TNTs-identification and quantification, 2) Identify specific molecular pathways involved into TNTs-formation, 3) Use in-vitro 3D-CNS and animal models to investigate TNTs-role in a more physiological context pushing the limit of live-microscopy techniques. Although there are still many steps to be taken, we believe that the study of TNTs is a new and fascinating frontier that could significantly contribute to deciphering CNS physiology.

IoT BASED SMART ENERGY METER USING LoRa TECHNOLOGY

The objective of this paper is to provide a brief overview of how smart energy meters can benefit from incorporating LoRa-WAN and IoT applications. This paper proposes the use of LoRa-WAN and IoT applications in smart energy meters to enable real-time monitoring and calculation of power consumption. In today's technology-driven world, power management is crucial for the efficient operation of digital systems, and excessive power consumption can lead to system failures. By incorporating a LoRa unit into the design, the system's communication range can be extended to multiple locations within the specified range, as LoRa supports the deployment of numerous nodes. Furthermore, LoRa's bi- directional communication capability enhances the system's functionality. Compared to Wi-Fi-based IoT systems, which typically require multiple access points to cover large areas, the proposed LoRa-based solution offers cost advantages. By implementing the suggested software version on the devices, users can monitor their power consumption remotely and take necessary actions to optimize energy usage. Keywords— Smart Energy Meters, LoRa-WAN, IoT applications, Power Consumption, Long-range Communication, Bi-directional Communication, Cost-effective Solution

An Efficient Adaptive Data-Link-Layer Architecture for LoRa Networks

LoRa is one of the most popular low-power wireless network technologies for implementation of the Internet of Things, with the advantage of providing long-range communication, but lower data rates, when compared with technologies such as Zigbee or Bluetooth. LoRa is a single-channel physical layer technology on top of which LoRaWAN implements a more complex multi-channel network with enhanced functionalities, such as adaptive data rate. However, LoRaWAN relies on expensive hardware to support these functionalities. This paper proposes a LoRa data-link-layer architecture based on a multi-layer star network topology that adapts relevant LoRa parameters for each end node dynamically taking into account its link distance and quality in order to balance communication range and energy consumption. The developed solution is comprised of multiple components, including a LoRa parameter calculator to help the user to configure the network parameters, a contention-free MAC protocol to avoid collisions, and an adaptive spreading factor and transmission power mechanism. These components work together to ensure a more efficient use of the chosen ISM band and end node resources, but with low-cost implementation and operation requirements.

Analysis of atmospheric attenuation of a FSO–WDM system for long-range communication

Abstract An FSO system can provide a solution to the problem of last-mile connectivity while also offering a high degree of security and a large capacity for high-speed information transmission, making it a versatile and powerful option for data communication. Despite the above-mentioned advantages, some factors have to be considered when establishing long-range communication, one such factor is atmospheric turbulence (haze, light fog, moderate fog) which degrades the ideal characteristics of the FSO channel and causes a loss in the signal’s power. This loss of power during transmission can be improved by using suitable amplifiers (hybrid optical amplifier, semiconductor optical amplifier) to provide better performance. The next-generation networks must be capable of supporting a significant amount of backhaul data traffic, accommodating a larger number of users, and increasing channel capacity to meet the demands of modern data communication. By implementing wavelength division multiplexing (WDM) and free space optical (FSO) communication techniques, the capacity of the channel can be increased, and more users can be accommodated. The maximum link length offered by the FSO–WDM system has been investigated with hybrid optical amplifier considering the minimum bit error rate, which can provide reliable and long-distance communication.

Abstract P3165: Spectrin-based Regulation Of Exosome Secretion In Cardiac Fibroblasts

Cardiac fibroblasts (CFs) not only modulate the extracellular matrix under physiological conditions, but also have the ability to sense local injury and respond with a phenotypic change and increased paracrine communication to distal cells. While a myriad of studies have focused on identifying the paracrine signals involved in recruitment and activation of CFs, the manner by which CF paracrine communication networks are tuned in response to chronic stress remains unclear. Previously, our lab found that stress-induced loss of the cytoskeletal protein, β IV -spectrin, regulates the CF phenotype and fibrosis. Therefore, we hypothesized that degradation of β IV -spectrin is a critical step in stress-induced communication involved in recruitment of distal CFs. In this study, we first collected conditioned media from WT and β IV -spectrin deficient (qv 4J ) CFs to test the effects on quiescent WT CFs. We found that the CFs treated with qv 4J -conditioned media showed increased proliferation and compaction rates, as well as altered gene expression in the recipient cells compared to those treated with WT-conditioned media. To further explore the role of β IV -spectrin in paracrine signaling, we isolated exosomes from WT- and qv 4J -conditioned media. We found that loss of β IV -spectrin in CFs resulted in an increased concentration of exosomes in conditioned media, that also induced increased proliferation in quiescent CFs. Furthermore, we found that genetic mice expressing degradation-resistant β IV -spectrin ( qv 3J mice) showed impaired CF recruitment and activation following myocardial infarction (MI) together with increased mortality and impaired fibrotic remodeling compared to WT. Finally, we demonstrate that exosomes from a WT-MI heart can improve fibrotic remodeling in qv 3J mice following MI. Our work identifies a novel role of the spectrin-based pathway in facilitating long-range communication in response to chronic stress.

Inference of long-range cell-cell force transmission from ECM remodeling fluctuations

Cells sense, manipulate and respond to their mechanical microenvironment in a plethora of physiological processes, yet the understanding of how cells transmit, receive and interpret environmental cues to communicate with distant cells is severely limited due to lack of tools to quantitatively infer the complex tangle of dynamic cell-cell interactions in complicated environments. We present a computational method to systematically infer and quantify long-range cell-cell force transmission through the extracellular matrix (cell-ECM-cell communication) by correlating ECM remodeling fluctuations in between communicating cells and demonstrating that these fluctuations contain sufficient information to define unique signatures that robustly distinguish between different pairs of communicating cells. We demonstrate our method with finite element simulations and live 3D imaging of fibroblasts and cancer cells embedded in fibrin gels. While previous studies relied on the formation of a visible fibrous ‘band’ extending between cells to inform on mechanical communication, our method detected mechanical propagation even in cases where visible bands never formed. We revealed that while contractility is required, band formation is not necessary, for cell-ECM-cell communication, and that mechanical signals propagate from one cell to another even upon massive reduction in their contractility. Our method sets the stage to measure the fundamental aspects of intercellular long-range mechanical communication in physiological contexts and may provide a new functional readout for high content 3D image-based screening. The ability to infer cell-ECM-cell communication using standard confocal microscopy holds the promise for wide use and democratizing the method.