Participatory sensing as an enabler for self-organisation in future cellular networks

In this short review paper we summarise the emerging challenges in the field of participatory sensing for the self-organisation of the next generation of wireless cellular networks. We identify the potential of participatory sensing in enabling the self-organisation, deployment optimisation and radio resource management of wireless cellular networks. We also highlight how this approach can meet the future goals for the next generation of cellular system in terms of infrastructure sharing, management of multiple radio access techniques, flexible usage of spectrum and efficient management of very small data cells

Sistema de sensorização móvel e controlo baseado em ZigBee para bicicletas elétricas

Este artigo apresenta um sistema de monitorização e controlo centrado em dispositivos móveis concebido para aplicação em cenários que permitem tirar partido de uma bicicleta eléctrica. A bicicleta, para além de um meio de transporte, é uma excelente ferramenta para a promoção do exercício físico, podendo contribuir para melhorar a aptidão física de utilizadores de diversas faixas etárias. O sistema proposto, baseado numa rede ZigBee, permite recolher sinais fisiológicos dos utilizadores e controlar o motor elétrico da bicicleta de modo a possibilitar a implementação de diversos modos de utilização. Este trabalho descreve a solução utilizada para implementar a comunicação sem fios entre os sensores ZigBee e um smartphone Android, bem como os sensores para monitorização de sinais fisiológicos que foram desenvolvidos. De modo a ajudar a perceber onde este trabalho pode ser aplicado, são explicados alguns modos de utilização baseados no controlo do esforço físico, bem como as vantagens do sistema em relação às bicicletas convencionais e bicicletas estáticas.Fundação para a Ciência e a Tecnologia (FCT

Automatic Energy Saving (AES) Model to Boost Ubiquitous Wireless Sensor Networks (WSNs)

We deploy BT node (sensor) that offers passive and active sensing capability to save energy. BT node works in passive mode for outdoor communication and active for indoor communication. The BT node is supported with novel automatic energy saving (AES) mathematical model to decide either modes. It provides robust and faster communication with less energy consumption. To validate this approach, network simulator-2 (ns2) simulation is used to simulate the behavior of network with the supporting mathematical model. The main objective of this research is to remotely access different types of servers, laptops, desktops and other static and moving objects. This prototype is initially deployed to control MSCS [13] & [14] from remote place through mobile devices. The prototype can further be enhanced to handle several objects simultaneously consuming less energy and resources.http://arxiv.org/abs/1309.450

Energy-Efficient Boarder Node Medium Access Control Protocol for Wireless Sensor Networks

This paper introduces the design, implementation, and performance analysis of the scalable and mobility-aware hybrid protocol named boarder node medium access control (BN-MAC) for wireless sensor networks (WSNs), which leverages the characteristics of scheduled and contention-based MAC protocols. Like contention-based MAC protocols, BN-MAC achieves high channel utilization, network adaptability under heavy traffic and mobility, and low latency and overhead. Like schedule-based MAC protocols, BN-MAC reduces idle listening time, emissions, and collision handling at low cost at one-hop neighbor nodes and achieves high channel utilization under heavy network loads. BN-MAC is particularly designed for region-wise WSNs. Each region is controlled by a boarder node (BN), which is of paramount importance. The BN coordinates with the remaining nodes within and beyond the region. Unlike other hybrid MAC protocols, BN-MAC incorporates three promising models that further reduce the energy consumption, idle listening time, overhearing, and congestion to improve the throughput and reduce the latency. One of the models used with BN-MAC is automatic active and sleep (AAS), which reduces the ideal listening time. When nodes finish their monitoring process, AAS lets them automatically go into the sleep state to avoid the idle listening state. Another model used in BN-MAC is the intelligent decision-making (IDM) model, which helps the nodes sense the nature of the environment. Based on the nature of the environment, the nodes decide whether to use the active or passive mode. This decision power of the nodes further reduces energy consumption because the nodes turn off the radio of the transceiver in the passive mode. The third model is the least-distance smart neighboring search (LDSNS), which determines the shortest efficient path to the one-hop neighbor and also provides cross-layering support to handle the mobility of the nodes. The BN-MAC also incorporates a semi-synchronous feature with a low duty cycle, which is advantageous for reducing the latency and energy consumption for several WSN application areas to improve the throughput. BN-MAC uses a unique window slot size to enhance the contention resolution issue for improved throughput. BN-MAC also prefers to communicate within a one-hop destination using Anycast, which maintains load balancing to maintain network reliability. BN-MAC is introduced with the goal of supporting four major application areas: monitoring and behavioral areas, controlling natural disasters, human-centric applications, and tracking mobility and static home automation devices from remote places. These application areas require a congestion-free mobility-supported MAC protocol to guarantee reliable data delivery. BN-MAC was evaluated using network simulator-2 (ns2) and compared with other hybrid MAC protocols, such as Zebra medium access control (Z-MAC), advertisement-based MAC (A-MAC), Speck-MAC, adaptive duty cycle SMAC (ADC-SMAC), and low-power real-time medium access control (LPR-MAC). The simulation results indicate that BN-MAC is a robust and energy-efficient protocol that outperforms other hybrid MAC protocols in the context of quality of service (QoS) parameters, such as energy consumption, latency, throughput, channel access time, successful delivery rate, coverage efficiency, and average duty cycle.https://doi.org/10.3390/s14030507

