PASSWORD-LESS TRUST BASED ACCESS AUTHORIZATION FOR REMOTE INTERNET-OF-THINGS (IOT) DEVICES

The industry is moving away from password-based authorizations as they are often difficult to manage and are associated with various risks. Techniques herein solve an important issue with regard to remote Internet of Things (IoT) gateway access by utilizing a password-less trust-based authentication mechanism through which dynamic trust-based authorizations can be provided for devices utilizing a combination of a user trust score and a device risk profile in a unique manner. Such an approach will improve IoT security and will also help to solve an important security issue within the IoT/industrial world

Development of a remote IoT laboratory for cyber physical systems

A remote Internet of Things (IoT) laboratory has been developed for use in teaching and research of cyber physical systems. The laboratory is configured such that users interact via the web to control and collect data from connected devices. The concept and technology of the remote IoT lab is successfully demonstrated in two applications. First the laboratory is configured for UTChattSat, a ground model small-satellite system (CubeSat) designed to enhance K-12 learning in the space sciences. The system utilizes real-time communication and web-based user control to create a distributed multi-user interface. Second, the laboratory is configured for a distributed sensor network with a single-user interface. The interconnected, real time, and smart system with embedded sensors and processors is used to provide data for assessment of current building energy models. Finally, challenges posed by interconnected and reconfigurable systems and the implementable future works are discussed

Onion growth monitoring system using internet of things and cloud

Many real-time apps acknowledge the different advancements made in many sectors through the usage of new technologies. Using Wireless Sensor Networks and Think speak Cloud; this research paper proposes a remote internet of things (IoT) based onion growth monitoring approach. With the use of the internet of things and wireless sensor networks, the suggested study work improves the traditional approach to onion growing in rural areas. This study proposes the creation and deployment of a thermal-based Internet of Things system within onion farms, with the goal of managing devices such as fans and heaters according to the ideal range of onion production and good onion growth

Energy-Efficient Random Access for LEO Satellite-Assisted 6G Internet of Remote Things

Satellite communication system is expected to play a vital role for realizing various remote internet of things (IoT) applications in 6G vision. Due to unique characteristics of satellite environment, one of the main challenges in this system is to accommodate massive random access (RA) requests of IoT devices while minimizing their energy consumptions. In this paper, we focus on the reliable design and detection of RA preamble to effectively enhance the access efficiency in high-dynamic low-earth-orbit (LEO) scenarios. To avoid additional signaling overhead and detection process, a long preamble sequence is constructed by concatenating the conjugated and circularly shifted replicas of a single root Zadoff-Chu (ZC) sequence in RA procedure. Moreover, we propose a novel impulse-like timing metric based on length-alterable differential cross-correlation (LDCC), that is immune to carrier frequency offset (CFO) and capable of mitigating the impact of noise on timing estimation. Statistical analysis of the proposed metric reveals that increasing correlation length can obviously promote the output signal-to-noise power ratio, and the first-path detection threshold is independent of noise statistics. Simulation results in different LEO scenarios validate the robustness of the proposed method to severe channel distortion, and show that our method can achieve significant performance enhancement in terms of timing estimation accuracy, success probability of first access, and mean normalized access energy, compared with the existing RA methods

On the Influence of Charging Stations Spatial Distribution on Aerial Wireless Networks

Using drones for cellular coverage enhancement is a recent technology that has shown a great potential in various practical scenarios. However, one of the main challenges that limits the performance of drone-enabled wireless networks is the limited flight time. In particular, due to the limited on-board battery size, the drone needs to frequently interrupt its operation and fly back to a charging station to recharge/replace its battery. In addition, the charging station might be responsible to recharge multiple drones. Given that the charging station has limited capacity, it can only serve a finite number of drones simultaneously. Hence, in order to accurately capture the influence of the battery limitation on the performance, it is required to analyze the dynamics of the time spent by the drones at the charging stations. In this paper, we use tools from queuing theory and stochastic geometry to study the influence of each of the charging stations limited capacity and spatial density on the performance of a drone-enabled wireless network

