Carlos Montez

Universidade Federal de Santa Catarina | UFSC · Departamento de Automação e Sistemas

Wireless Sensor Networks in large-area monitoring applications may be required to deal with emergency events, i.e., events from regions that suddenly require close attention. Nodes in these regions may demand increased data generation rates, and their communication with the base station (BS) should be prioritized. In this sense, a significant chall...

Most permissionless blockchains inherently suffer from throughput limitations. Layer-2 systems, such as side-chains or Rollups, have been proposed as a possible strategy to overcome this limitation. Layer-2 systems interact with the main-chain in two ways. First, users can move funds from/to the main-chain to/from the layer-2. Second, layer-2 syste...

Internet of Things (IoT) can be considered a suitable platform for industrial applications, enabling large systems that connect a huge number of intelligent sensors and subsequent data collection for analytical applications. This factor is responsible for the substantial increase in the current volume of data generated by IoT devices. The large vol...

The use of Wireless Sensor Networks in industrial environments imposes critical requirements such as low latency, high reliability, and robustness. To address these constraints, the IEEE 802.15 Task Group 4e developed the amendment IEEE 802.15.4e with three new MAC operation modes: TSCH, DSME, and LLDN. This paper aims to assess the feasibility of...

Uma das principais ameaças a uma rede veicular são os veículos maliciosos que geram mensagens falsas ou impróprias. As mensagens recebidas, tais como informações sobre acidentes, congestionamento, entre outras, precisam ser verificadas antes que uma ação seja tomada. Este trabalho propõe um sistema de reputação baseado em blockchain de consórcio e...

Automated and coordinated vehicle platoon driving is challenging as the complexity of vehicle control and the presence of unreliable wireless inter-vehicle communication. This subject has an interdisciplinary nature, involving control theories, vehicle dynamics, and communication. Due to the constant interaction between control logic and communicat...

Vehicular networks form an important pillar of current IntelligentTransportation Systems. Due to its specific characteristics, thesenetworks have been using reputation systems and or trust modelsto ensure security and trustworthiness. In addition, blockchainis a valuable technology that enables the development of thesesystems, addressing privacy, a...

This paper addresses the use of network coding algorithms combined with adequate retransmission techniques to improve the communication reliability of Wireless Sensor Networks (WSN). Basically, we assess the recently proposed Optimized Relay Selection Technique (ORST) operating together with four different retransmission techniques, three of them a...

A condução automatizada e coordenada de pelotões envolve teorias de controle, dinâmica dos veículos e comunicação veicular. Devido a uma constante interação entre a lógica de controle e a topologia de comunicação, uma abordagem de co-projeto para o controlador e o protocolo de comunicação torna-se necessária. Este artigo apresenta a AddP-CACC - uma...

A Internet das Coisas permite conectar objetos do mundo físico a Internet, possibilitando a criação de novas e inovadoras aplicações. Neste cenário, são apresentadas neste artigo, primeiramente, uma conceituação e uma proposta de arquitetura simplificada para aplicações de Internet das Coisas. Em seguida, são apontadas as principais tecnologias e p...

Milk-run tours with time windows are an essential strategy to collect goods to minimize production and transportation costs. Due to unexpected events at the supplier production or traffic congestion, delays can occur during the vehicle route execution, causing non-compliance between the logistics operator and the company. This paper describes the D...

is a remarkable network protocol to support the deployment of Low-Power Wide-Area Network applications for the Internet of Things. Its modulation scheme, , uses different transmission parameters to allow long-range bidirectional communication by trading-off range for time-on-air (ToA). The specification suggests using an Adaptive Data Rate (ADR) al...

Node mobility in multi-hop communication environments is an important feature of Wireless Sensor Network (WSN)-based monitoring systems. It allows nodes to have freedom of movement, without being restricted to a single-hop communication range. In IEEE 802.15.4 WSNs, nodes are only able to transfer data messages after completing a connection with a...

The development of flexible and efficient communication mechanisms is of paramount importance within the context of the Internet of Things (IoT) paradigm. IoT has been used for industrial, commercial, and residential applications, and the IEEE 802.15.4/ZigBee standard is one of the most suitable protocols for this purpose. This protocol is now freq...