A Survey on Semantic Communications for Intelligent Wireless Networks

With deployment of 6G technology, it is envisioned that competitive edge of wireless networks will be sustained and next decade's communication requirements will be stratified. Also 6G will aim to aid development of a human society which is ubiquitous and mobile, simultaneously providing solutions to key challenges such as, coverage, capacity, etc. In addition, 6G will focus on providing intelligent use-cases and applications using higher data-rates over mill-meter waves and Tera-Hertz frequency. However, at higher frequencies multiple non-desired phenomena such as atmospheric absorption, blocking, etc., occur which create a bottleneck owing to resource (spectrum and energy) scarcity. Hence, following same trend of making efforts towards reproducing at receiver, exact information which was sent by transmitter, will result in a never ending need for higher bandwidth. A possible solution to such a challenge lies in semantic communications which focuses on meaning (context) of received data as opposed to only reproducing correct transmitted data. This in turn will require less bandwidth, and will reduce bottleneck due to various undesired phenomenon. In this respect, current article presents a detailed survey on recent technological trends in regard to semantic communications for intelligent wireless networks. We focus on semantic communications architecture including model, and source and channel coding. Next, we detail cross-layer interaction, and various goal-oriented communication applications. We also present overall semantic communications trends in detail, and identify challenges which need timely solutions before practical implementation of semantic communications within 6G wireless technology. Our survey article is an attempt to significantly contribute towards initiating future research directions in area of semantic communications for intelligent 6G wireless networks

Sistema de sensorização e controlo baseado em ZigBee para aplicação em bicicletas elétricas

Dissertação de mestrado integrado em Engenharia de ComunicaçõesEsta dissertação descreve uma solução para implementar a comunicação sem fios entre sensores indicadores de esforço físico, um smartphone e um sistema de controlo de uma bicicleta elétrica. Um dos objetivos deste trabalho consiste na especificação de alguns cenários para o controlo de esforço físico dos utilizadores, tirando partido do sistema de controlo dessa bicicleta, com a finalidade de proporcioná-los com a possibilidade de melhorar a sua aptidão física. Nesta dissertação é implementada uma infraestrutura de rede, baseada em ZigBee, para dar suporte à comunicação entre as diversas partes do sistema. Os testes efetuados visam aferir se a qualidade de serviço oferecida, mais especificamente no atraso fim a fim, é adequada para suportar os diversos cenários de controlo de esforço. O consumo de energia e o alcance também são considerados uma vez que são características fundamentais no contexto deste trabalho. A comunicação entre as diversas partes do sistema é assegurada através do módulo SDZ-539 da Spectec que desempenha o papel de gateway entre o smartphone e a rede ZigBee. A escolha deste módulo baseou-se no facto de permitir a comunicação entre sensores baseados em ZigBee/IEEE 802.15.4 com um smartphone Android. Durante a fase de implementação e testes verificou-se que este módulo tem algumas limitações, nomeadamente a necessidade de fazer polling, ao nível aplicacional, para receber os dados provenientes da rede ZigBee, e também pelo facto de ter um consumo de energia considerável mesmo em situações de baixa utilização. Com os resultados obtidos nos testes foi possível determinar o melhor compromisso entre o intervalo de polling, o atraso e o consumo energético de modo a responder às necessidades do sistema. Além disso foram obtidos resultados que mostram que o alcance das comunicações sem fios é aceitável tendo em conta o propósito para o qual o sistema foi projetado.This dissertation describes a solution for implementing the wireless communication between sensors that measure physical effort, a smartphone and an electric bicycle control system. One of the objectives of this work was to specify some scenarios to control users’ physical effort, by taking advantage of the bicycles control system, in order to provide them with the possibility of improving their fitness level. In this dissertation a network infrastructure, based on the ZigBee protocol, was implemented to support the communication between the different parts of the system. The tests performed aim to assess whether or not the quality of service, more specifically, the end to end delay, is adequate to support the different scenarios that were initially specified. The power consumption and range are also considered since they are key features in the context of this work. The communication between the different parts of the system is ensured by Spectec’s SDZ-539 module, which acts as a gateway between the smartphone and the ZigBee network. The choice of this module was due to the fact that it enabled the communication between ZigBee/IEEE 802.15.4 based sensors and an Android smartphone. During the implementation and testing phase it was verified that the module has some limitations, namely the need for polling at the Android application level to receive data from the ZigBee network, and also the fact that power consumption was considerably high even with low utilization. With the results obtained from the tests it was possible to determine a trade-off between the polling interval, the end to end delay and the power consumption in order to meet the systems requirements. Furthermore, the obtained results show that the wireless communication range is acceptable regarding the purpose for which the system was designed