Estudio, diseño e implementación del enlace ascendente de comunicaciones NVIS multiportadora de baja potencia y diversidad de polarización

Cada dia el nombre de dispositius IoT (Internet of Things) és major, apareixent conseqüentment nous protocols i tecnologies radio enfocades a la comunicació d'aquesta mena de dispositius segons les seves necessitats. En el cas de dispositius RIoT (Remote Internet of Things) que es troben en zones molt allunyades d'infraestructures de telecomunicacions o que l'orografia no permet la visió directa entre transmissor i receptor, les comunicacions per satèl·lit i HF (High Frequency) són opcions que poden garantir l'enllaç. En el cas de les comunicacions HF, són una alternativa de baix cost degut a les característiques de propagació de les seves ones capaces de ser reflectides per la ionosfera abastant milers de quilòmetres. A pesar que la banda d'ús (3-30 MHz) es troba molt per sota de la satel·litària, són una opció vàlida per a l'amplada de banda requerida en dispositius RIoT. Respecte als estàndards de les comunicacions HF podem destacar el MIL-STD-188-110D i el STANAG 4539, els quals varien la modulació i l'amplada de banda segons la velocitat de bits requerida. Aquest tipus d'estàndards són genèrics per als subtipus d'enllaços HF: DX (Distance X) per a enllaços superiors a 250 km i NVIS (Near Vertical Incidence Skywave) per a enllaços menors a 250 km. A causa de les diferències en els paràmetres del canal entre tots dos subtipus d'enllaços, els estàndards actuals poden ser més robustos si es basen en un únic subtipus d'enllaç. Per això, a través d'aquesta tesi doctoral, s'ha caracteritzat el canal ionosfèric NVIS a la regió polar antàrtica amb la finalitat de definir un protocol de transmissió de la capa física el més delimitat a les característiques del canal. Amb tal propòsit, pel fet que les modulacions de banda estreta són susceptibles principalment al delay spread del canal es proposa l'ús de la modulació multiportadora OFDM (Orthogonal Frequency Division Multiplexing) a causa del seu disseny capaç d’evitar el delay spread. Amb el propòsit de verificar els resultats, s'ha provat la OFDM dissenyada en un escenari real, mantenint la velocitat de bit i amplada de banda dels estàndards per a poder comparar la robustesa de la comunicació. A més, pel fet que els estàndards no estan enfocats a transmissions de potències molt baixes, en dispositius RIoT la gestió energètica és de gran importància pel fet que es troben fora de la xarxa elèctrica i requereixen altes autonomies energètiques. Per això la recerca s'ha centrat també en l'anàlisi de les modulacions de banda estreta i de la modulació OFDM a molt baixes potències (menors de 6 W). Finalment, per a augmentar més la robustesa de la modulació, s'ha analitzat el comportament de les modulacions de banda estreta i la modulació OFDM fent ús de tècniques de diversitat de polarització com SC (Selection Combining) i EGC (Equal-Gain Combining) en un enllaç SIMO (Single Input Multiple Output) per a rebre les ones ordinària i extraordinària.Cada día el número de dispositivos IoT (Internet of Things) es mayor, apareciendo consecuentemente nuevos protocolos y tecnologías radio enfocadas a la comunicación de este tipo de dispositivos según sus necesidades. En el caso de dispositivos RIoT (Remote Internet of Things) que se encuentran en zonas muy alejadas de infraestructuras de telecomunicaciones o que la orografía no permite la visión directa entre transmisor y receptor, las comunicaciones por satélite y HF (High Frequency) son opciones que pueden garantizar el enlace. En el caso de las comunicaciones HF, son una alternativa de bajo coste debido a las características de propagación de sus ondas capaces de ser reflejadas por la ionosfera abarcando miles de kilómetros. A pesar de que la banda de uso (3-30 MHz) se encuentra muy por debajo de la satelital, son una opción válida para el ancho de banda requerido en dispositivos RIoT. Respecto a los estándares de las comunicaciones HF podemos destacar el MIL-STD-188-110D y el STANAG 4539, los cuales varían la modulación y el ancho de banda según la velocidad de bits requerida. Este tipo de estándares son genéricos para los subtipos de enlaces HF: DX (Distance X) para enlaces superiores a 250 km y NVIS (Near Vertical Incidence Skywave) para enlaces menores a 250 km. Debido a las diferencias