The purpose of this paper is to present ongoing PhD work that investigates both the cooperative diversity and techniques of network coding needed to improve communication reliability in wireless sensor networks. In this context, we propose a relay selection technique. It aims to select the smallest number of relay nodes under certain constraints. O...

Energy limitation is one of the major bottlenecks during the operation of many emerging applications, such as electric vehicles, water and gas meters and a number of sensors used in the context of the Internet of Things and cyber‐physical systems. Energy harvesting techniques have arisen as a promising solution to minimize the energy issues found i...

As normas IEEE 802.15.4 e ZigBee definem a pilha de protocolos amplamente utilizada na operação de Redes de Sensores sem Fio (RSSF). A topologia cluster-tree, suportada por estas normas, oferece recursos como escalabilidade, sendo apontada pela literatura como a mais adequada para a implementação de aplicações de RSSFs em larga escala. Entretanto,...

The transmission and storage of data collected by the devices are essential components of the Internet of Things (IoT). When devices send unnecessary or redundant information, it spends more energy, unnecessarily using the communication channel, besides processing at the destination, data that make a small contribution to the application. Data comp...

Indoor Positioning Systems (IPS) constitutes a relevant research issue mainly due to the difficulties of employing Global Positioning System (GPS) technology in closed environments. Localization algorithms based on scene analysis technique, which map the environment signal levels at design time, present good results, being the main IEEE 802.11-base...

Cluster-tree topologies are commonly employed in large-scale Wireless Sensor Networks applications where nodes are randomly deployed. This topology presents several challenges related to connectivity and message schedulability. As a consequence, effective methods for network formation and operation are required. This work proposes a combination of...

Cooperative diversity techniques are being used to improve the communication reliability in Wireless Sensor Networks (WSN). Typically, these techniques use relay nodes to retransmit messages that otherwise would not be heard by their destination nodes. Thus, the relay selection techniques are fundamental to improve WSN’s communication behavior. How...

IEC 61850 is a standard for the design and operation of electrical Substation Automation Systems (SAS) that defines how data may be transferred among Intelligent Electronic Devices (IEDs). The defined data models can be mapped into application protocols, such as SV or GOOSE, which may run upon high speed Ethernet LANs bridged by IEEE 802.1Q complia...

Wireless Sensor Networks (WSN) are enabler technologies for the implementation of the Internet of Things (IoT) concept. WSNs provide an adequate infrastructure for the last-link communication with smart objects. Nevertheless, the wireless communication medium being inherently unreliable, there is the need to increase its communication reliability....

Wireless Sensor Networks (WSNs) can be used to support monitoring activities in a wide range of applications and communication environments. Its usage in extreme conditions, in what concerns pressure, temperature, and humidity, must be carefully assessed before the network deployment. In particular, the temperature variations have a direct impact u...

Wireless Body Area Networks (WBANs) must comply with stringent communication requirements. One of these requirements is reliable data delivery. However, it is well-know that wireless networks operating in the same frequency range and using overlapping channels, tend to experience interferences that may compromise the network Quality of Service. Thi...

The use of wireless sensor network nodes to support reliable communication exposes some challenging issues. For instance, the reduced available bandwidth combined with an error-prone communication medium impairs the provision of reliable communication services. Network coding techniques can be useful to mitigate some of these issues, where multiple...

The fields of precision agriculture, environmental engineering, among others, often have applications that use sensors to monitor the environment. Examples of such applications include pest control, irrigation process, soil fertility mapping, monitoring of forest areas and of urban rivers etc. Wireless sensor networks (WSNs) have been proposed as d...

Energy consumption is a major concern in Wireless Sensor Networks (WSNs) since nodes are powered by batteries. Usually, batteries have low capacity and can not be replaced due to economic and/or logistical issues. In addition, batteries are complex devices as they depend on electrochemical reactions to generate energy. As a result, batteries exhibi...

The operation of Wireless Sensor Networks (WSNs) is subject to multiple constraints, among which one of the most critical is available energy. Sensor nodes are typically powered by electrochemical batteries. The stored energy in battery devices is easily influenced by the operating temperature and the discharge current values. Therefore, it becomes...

In vehicular ad hoc networks (VANETs), cooperation between nodes is needed for proper performance of safety and traffic efficiency applications. A non-trivial scientific challenge in VANETs is the design of an adaptive broadcast protocol, which can provide efficient and end-to-end reliable warning messages dissemination. Usually, broadcast protocol...

The IEEE 802.15.4/ZigBee cluster-tree topology is a suitable technology to deploy wide-scale Wireless Sensor Networks (WSNs). These networks are usually designed to support convergecast traffic, where all communication paths go through the PAN (Personal Area Network) coordinator. Nevertheless, peer-to-peer communication relationships may be also re...

The IEEE 802.15.4/ZigBee set of standards is one of the most used wireless sensor network technologies. This set of standards supports cluster-tree networks, which are suitable topologies for wide-scale deployments. The design of wide-scale wireless sensor networks is a challenging task because it is difficult to test, analyse and validate new desi...

Energy consumption is a major issue in Wireless Sensor Networks (WSNs), as nodes are powered by chemical batteries with an upper bounded lifetime. Estimating the lifetime of batteries is a difficult task, as it depends on several factors, such as operating temperatures and discharge rates. Analytical battery models can be used for estimating both t...

The use of Wireless Sensor Network (WSN) technologies is an attractive option to support wide-scale monitoring applications, such as the ones that can be found in precision agriculture, environmental monitoring and industrial automation. The IEEE 802.15.4/ZigBee cluster-tree topology is a suitable topology to build wide-scale WSNs. Despite some of...

The IEEE 802.15.4/ZigBee standards support the implementation of cluster-tree networks, which are a suitable topology to deploy wide-scale networks. In this type of topology, an important issue is the configuration of the superframe duration that is allocated to each of the network clusters. In this paper, we propose an allocation scheme for settin...

The cooperative diversity is a widely used technique to improve the performance of communications in a Sensor Wireless Network (WSN). The relay selection is a decisive step in the application of this technique. This paper proposes a classification taxonomy of the approaches of relay selection and presents a study of literature, describing the used...

IEC 61850 is a communication standard for electrical Substation Automation Systems (SAS). It defines both the information model and services used for communication between Intelligent Electronic Devices (IEDs) in a substation. The adoption of this standard brings several advantages for the design and operation of substations. The abstract data mode...

The use of wireless sensor networks (WSN) to support critical monitoring applications is becoming a relevant topic of interest. These networks allow a highly flexible approach to data monitoring and, consequently, a major breakthrough for several application domains, from industrial control applications to large building domotics and health care ap...

Energy consumption is a major problem in Wireless Sensor Networks (WSNs) since in most scenarios nodes operate on batteries with reduced size and low capacity. Battery lifetime estimation is therefore crucial to evaluate the network behavior over time. In addition, battery lifetime estimation is a major challenge since it depends on many factors, s...

The next big change in the internet paradigm is called the internet of things, in which even the simplest device is connected to the internet. Wireless technologies are important assets in the diffusion of this concept, as they allow the easy and seamless connection of all devices. Wireless sensor networks (WSNs) are being established for sensing a...

In some Wireless Sensor Network applications the sensor nodes share the same sensing activity, which means that for a considerable number of applications, not all nodes are required to perform sensing tasks during the network lifetime. Sleep-scheduling approaches can be applied in this scenario, enabling that some nodes turn off their radios, savin...

The IEEE 802.11 standard has been evolving over the past decade, introducing a set of new mechanisms at the MAC layer to improve the Quality of Service (QoS) provided to the communication. Among such improvements, we highlight the evolution from earlier DCF and PCF, until more recent EDCA and HCCA MAC layer mechanisms. In this paper we perform a si...

Many Wireless Sensor Network (WSN) applications operate autonomously in unreliable or inaccessible environments, precluding maintenance or human intervention. Redundant deployment schemes are usually considered in this scenario, making the network resilient to failure and environmental changes. Furthermore, sleep-scheduling techniques can also be a...

The use of cooperative diversity techniques and network coding concepts are promising solutions to improve the communication reliability in industrial Wireless Sensor Networks (WSNs). In this paper, we propose the NetCoDer scheme to address this problem, whose design is based in these concepts. The effectiveness of the NetCoDer scheme is evaluated...