en los parámetros del canal entre ambos subtipos de enlaces, los estándares actuales pueden ser más robustos si se basan en un único subtipo de enlace. Por ello, a través de esta tesis doctoral, se ha caracterizado el canal ionosférico NVIS en la región polar antártica con el fin de definir un protocolo de transmisión de la capa física lo más acotado a las características del canal. Con tal propósito, debido a que las modulaciones de banda estrecha son susceptibles principalmente al delay spread del canal se propone el uso de la modulación multiportadora OFDM (Orthogonal Frequency Division Multiplexing) debido a su diseño capaz de evitar el delay spread. Con el propósito de verificar los resultados, se ha probado la OFDM diseñada en un escenario real, manteniendo la velocidad de bit y ancho de banda de los estándares para poder comparar la robustez de la comunicación. Además, debido a que los estándares no están enfocados a transmisiones de potencias muy bajas, en dispositivos RIoT la gestión energética es de gran importancia debido a que se encuentran fuera de la red eléctrica y requieren altas autonomías energéticas. Por ello la investigación se ha centrado también en el análisis de las modulaciones de banda estrecha y de la modulación OFDM a muy bajas potencias (menores de 6 W). Por último, para aumentar más la robustez de la modulación, se ha analizado el comportamiento de las modulaciones de banda estrecha y la modulación OFDM haciendo uso de técnicas de diversidad de polarización como SC (Selection Combining) y EGC (Equal-Gain Combining) en un enlace SIMO (Single Input Multiple Output) para recibir las ondas ordinaria y extraordinaria.The number of IoT (Internet of Things) devices is increasing every day, and consequently new protocols and radio technologies are appearing focused on the communication of these types of devices according to their needs. In the case of RIoT (Remote Internet of Things) devices that are located in areas far away from telecommunications infrastructures or where the orography does not allow direct vision between transmitter and receiver, satellite and HF (High Frequency) communications are options that can guarantee the link. In the case of HF communications, they are a low-cost alternative due to the propagation characteristics of their waves, which are capable of being reflected by the ionosphere, covering thousands of kilometres. Although the band of use (3-30 MHz) is well below than the satellite, they are a valid option for the bandwidth required in RIoT devices. Regarding HF communications standards, we can highlight MIL-STD-188-110D and STANAG 4539, which vary the modulation and bandwidth according to the required bitrate. These standards are generic for HF link subtypes: DX (Distance X) for links above 250 km and NVIS (Near Vertical Incidence Skywave) for links below 250 km. Due to the differences in channel parameters between the two link subtypes, current standards can be more robust if they are based on a single link subtype. Therefore, through this PhD thesis, the NVIS ionospheric channel in the antarctic polar region has been characterised in order to define a physical layer transmission protocol as close as possible to the channel characteristics. For this purpose, due to the fact that narrowband modulations are mainly susceptible to the channel delay spread, the use of OFDM (Orthogonal Frequency Division Multiplexing) multicarrier modulation is proposed due to its design to avoid the delay spread. In order to verify the results, the designed OFDM has been tested in a real scenario, maintaining the bitrate and bandwidth of the standards in order to compare the robustness of the communication. Furthermore, since the standards are not focused on very low power transmissions, in RIoT devices energy management is of great importance because they are off-grid and require high energy autonomy. Therefore, the research has also focused on the analysis of narrowband modulations and OFDM modulation at very low powers (less than 6 W). Finally, to further increase the robustness of the modulation, the behaviour of narrowband modulations and OFDM modulation has been analysed using polarisation diversity techniques such as SC (Selection Combining) and EGC (Equal-Gain Combining) in a SIMO (Single Input Multiple Output) link to receive ordinary and extraordinary waves