The purpose of this study is to find a self-organizing model for MWSN based on bee colonies in order to reduce the number of messages transmitted among nodes, and thus reduce the overall consumption energy while maintaining the efficiency of message delivery. The results obtained in this article are originated from simulations carried out with SINA...

Precision Spray is a technique to increase performance of Precision Agriculture. This spray technique may be aided by a Wireless Sensor Network, however, for such approach, the communication between the agricultural input applicator vehicle and network is critical due to its proper functioning. Thus, this work analyzes how the number of nodes in a...

The IEEE 802.15.4 standard proposes a flexible communication solution for Low-Rate Wireless Personal Area Networks, including Wireless Sensor Networks. In these net-works, the transmission of messages or the Guaranteed Time Slot allocation are coordinated by the traditional CSMA/CA scheme, which does not provide any additional traffic differentiati...

In this paper we propose a novel approach, named Real-Time Alternative-Route Definition (RT-ARounD), to support real-time message streams over large-scale wireless sensor networks. Starting from a standard cluster-tree topology, where each cluster has active and inactive periods, the proposal selects a set of nodes to build a mesh topology which is...

Resumo. As aplicaçaplicaç˜aplicações nasáreasnas´nasáreas de Agricultura de Precisão, Engenharia Am-biental, frequentemente, utilizam sensores para o monitoramento de ambien-tes, como por exemplo, no controle de pragas, no processo de irrigaçirrigaç˜irrigação, na determinaçdeterminaç˜determinação de mapas de solo e produtividade, no acompanhamento...

This paper proposes an approach for service differentiation in web servers that preserves the end-to-end mapping in conformance with PHB AF group. This novel approach uses dynamic scheduling techniques and selective discard of requests to achieve a proportional service differentiation. A prototype was built on Apache web server and experiments were...

The IEEE 802.15.4 standard provides a flexible communication support for low-rate wireless personal area networks) applications. When active, the beacon-enabled mode provides a real-time communication to the supported application by adopting a guaranteed time slot (GTS) mechanism. However, this mechanism permits only up to seven real-time communica...

In the design of Wireless Sensor Networks (WSN), lifetime estimation is an important issue. This benchmark is closely related to the energy consumption of nodes. However, this assessment is not a trivial task. In such context, we propose an innovative energy measurement system for WSN. The designed system was employed for energy consumption measure...

The Internet of Things is a new paradigm where smart embedded devices and systems are connected to the Internet. In this context, Wireless Sensor Networks (WSN) are becoming an important alternative for sensing and actuating critical applications like industrial automation, remote patient monitoring and domotics. The IEEE 802.15.4 protocol has been...

In several monitoring applications, such as those that can be found in industrial factory floor, it may be necessary to obtain an uniform sensing coverage, providing as much as possible the same coverage degree for the entire network area. The IEEE 802.15.4 has become an important standard in wireless sensor networks. However, the use of cluster-tr...

In some Wireless Sensor Network (WSN) applica-tions, it may be necessary to keep a large number of nodes sensing and transmitting data to a base station in order to have unbiased measurement values. Therefore, in addition to the traditional energy consumption issues, the spatial diversity of the monitored area is another relevant metric to evaluate...

An important feature for the design of algorithms for Wireless Sensor Networks is the estimation of its lifetime. To design communication protocols and data collection algorithms with low power consumption, a key factor is the ability to measure the actual consumption in the sensor node. This ability enables the verification of theoretical/simulate...

Resumo—Atualmente, o IEEE 802.15.4/ZigBeé e considerado uma das mais importantes tecnologias utilizadas em Redes de Sensores Sem Fio (RSSF). Nessas redes, as transmissões de mensagens ou aloca ao de GTS (Guaranteed Time Slot) são coordenadas por um mecanismo baseado em CSMA/CA, sem qualquer esquema adicional de diferencia ao de tráfego. Em um traba...

The main concern in Wireless Sensor Networks (WSN) algorithms and protocols are the energy consumption. Thus, the WSN lifetime is one of the most important metric used to measure the performance of the WSN approaches. Another important metric is the WSN spatial coverage, where the main goal is to obtain sensed data in a uniform way. This paper has...